ABSTRACT SPACINGS AND RATES OF ANHYDROUS AMMONIA ON FIVE GRASSES COMPARED TO AMMONIUM NITRATE FOR YIELD AND NITRATE-N CONTENT OF THE HERBAGE AND THE SOIL B)’ John Bertel Schou Objectives of this study were to compare the effects of anhydrous ammonia to ammonium nitrate, a standard nitro- gen source, on yields of herbage and on the accumulation of nitrate-N in the foliage and in the soil. Eight-month old stands of deep-rooted smooth bromegrass (Bromus inermis Leyss.), reed canarygrass (Phalaris arundinacea L.), tall fescue (Festuca arundinacea Schreb.), and orchardgrass (Dactylis glomerata L.) and shallow-rooted Kentucky blue- gress (Poa pratensis L.) were fertilized on a Conover loam soil in the spring of the first year with anhydrous ammonia injected 13-cm deep at rates of 112, 224, 448, and 896 kg N per hectare in 25-, 51-, 76-, and lOZ-cm rows, and with similar rates of N as ammonium nitrate broadcase in split applications. Total effects of the N treatments were evaluated by combining the yields of three cuts in the first year and three cuts in the second year. Nitrate-N in the foliage John Bertel Schou was determined in the first and second cuttings in both years. Nitrate—N in the soil was determined below a shallow— and a deep-rooted grass at increments of 15 cm to a depth of 152 cm in July and November of both years. Nitrate-N was determined by the specific ion electrode method. Yields of grasses were lower initially with anhy- drous ammonia than with ammonium nitrate but yields in the third cutting of the first year and in all cuttings in the second year favored anhydrous ammonia. Row spacing had no effect on total yield of the deepsrooted grasses but Kentucky bluegrass yielded less at the two widest row spacings at all but the lowest rate of nitrogen. At the end of the first year there was a 100% stimulation of all grasses between 25— and Slscm rows of anhydrous ammonia or with 896 kg N per hectare at all spacings. By the end of the second year, all grasses were stimulated 100% by 896 kg N per hectare as anhydrous ammonia spaced 102 cm apart. Grasses yielded in the order bromegrass > tall fescue > reed canary- grass > orchardgrass > bluegrass. Yields of the four deep- rooted grasses were 5, 12, 5, and 2 percent greater at rates of 112, 224, 448, and 896 kg N per hectare as anhy- drous ammonia, respectively, than with ammonium nitrate. Grasses increased in nitrate-N in the foliage with increased N. Orchardgrass had the highest levels of nitrate- N whereas tall fescue, reed canarygrass, and bromegrass had intermediate levels. Bluegrass had the lowest levels. John Bertel Schou Grasses fertilized with 112 kg N from both N sources were always below 0.15 percent nitrate-N (accepted "safe" for livestock). Second'year levels of nitrateeN were con- sidered safe. Accumulation of nitratevN in the soil was greater from anhydrous ammonia than from ammonium nitrate and, after three months, nitrate-N had leached to a depth of 30 to 45 cm. Deep«rooted bromegrass removed more total nitrate«N than shalIOerooted bluegrass. Nitrate-N from fertilizer N remained in the upper 76 cm of the soil pro- file in the first year with the exception of the 896-kg rate of N on bluegrass. At the 224vkg rate of N, higher grass yields with anhydrous ammonia than with ammonium nitrate in the first year were related to soil nitrate-N levels. With 448» and 896skg rates of N, nitrate—N in the soil was leached to greater depths the first year. Eigh- teen months after N application, nitrate-N was still accumulating in the surface 76 cm from anhydrous ammonia but not from ammonium nitrate. NitratevN from the higher rates of N with both sources was at or exceeded the depth of 122 cm, determined as the maximum root depth bf brome- grass. This nitrateeN could contribute to ground water contamination. SPACINGS AND RATES OF ANHYDROUS AMMONIA ON FIVE GRASSES COMPARED TO AMMONIUM NITRATE FOR YIELD AND NITRATE-N CONTENT OF THE HERBAGE AND THE SOIL B)’ John Bertel Schou A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Crop and Soil Science 1973 ACKNOWLEDGMENTS The author wishes to express sincere appreciation to Dr. M. B. Tesar for his assistance and encouragement in the research and for his constructive criticism in the pre- paration of this manuscript. Appreciation is also expressed to Drs.B. G. Ellis, J. B. Beard, R. E. Monroe, and P. G. Murphy for serving as guidance committee members. My days at Michigan State University (September 1970 to March 1973) went fast, but the many friendships and acquaintances made while there will not be forgotten. ii TABLE OF CONTENTS Page ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . ii LIST OF TABLES . . . . . . . . . . . . . . . . . . . v LIST OF FIGURES . . . . . . . . . . . . . . . . . . . vii INTRODUCTION . . . . . . . . . . . . . . . . . . . . 1 SECTION I. PRODUCTION . . . . . . . . . . . . . . . 3 A. Literature Review . . . . . . . . . . . . . . 3 B. Materials and Methods . . . . . . . . . . . . 6 C. Results and Discussion . . . . . . . . . . . 11 First Year (1971) . . . . . . . . . . . . . . 11 Second Year (1972) . . . . . . . . . . . . . 27 SECTION II. PLANT NITRATES . . . . . . . . . . . . . 44 A. Literature Review . . . . . . . . . . . . . . 44 B. Materials and Methods . . . . . . . . . . . . 46 C. Results and Discussion . . . . . . . . . . . 49 First Year (1971) . . . . . . . . . . . . . . 49 Second Year (1972) . . . . . . . . . . . . . 55 SECTION III. SOIL NITRATES . . . . . . . . . . . . . 60 A. Literature Review . . . . . . . . . . . . . . 60 B. Materials and Methods . . . . . . . . . . . . 63 C. Results and Discussion . . . . . . . . . . . 66 First Year (1971) . . . . . . . . . . . . . . 66 Second Year (1972) . . . . . . . . . . . . . 74 iii SUMMARY AND CONCLUSIONS . I. Production II. Plant Nitrates III. Soil Nitrates LITERATURE CITED APPENDIX iv Page 77 77 79 80 83 89 Table LIST OF TABLES Average monthly precipitation, air and soil temperature, and irrigation during the first (1971) and second (1972) growing season at East Lansing, Michigan . . . . First‘year forage yield in 1971 in mt/ha of five grasses fertilized on April 29, 1971, with AA and with AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971 . . . . . . . . . . . . . . Width of burn damage on grass foliage on May 23,1971, over rows of AA applied on April 29,1971 . . . . . . . . . Injury on orchardgrass on May 9-12, 1972, in percent of the stand of grass . . . . . Second-year forage yield in 1972 in mt/ha of five grasses fertilized on April 29, 1971, with AA and with AN in split applications on May 7 and 26, June 16, and July 9 and 14, 1971 . . . . . . . . . . Two-year total of forage yield in 7 mt/ha of five grasses in 1971 and 1972 when fertilized on April 29, 1971, with AA and with AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971 . Seasonal percentage yield distri- bution of five grasses Maturity and height of grasses . . . . . . . Effect of N source on percent nitrate-N of five grasses in 1971. (Dry weight basis) Effect of N source on percent nitrate- N of five grasses in 1972. (Dry weight basis) . . Page 10 12 21 28 29 35 42 48 50 Table Appendix 1. Average stimulation of grasses by N, in per- centage, rated visually at each harvest in two years by color and height of grasses between four row spacings of AA applied at four rates of N on April 29, 1971 . . . . . . . . . . . . Average stimulation of grasses by N, in per- centage, rated visually October 20, 1971, by color and height of grass between four row spacings of AA applied at four rates of N on April 29, 1971 . . . . . . . . Amounts of nitrate-N in kg/ha, determined under 76—cm rows of AA and under AN broad- cast on a Conover loam at East Lansing, Michigan. Fertilizer N as AA was applied 13-cm deep on April 29, 1971, and AN was applied in split applications on May 7 and 26, June 16, July 9 and 14, 1971 . Amounts of nitrate-N in kg/ha, determined under a point midway between 76-cm rows of AA applied 13-cm deep on April 29, 1971, on a Conover loam at East Lansing, Michigan . . . . vi Page 89 91 93 97 LIST OF FIGURES Figure Page 1. 2. Anhydrous ammonia applicator with three verti— cal knives O O O O O O O O O I O O O Q C O O O I 8 Vertical knife designed for anhydrous ammonia application to grass. The horizontal curved plate, designed by C. M. Hansen, Department of Agricultural Engineering, was welded to the commercial vertical knife to keep NH3 loss to a minimum . . . . . . . . . . . . . . . . . . . 9 Two-year total of forage yield in mt/ha of five grasses in 1971 and 1972 by individual cuts. Grasses were fertilized on April 29, 1971, with AA in four row spacings and with AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971 . . . . . . . . . . . . . . . . . . 15 Average width of burn damage on foliage of bromegrass, orchardgrass, reed canarygrass, tall fescue, and bluegrass over AA rows on May 23, 1971, from AA applied at four row spacings on April 29, 1971 . . . . . . . . . . . 20 Burn damage on grass foliage May 10, 1971, over rows of AA applied on April 29, 1971. In the foreground is orchardgrass fertilized with 896 kg N/ha in 76-cm rows . . . . . . . . . . . . . 22 Orchardgrass on October 20, 1971, that has recovered from the burn damage of AA applied on April 29, 1971, at 896 kg N/ha in 76-cm rows . . . . . . . . . . . . . . . . . . . . . . 22 Average stimulation of grass by N, in percen- tage, rated visually at each harvest in 1971 by color and height of grasses between four row spacings of AA applied at four rates of N on April 29, 1971 . . . . . . . . . . . . . . . . . 24 vii Figure 8. 10. 11. 12. 13. 14. 15. Kentucky bluegrass on October 20, 1971, ferti- lized on April 29, 1971, with 224 kg N/ha as AA in 102-cm spacings (white stakes). Stimula- tion of shallow-rooted KB was 65% of the grass between the stakes . . . . . . . . . . . . . . . Smooth bromegrass on October 20, 1971, ferti- lized on April 29, 1971, with 224 kg N/ha as AA in 102-cm spacings (white stakes). Stimulation of deep-rooted SB was 100% of the grass between the stakes . . . . . . . . . . . . . . . . . . Orchardgrass on May 25, 1972, fertilized on April 29, 1971, with AA in 102-cm rows. The grass has used all the N at the 112-kg rate, but not all the N at the 224-kg rate . . . . . . Tall fescue on July 9, 1972, fertilized on April 29, 1971, with AA in 76-cm rows. The grass has used all the N from AA at the 224- kg rate, but not all the N at the 448-kg rate . Average stimulation of grass by N, in percen- tage, rated visually at each harvest in 1972 by color and height of grasses between four row spacings of AA applied at four rates of N on April 29, 1971 . . . . . . . . . . . . . . . . . Two-year yields of grasses fertilized on April 29, 1971, with AA (average of 25-, 51-, 76-, and 102-cm row spacings) and with AN in split applications from May 7 to July 14, 1971 . . . . . . . . . . . . . . . . . . . . . . First-and second-year forage yields of shallow- and deep-rooted grasses fertilized on April 29, 1971, with AA (average of 25-, 51-, 76-, and 102-cm row spacings) and with AN in split appli- cations May 7 to July 14, 1971 . . . . . . . . . Nitrate-N content of orchardgrass, smooth brome- grass, Kentucky bluegrass, reed canarygrass, and tall fescue fertilized with AA on April 29, 1971, and with AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971. Nitrate- N content is an average of 25- and 76'cm AA row spacings. The 0.15% level is indicated as being potentially dangerous to livestock (sampled 5 cm away from the point of AA application) . . viii Page 26 26 31 31 33 38 39 53 Figure Page 16. 17. 18a. 18b. 19a. 19b. Hydraulic soil-coring machine with a quick release bit on the end of a 11 x 152 cm soil tube . . . . . . . . . . . . . . . . . . . . . . 65 Typical soil profile shown with 9wand ll-cm diameter soil tubes and a measuring trough used to divide the profile into 15-cm increments . . . . . . . . . . . . . . . . . . . 65 Nitrate-N at lS-cm increments in Conover loam profiles measured in 1971 and 1972 under smooth bromegrass fertilized with N as AA on April 29, 1971 . . . . . . . . . . . . . . . . . 67 Nitrate-N at 15-cm increments in Conover loam profiles measured in 1971 and 1972 under Kentucky bluegrass fertilized with N as AA on April 29, 1971 . . . . . . . . . . . . . . . . . 68 Nitrate-N at lS-cm increments in Conover loam profiles measured in 1971 and 1972 under smooth bromegrass fertilized with N as AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971 . . . . . . . . . . . . . . 69 Nitrate-N at lS-cm increments in Conover loam profiles measured in 1971 and 1972 under Kentucky bluegrass fertilized with N as AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971 . . . . . . . . . . . . . . 70 ix INTRODUCTION Our economically-conscious and ecologically-oriented society strives for increased efficiency in agricultural production while protecting the environment. Economical grass production depends on an economical source of nitrogen. Ideally, the source of N should not contaminate ground water with nitrate. Nitrate stimulates the growth of algae in lakes, rivers, and streams. If nitrate contami- nates well water, it may pose a hazard to human health (Smith, 1970). Per unit of N, anhydrous ammonia is the most eco- nomical source of N. In 1970, the price of N as anhydrous ammonia was about one-half the cost of N as ammonium nitrate. Furthermore, the N from anhydrous ammonia is not readily leached from the zone of injection because it is in the positively-charged ammonium form which is bound by negatively-charged soil particles. Nitrification of ammo- nium to nitrate-N proceeds only when the pH decreases to a tolerable level for nitrifying bacteria to live. There is a lack of information on yields of cool- season grasses fertilized with anhydrous ammonia in the United States. The lack of proper application equipment and the technology of application has hindered widespread use of anhydrous ammonia on grassland. Nitrate concentration in grass foliage is important because ruminant animals reduce the nitrate from the grass to the highly toxic nitrite compound. Again, little infor- mation is available on the effect of anhydrous ammonia on the nitrate content of the grass. The removal of soil nitrate by grass would prevent nitrate pollution of ground water. No data are available in the literature indicating the movement of soil nitrate from anhydrous ammonia to depths below grass roots. This investigation is divided into three sections as follows: 1. Production of grass II. Nitrate accumulation in the foliage III. Nitrate accumulation in the soil. SECTION I PRODUCTION A. Literature Review Large acreages of Northeastern and Northcentral United States grass pastures show a marked need for nitrogen (N). Today probably less than 5% of 50 million acres (xf this grassland is fertilized, partly because of the high cost per unit of N. Ammonium nitrate (AN) at $0.20/kg of N (USDA, 1970) gives only a marginal return in forage yield. Fertilization of temperate region grasses has increased dry matter forage yields at least 2.2 mt/ha with 112 kg N/ha (Lucey, 1959, Kennedy, 1960, Ramage, g£_al., 1958, Wagner, 1954, Washko and Marriott, 1960, Mitchell, 1967, and Tesar, Hansen, and Robertson, 1972). A more economical N source than AN per unit of N is anhydrous ammonia (AA) which costs $0.10/kg of N (USDA, 1970). However, application costs for AA are greater than AN, and the technology for application of AA is meager. Most of the limited work showing the effects of AA on grass has been done in the southern states on warm— season southern grasses. The first reported work was conducted in Mississippi by Andrews, Neely, and Edwards (1951) and Andrews (1956). Andrews, g£_al. (1951) reported higher yields of warm-season grasses in Mississippi with AA than with AN, and they stressed the value of AA as an economical source of N. Andrews (1956) reviewed studies where oats (Avena sativa L.), and a tall fescue (Festuca arundinacea Schreb.) and hop clover (Trifolium dubium L.) stand produced greater forage yields with AA than with AN. Nitrogen in 46-cm spacings gave greater total yields than at 69- or 91-cm spacings, but yields in the third cutting were the same for all spacings at 112 kg N/ha. The higher total yield of the fescue-clover stand with AA than AN was attributed to nitrification and later leaching of AN from the topsoil while a pH 4.9 retarded nitrification of AA in the root zone. Dallis grass (Paspalum dilatatum Poir.) in Mississippi in a dry year also produced higher forage yields with 111 kg N/ha of AA in 41-cm spacings than with AA in 82-cm spacings or with AN broadcast (Andrews, 1956). Bermudagrass (Cynodon dactylon L.), another warm- season grass, has been effectively fertilized with AA in the southern United States. Burton and Jackson (1962) in Georgia reported AA applied in 4l-cm rows was 94% as effec- tive as AN in increasing forage yields. Grass fertilizedwdth AA consistently produced highest yields in the second and third cuts when compared with AN cu‘ ammonium sulfate. Hill and Tucker (1968) in Oklahoma confirmed the higher yields with AN on bermudagrass in early cuttings and the higher yields in later cuttings with AA. With 40-cm injec- tion spacings on a silt loam soil, grass yields were simi- 1ar at rates of 112, 165, and 220 kg N/ha of AA in the first cut, apparently because the lowest rate supplied adequate N. They attributed the lack of total yield increase from the high rate of AA at 30- and 40-cm spac- ings to sod burn and poor retention of NHS' European research with AA on grass has been pri— marily on ryegrass (Lolium perenne L.), a short-rooted, drought-susceptible, cool-season grass. Burg, Brakel, and Schepers (1967a) in the Netherlands reported ammonium nitrate limestone (23% N) gave higher yields than AA in a dry year. Optimum dry matter forage yield was at 25 cm. At 40-cm spacings, a lO—cm N deficient area was evident between injections. Diffusion of NH3 was 10 cm on either side of the injections. Burg, Brakel, and Schepers (1967b) observed that root injury from AA injection accounted for yield decreases. Jeater (1967) in England reported that under sandy conditions, split AA treatments yielded more than single applications, but both AA treat- ments were inferior to AN. No indication of the amounts of NH3 loss or root injury was reported. Cowling (1968) found that individual AA injections 10-cm deep on 1—m square plots produced less forage than AN under dry con- ditions. The grass yields from AA were good in the first cutting, but did not provide a continuing supply of N. Split applications of AN totaling 400 kg N/ha gave much greater yields than a single application on a sandy clay loam. Drysdale (1970), however, reported a greater yield of timothy (Phleum pratense L.) with AA than with an equivalent N rate with AN. When AN was applied in split applications, timothy fertilized with AN yielded more. Tesar, Hansen, and Robertson (1971, 1972) in Michi- gan compared AA applicator knives on a mixture of cool- season pasture stands. They noted greater losses of NH3 with a rolling coulter-knife applicator than with a verti- cal knife. First-year yields favored AN. Total yields of first- and second-year yields from fertilization in the first year were similar with AN and AA. Yields from spacings of AA at 25, 51 and 76 cm were equal. The objective of this study was to determine the responses and yieldscfiffour deep-rooted grasses and one shallow—rooted grass when fertilized with broadcast AN at four rates of N and at similar rates of AA applied in four row spacings. B. Materials and Methods A Conover loam soil on the Michigan State University research farm at East Lansing, Michigan, was used for this two-year study. The area was limed to pH 6.5 and 227 kg/ha of 0-20-20 was disked into the soil. The perennials 'Lincoln' smooth bromegrass (SB) (Bromus inermis Leyss), 'commercial' reed canarygrass (RC) (Phalaris arundinacea L.), 'Penmead' orchardgrass (OG) (Dactylis glomerata L.), 'Kentucky 31' tall fescue (TF) (Festuca arundinacea Schreb), and 'common' Kentucky bluegrass (KB) (Poa pratensis L.) were sown August 14, 1970, at 11, 45, 34, 34,and 45 kg/ha, respectively. Excellent stands of grasses were established. Broadleaf weeds were controlled with 1/2 kg/ha 2,4-D amine applied October 8, 1970. A split-plot design with the large block being grass species was used in four replications. A plot size of 1.9 x 9.1 m for each fertilizer treatment was used. This permitted a minimum border of 36 cm between the closest treatments. Anhydrous ammonia was injected to a depth of 13 cm April 29, 1971, with an applicator attached to a tractor (Figure l). The vertical knives attached to the experimental applicator are shown in Figure 2. Design of the anhydrous ammonia sod knife was described by Hansen, Tesar, and Robertson (1970). The soil temperature was 10 C and the soil moisture content was 12%. Desired application rates were determined by calibration and trial runs. Rates of N were varied by regulating tractor speed. There was a minimum loss of NH30 Treatments of 112, 224, 448, and 896 kg N/ha were applied with injection knives spaced 25, 51, 76, and 102 cm for each rate, making a total of 16 treat- ments of AA. The following number of rows of NH3 were Figure 1. Anhydrous ammonia applicator with three verti- cal knives. attained for the four spacings of AA by making one or two trips with the applicator equipped with two or three knives: 25 cm--6 rows; 51 cm -4 rows ; 76 cm -3 rows; and 102 cm -2 rows. Similar rates of N as AN were applied broadcast in one application or split as follows: 112 kg N/ha - all on May 7 224 kg N/ha - all on May 7 448 kg N/ha - 224 on May 7; 112 on May 26; 112 on June 16 896 kg N/ha - 224 on May 7; 112 on May 26; 112 on June 16; 224 on July 9; 224 on July 14. The AN was applied in split applications at the two higher rates to minimize possible fertilizer injury. The AN was HANSEN ”g- Figure 2. Vertical knife designed for anhydrous ammonia application to grass. The horizontal curved plate, designed by C. M. Hansen, Department of Agricultural Engineering, was welded to the commercial vertical knife to keep NH to a minimum. 3 1055 applied with a 1.67-m fertilizer spreader calibrated to deliver desired rates by accurate regulation of the speed of the tractor used to tow the spreader. In calibration runs, the AN was collected in an attached tray. The average monthly precipitation, air and soil temperature, and irrigation for the growing season in 1971 and 1972 are shown in Table l. 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Cuttings of grass were made on June 11, July 28, and October 20, 1971, and on May 26, July 10, and October 19, 1972. A diagonal strip 0.9 x 8.2 m was harvested to a S—cm height from each plot to get representative fertili- zation of the AA applied in the four-row spacings. The center of the strip was 0.3 m to the left of the center at the beginning of the 8.2-m length and 0.3 m to the right of the center at the far end of the plot. A self- propelled harvestor was used. Borders were cut with a rotary mower and removed. Dry matter was determined from 1000-g samples of chopped forage dried with forced air for 24 hours at 54 C. Yields are expressed in metric tons per hectare (mt/ha) of forage containing 12% moisture. C. Results and Discussion First Year (1971) Smooth bromegrass was the highest yielding grass followed in order by reed canarygrass, tall fescue, orchard- grass, and Kentucky bluegrass (Table 2). At the two lowest rates of AN or AA, yields of bluegrass were significantly lower than the four deep-rooted grasses. At the two high- est rates of N, the yield differences between bluegrass and the four deep'rooted grasses were much smaller. 12 44.04 40.04 44.4 45.4 40.4 04.04 44.44 444 44.04 44.04 04.4 04.4 04.4 54.04 45.44 444 44.4 44.4 54.4 44.4 45.5 40.4 54.44 444 44 44.4 44.4 44.5 44.4 44.4 44.4 44.44 4>< 44.4 44.4 44.5 44.4 55.4 44.4 44.04 044 04.04 44.04 44.4 44.04 44.4 54.4 40.44 444 54.04 00.44 04.5 45.04 40.4 44.4 40.44 444 44.4 40.4 40.4 54.5 00.4 44.4 44.44 444 44 <4zozz< msommwzz< 44.0 44.0 +40.0 u 440044444 4 c4444: 40444 2 -- -- +44.0 n 0444 2 4 c44443 4044444 034 45.4 44.44 54.5 45.4 54.4 44.4 54.44 4>< 44.044 00.44 44.44 04.4 44.04 44.4 44.44 40.44 044 04.04 44.44 45.4 40.44 04.04 44.04 54.44 444 44.4 44.04 55.5 45.4 40.4 54.04 40.44 444 54.5 04.4 44.4 44.5 44.0 04.5 44.04 444 m4<444z 2342022< 44.4 04.4 .55.4 44.4 44.4 54.4 50.4 0 44< .oomwom 44 me mo 04 mm 4:544 . 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Q44 404 05 '14 The grasses did not react similarly in their yield response to the four rates of N applied as AA or AN. Grass yields increased as N as AA increased to 224 kg/ha but in- creased up to 448 kg N as AN. Yields of bromegrass, reed canarygrass, and bluegrass increased as N rates as AN in- creased from 448 to 896 kg/ha, while yields of orchardgrass and tall fescue decreased. Average yields of the deep- rooted grasses shown in Table 2 were higher in all cases than the shallow-rooted bluegrass. All grasses produced more forage in 1971 when fer- tilized with AA than with AN at 112 kg N/ha (Table 2). The average yield for all grasses with 112 kg N as AA was 8.31 mt/ha compared to 7.47 mt/ha for AN. This was a 11% advan- tage for AA. All of the five grasses fertilized with AA consis- tently produced lower yields in the first cutting than when fertilized with AN (Figure 3), but in the second and third cuttings the highest yields were usually obtained when AA was applied. This agrees with work on southern grasses by Andrews (1956), Burton and Jackson (1962), and Hill and Tucker (1968). At higher rates of AA, foliage injury was observed (Figure 4 and Table 3). The burned area is clearly shown in Figure 5 on several grasses two weeks after being fertilized with 896 kg N as AA in 76-cm rows. ‘Figure 6 shows how well orchardgrass at the high rate of N (shown in the foreground of Figure 5) had recovered from the burn FORAGE YIELD, Int/ha 22 20 16 14 12 10 N_o_N 112 kg N 224 kg N 448 kg N LSD os REED CANARYGRASS §n§ CUT 3 ~CUT 2 1972 Hum} CUT 1 E CUT 3 Q CUT 2 1971 E] CUT 1 15 aa a L“ WIN f - — == E '9‘: ‘ v vk...‘ '9'. O ‘9... 76 102 Check 102 25 51 AN AA AN AA AN AA AN AA FERTILIZER AND SPACING, cm Figure 3. Two-year total of forage yield in mt/ha of five grasses in 1971 and 1972 by individual cuts. Grasses were fertilized on April 29, 1971, with AA in four row spacings and with AN in split applications on May 7 and 26, June 16, July 9 and 14, 1971. FORAGE YIELD, Int/ha 26'_No~ lulu: LSD 22‘ .OS ECUT 3 CUT 2 1972 CUT 1 20— ECUT 3 18" ECUT 2 1971 IDCUTI 16 224 kg N 448 kg N SMOOTH BROMEG RASS 0.0. p" v ' 9:920 9’: r. 9’0 .435 C o 896k N III WIIII III III WIN! WWII Check Figure U} H \D N Ln H \O N In H \O N L!) K\ C) N Ln l\ O N In l\ .—4 r-G AN AA AN AA AN AA FERTILIZER AND SPACING, cm 3 (cont'd) N O H 25 51 76 102 Ii FORAGE YIELD, mt/ha Z O 2 U! U 0 U1 E E El Check AN Figure 3 (cont'd.) 25 51 112 kg N 76 102 17 224 kg N TALL FESCUE 25 51 76 102 448 kg N 25 51 76 102 896 k N 25 51 76 102 18 ORCHARDGRASS 224k N 112 kg N no N Esn.os 55:9 CUT 3 I- CUT 2 1972 b 1971 iii CUT 2 II n. II" I.-________________fl_.a~qmwwmwwm. III. a - - ”Illa—EE— E .. I=E====mewwmvkw a. .IIIII. ======_Viewfim €340. _=====_N.».~.~.~.§ I_==_===MMMMM»wM WEEquwwE$ WI E—E—E—g manomomgoufi WIIII________,_._._..ww.mwww.M WINE—=5:wwwwwwum ::: # 2: EE fig 12 10 8 ag\us .ogmo> mu<¢oa % IIIIIII IIIIII “ fl‘I ”fillgw‘k? . . . ====Wwwwuuwm Anchdnmc mnxwmmxwma 11111 v ”H Nod on ,Hm mN ==_wwm FERTILIZER AND SPACING, cm Figure 3 (cont 'd .) FORAGE YIELD, mt/ha 19 18 ~ No N 112 kg N 224 kg N 443 kg N 896 kg N 16 r LSD KENTUCKY BLUEGRASS / .05 ' -'-cur 3 --CUT 2 1972 12 _ [mm-CUT 1 E-cur 3 1o -- [Kg-CUT 2 1971 I: -CUT 1 .................. IIIIIII IIIIIIII IIII IIIIII 52522522552 IIIIIIII IIIII [III III II WI IIIIIII 25 51 76 102 25 51 76 102 51 76 102 5 02 E E AN AA AN AA AN AA FERTILIZER AND SPACING, cm Figure 3 (cont'd.) 17 F 16 - 15 b r-I H o H T l WIDTH OF BURN, cm 0 I Figure 4. 20 / ./ / / / / ‘/ 102-cm /' spacing / '/ [1’76-cm 1 l I .1 112 224 448 896 N, kg/ha Average width of burn damage on foliage of brome- grass, orchardgrass, reed canarygrass, tall fescue and bluegrass over AA rows on May 23, 1971, from AA applied at four row spacings on April 29, 1971. 21 Table 3. Width of burn damage on grass foliage on May 23, 1971, over rows of AA applied on April 29, 1971. W Avg Row N rate, Avg spacing kg/ha BG RC OG TF KB gg’ ¥g’ All 9 cm cm cm cm cm cm cm cm 25 112 O 0 0 2 0 l 0 224 0 2 2 2 0 2 l 448 0 3 2 4 S 3 3 896 5 10 8 8 9 8 8 Avg 1 4 3 4 4 4 3 51 112 0 0 2 2 2 1 l 224 3 2 2 4 2 3 3 448 3 3 3 9 S S 5 896 9 9 10 12 13 10 11 Avg 4 4 4 7 6 S 5 76 112 0 4 2 2 3 2 2 224 0 5 4 5 S 4 4 448 8 9 8 12 9 9 9 896 12 14 13 15 17 14 14 Avg 5 8 7 8 8 7 7 102 112 2 2 2 2 4 2 2 224 2 5 5 5 S 4 4 448 9 9 7 12 14 9 10 896 15 17 17 18 18 17 17 Avg 7 8 8 9 10 8 8 A11 112 1 2 2 2 2 2 2 spacings 224 1 4 3 4 3 3 3 448 S 6 S ,9 8 6 7 896 10 13 12 13 14 12 12 Avg 4 6 6 7 7 6 6 21 Figure 5. Burn damage on grass foliage May 10, 1971, over rows of AA applied on April 29, 1971. In the foreground is orchardgrass fertilized with 896 kg N/ha in 76—cm rows. )RCHRRD GRQSS I 7 1, I Figure 6. By October 20, 1971, orchardgrass had recovered from the burn damage of AA applied on April 29, 1971, at 896 kg N/ha in 76-cm rows. 23 injury six months after AA application. The grass burn from high rates of N in the wide spacings of AA and the readily available form of N in AN account for the greater yields from AN in the first cutting. Table 3 shows blue- grass and tall fescue were injured more than reed canary- grass and orchardgrass, while bromegrass was least injured. This burn damage was estimated one month after AA applica- tion and did not result from discoloration at the time of AA injection. Areas of light-green grass discoloration, caused by NH3 vapors, were observed when AA knives were removed from the sod at the end of the plots. Second-cutting yields of all grasses (Figure 3) were highest at the 25- and Sl-cm spacings at 112 and 224 kg N/ha of AA. However, yields were higher on blue- grass and tall fescue with AN than with AA in 76- and 102-cm spacings at 448 and 896 kg N. This reduction in yield with AA was attributed to burn damage being greatest on tall fescue and bluegrass. Second -cutting yields of all grasses (Figures 3 and 7) were highest at the 25- and Sl-cm spacings at 112 and 224 kg N/ha of AA. However, yields were higher on bluegrass and tall fescue with AN than with AA in 76- and 102-cm spacings at 448 and 896 kg N. This reduction in yield with AA may be attributed to burn damage being greatest on tall fescue and bluegrass. 24 .Han .mm HHHQ< :o 2 mo moump poem pm wowammw << mo mmcfiommm.zou know amozuoa mommmpm mo unmwon use hoHou kn Han :H umo>um£ (some um >HHm5mw> copay «omwucoohom :H .2 An mmmuw mo coaumHDEHum ommuo>< .u ohzwwm m;\wx .z ma\wx .z wax wee «mm NHH om wee «mm NHH a I u u a w. as . .ov . lam \\ d . AonOOHs cosy neopoop onHmnmv \ me .00 .um .mm w>< Joo Huma ‘DNIDVdS NHHMLHH NOIIVTHWILS % Eoém .\ . \\ .\.\ 9:23... 5-2 lllllll|.\\m.fiua% 8-3 cocoa-ooooooooooooooooooocoooocoot lg .I‘ilaclnd‘...coco-o...cocoon-cocooooooo OOH \. 25 In the third cutting (Figure 3),yields were higher from AA than AN in all grasses. The deep-rooted grasses in the third cutting increased in yields as the fertilizer rate increased to the 896-kg rate. Row spacings of AA at any N level had no effect on yield, except for bluegrass. Bluegrass in the third cut had greater yields with 112 kg N in wider spacings than in narrower spacings. Grasses fertilized with AA at 76- and 102-cm spacings with 448 and 896 kg N maintained a high yield in the third cutting because of the large amounts of N. Grass yields from AA in the first and second cut- tings were usually highest at 224 kg N/ha and similar at 112 and 448 kg N/ha of AA (Figure 3). This indicates that the grasses did not require more than the 224-kg rate of N for maximum yield in the first two cuttings. The trend for increased yields at higher rates of AA was established in the third cutting since some of the applied N was used in the first two cuttings and apparently N at rates above 224 kg/ha were necessary for maximum yields. In 1971 all spacings of AA were rated visually by color and height of grasses for stimulation of the grass between row spacings (Figure 7 and Appendix Table 1). All grasses were stimulated 100% in the ZS-cm rows of AA. As the row spacing increased beyond 25 cm, the percentage stimulation decreased for all grasses, especially for bluegrass, a shallow—rooted grass (Figure 8). As the rate Figure 8. Kentucky bluegrass on October 20, 1971, fertilized_ on April 29, 1971, with 224 kg N/ha as AA in 102- cm spacings (white stakes). Stimulation of shallow- rooted KB was 65% of the grass between the stakes. Figure 9. Smooth bromegrass on October 20, 1971, fertilized on April 29, 1971, with 224 kg N/ha as AA in 102- cm spacings (white stakes). Stimulation of deep- rooted SB was 100% of the grass between the stakes. 27 of N increased at each row spacing of AA, percent stimula- tion increased markedly. The bromegrass was typical of the deep-rooted grasses, and by the third cut in 1971 showed a 100% stimulation from N applied as AA (Figure 9 and Appendix Table 2). Percentage stimulation of grasses by N between 102-cm rows of AA at the 224-kg N rate on October 20, 1971, were 06 (84), SB (83), RC (76), TF (74), and KB (66) as shown in Appendix Table 2. Stimulation of the deep-rooted grasses fertilized with 224 kg N/ha in 76- and 102-cm rows was 14 and 13% higher, respectively, than the shallow- rooted bluegrass indicating that the deep-rooted grasses obtained N from a greater distance than Kentucky bluegrass. The four deep-rooted grasses had 100% of their area stimu- lated by N at the 448- and 896-kg/ha rates in 76-cm spacings and at the 896-kg rate in 102-cm rows. Even the short- rooted bluegrass‘wasstimulated on 100% of the area at the maximum spacing and maximum rate of N. Second Year (1972) In the second year, all grasses at all rates of AA yielded more than grasses with similar rates of AN (Table 5). Yields in 1972 were lower than in 1971. The grasses ranked in the order TF = SB > RC > DC > KB in 1972. The lower yields of orchardgrass were attributed to winter injury as evidenced by depressed yields in the first cutting in 1972 (Figure 3). Winter injury was found at high rates of N in the wider spacings (Table 4). 28 Table 4. Injury on orchardgrass on May 9-12, 1972, in percent of the stand of grass. N AN AA, injection spacings, cm Avg kg/ha 25 51 76 102 AA 112 3+ 0 0 4H 7 3 224 9+ 2 4H 10 11 7 448 3 11 11 40 23 21 896 25 31 42 41 34 37 Avg 10 11 14 24 19 + . . . . . No injury in three of four replications. ++ . . . - - No injury in two of four replications. High rates of N may have reduced carbohydrate reserves in the fall of 1971 and resulted in orchardgrass injury as suggested by Mitchell (1967) in Delaware, and by Reynolds (1969) in Tennessee. Orchardgrass fertilized with the two lowest rates of N, which did not cause serious injury to stands, had greater residual yields than reed canarygrass in 1972, except at the 102-cm spacing of AA. A dark green color of orchardgrass with 224 kg N as AA in 102-cm spac- ings in the first cutting in 1972 (Figure 10), showed this grass was still getting N from applied fertilizer. How- ever, at the 112-kg rate of N as AA (Figure 10) a lighter color of orchardgrass indicated the N had been used. By July of the second year the dark color of the deep-rooted 29 «5.5 mm.w oq.m 5m.w Nw.5 Nw.5 55.w wve mm.m < ow.o5 «v.55 em.w mm.NH wm.w o5.NH 5w.55 cow mN.5 m5.5 om.m mm.w mo.o ow.5 ww.w wee ow.v em.m mm.N 5o.m 5m.w wm.¢ m5.o «mm wm.m mo.v 5w.5 mw.v No.5 mo.m ow.e N55 mm zz< om.o mm.o +5o.o 5mmvmmm5w a :55553 moumw z -- -- +wo.o 05mg 2 m :5:553 mommmpw 035 mo.mm5 wm.m om.m O5.m 5m.o mm.5 om.m mo.o m>< mm.w Hm.m No.w Hm.05 No.5 mo.m wN.OH omw mo.o 50.0 ©5.m em.5 mm.m ew.m m5.w wee 55.m «H.v om.m 55.m mo.m 5N.m vm.e «mm 55.m oe.m ~5.5 wm.¢ om.m m¢.~ ow.m N55 m5< .mm m>< / mowoomm mmwpo .opmy z .wcHummw .5555 .55 van a 55:5 can .85 8:25 .05 can 5 5a: so m¢055a855dmm 555mm :5 z< 5553 use << :55: .5555 .55 5555< . co @65555550m mommmuw o>5w mo mn\ue :5 ~5m5 :5 @5055 owmpom 5mo5-wcooow .m o5nm5 30 .mommmhm ozp 5cm wafipmmEoo Mom o=Hm>+ Ho.5 wm.oH mm.5 om.m Nw.m mm.o mm.o mm.5 oe.HH 5w.w mw.m NN.e em.c mm.oa mw.5 wo.m ew.m 5w.o M5.0H om.5 mm.HH me.w mw.m mH.e mN.o 00.0 mo.w mo.NH ee.m mm.c em.e wm.5 me.HH mm.w Hm.m ma.e om.5 ma.HH wc.m mw.w Hw.m mm.m mm.m om.m Nw.w mo.o ew.m mm.~ 5H.m om.w mw.m 5m.m 5e.N mm.e eo.m 5N.w mm.NH mm.m em.o Hm.e mo.w OH.mH me.OH om.5 mm.m eH.w mm.HH we.m mN.o Nw.e He.w mm.HH +505 :55 mm.o 5m.w 5H.5 ow.m om.m mH.5 HN.NH om.w 55.e om.m o~.w 5m.NH om.m mo.o eo.e w>< omw wee eNN N55 HH< 5mmwmmm5w m can wnwummm a c5555: mopmh z away 2 m was mmovmmwuw a aflnuflz mwaflommm u opap z m use w250mmm a :5:553 mommmhw 035 5m.o mo.m eo.5 Hm.m me.m He.o em.m 5m.o mm.e mm.e oe.o cc.w eo.5 5N.~H 5o.m mm.m Hw.m OH.5 wo.NH ow.w mm.e Nw.~ 5w.o w5.HH Hm.m ~5.mH eo.OH mm.5 5m.m ow.5 0H.NH oo.w om.o mm.e mo.w 5m.NH m>< omw wee eNN NHH m>< omw wee eNN N55 w>< omw mo. mmq NOH 05 ’ .1, 1,,1 , 1,, , , i, 17,, , 1,7,-,*#111 Figure 10. Orchardgrass on May 25, 1972, fertilized on April 29, 1971, with AA in 102—cm rows. The grass has used all the N at the 112—kg rate, but not all the N at the 224-kg rate. Figure 11. Tall fescue on July 9, 1972, fertilized on April 29, 1971, with AA in 76-cm rows. The grass has used all the N from AA at the 224'kg rate, but not all the N at the 448-kg rate. 32 tall fescue indicated N was still available from the 448-kg rate as AA, but not from the 224—kg N rate (Figure 11). Average 1972 residual yields from AA (over all spacings) at 112, 224, 448 and 896 kg N/ha were 22, 41, 31 and 29% greater, respectively, than from AN (Table 5). Yields for most rates of N and most grasses were similar at the 25-, Sl-, and 76-cm spacings. Yields were greater, however, as the row spacings of AA increased. All five grasses had some residual effect from the 112 kg N applied in the previous year as AN, but the increase averaged only about 14% above the check. With AA, however, the increase ranged from 31% at the 25-cm spacing to 55% at the 102-cm spacing of AA. The relative increase was greater for bluegrass than for any of the deep-rooted grasses, with the greatest increase being at the widest spacing. The 1972 visual ratings by color and height of grasses on AA-fertilized plots as an indication of N stimulation is presented in Figure 12 and Appendix Table 1. The percentage of the grasses which were stimulated by N increased as N levels increased and as row spacings de- creased. Maximum stimulation of 100% was in 25-cm spacings at the maximum rate of 896 kg N/ha. Minimum stimulation of 30% for bluegrass and 35% of the four tall grasses was obtained at the lowest rate of N in the widest spacing. Deep-rooted grasses were stimulated more than bluegrass, the short-rooted grass. 33 .55m5 .mm 5559< :o 2 mo money 530m pm @ofiammm << mo mmzflommm 305 550m coozuon mommmww mo “swam: can noHOU 5n ~5m5 :5 umo>pmz come we 555w5m5> woven .owmunounom :5 .z.5n mmwpw mo cofiumasefium owmpo>< .NH owswwm 2:95 .z 2:35 .z oMm wee eNN N55 omw wee eNN N55 q q I Q I d n 1 on we \ 305005-305:ng 55505005155003 \ A. om \ ”55. .oo .um .mm 5:2. \ \ \ . % ‘DNIDVdS NaaMiaa Nouvmwiis \\ \x \\ \ \ \ ‘\ \\ .l \\ .\.\AHEU-H \ \ \ \.\ \ \ \\.\\ \\.\\ mcfiowmm 1 5555 L \\\ N555 .. 85 34 Yields in the second year continued to increase as rates of N increased from 112 to 896 kg, but the in- crease was larger with AA than AN, especially at the highest rate of N. This indicated the grasses were using more N from AA than from AN. In several replications of bluegrass a N deficiency as indicated by a light green grass color with 896 kg AN was seen by the third cutting in 1972. All bluegrass fertilized with 896 kg N as AA, however, had a dark green color by the third cutting in 1972. This indicated that not all N from AA had been used previously by the grass. Total Two Years Total effect of N was determined by combining 1971 and 1972 yields of the grasses fertilized only in 1971. The averages of the grass yields for the four deep-rooted grasses were similar for all four spacings of AA at each level of N (Table 6). It was surprising that the 102-cm spacing was as effective as the narrow spacings in its ef- fect on two'year total yields for the deep-rooted grasses. The short«rooted bluegrass, however, was significantly lower in yield in the 76‘ and 102-cm rows at all N levels except at the lowest rate of 112 kg/ha. This is seen in Figures 7, 8, and 12 which show that bluegrass was not stimu- lated to as great a distance from the AA row as the deep- rooted grasses in the wider row spacings. The AA applied 35 50.05 50.55 50.55 05.55 05.55 55.05 55.55 5>< 55.55 55.55 50.55 55.55 55.55 55.55 55.55 055 55.55 55.55 55.55 50.55 55.55 55.55 55.55 555 55.55 55.05 55.55 55.05 55.55 55.55 55.55 555 55.55 05.55 55.5 55.55 55.55 05.55 50.05 555 55 55.05 55.55 55.55 55.55 55.55 55.05 55.55 5>< 50.55 50.55 55.55 55.55 55.55 55.55 55.55 055 55.55 55.55 55.55 55.55 55.55 55.55 55.55 555 55.55 55.05 55.55 55.05 50.55 55.55 55.55 555 55.55 55.55 55.5 55.55 55.55 55.55 55.05 555 55 <5zozz< 550555:z< om.o 55.0 +50.0 55055505w 0 055553 50505 2 -- -1 5w.o n 0505 z m 05:55: 505505w 035 55 555 05 55 05.05 55.55 55.05 55.55 55.55 05.55 5>< 55.55 05.55 55.55 55.55 55.55 55.55 55.55 055 55.05 05.55 55.55 55.55 55.55 50.05 50.55 555 55.55 55.55 55.55 55.55 55.55 55.55 55.55 555 55.55 05.55 50.0 55.55 55.55 55.5 55.55 555 m5<555z 2552022< 55.5 50.5 55.5 05.5 55.5 55.5 55.55 5 a 55< .w% .mm 55 55 00 05 55 .55555 .5 505 w>< w>< 0050050 05050 0555 z 2500 w .5555 .55 0:5 5 55:5 .05 55:5 .05 055 5 552 so 5:555 -5555055 55555 :5 25 555: 5:5 << 555: .5555 .55 5555< no 0555555555 :55: 5555 000 5505 :5 505555w 0>5m mo wn\pa 05 05055 0w05om 50 50505 5505-035 .0 05055 36 .5055550 035 5:5 0:5550500 500 0:55>+ 00.05 00.0N 05.55 00.05 0H.NH 00.0 00.0 N0.0H 00.0w 00.55 05.05 00.05 00.05 00.HN 05.55 NH.0H 0N.~H 00.55 50.50 00.05 05.05 00.05 0N.0 50.0 00.55 00.NN 00.0H 00.05 05.05 00.55 50.00 00.05 0N.0H 00.0H 00.55 05.05 00.05 50.05 00.5 00.5H NN.0H 0m.NH 00.0 00.5 05.55 00.55 00.05 00.0 50.5 50.55 05.5N 00.05 00.05 0N.MH +555 HH.0H 00.00 50.05 N0.0H 05.05 00.55 00.50 00.0H 50.0H 00.05 00.05 00.05 50.05 00.05 00.55 00.05 50.50 00.55 00.05 00.55 50.00 50.00 55.00 50.05 50.05 0>< 000 000 0mm NHH HH< 550055550 5 0:5 0:50505 5 :50553 50555 2 0555 z 5 0:5 550055550 5 c5055: 50:50500 n 0555 z 5 0:5 0:50505 5 :50553 5055550 035 HN.0H 05.05 5H.55 50.05 H0.0H 00.05 00.05 05.05 55.05 00.05 00.05 00.50 00.55 00.05 55.55 00.05 05.5N 00.05 00.05 0H.HH 00.50 00.0N 00500 05.05 50.05 00.00 00.00 N5.H~ 05.05 00.05 0>< 000 000 000 055 0>< 000 000 0NN 055 00. n04 NOH 0n 37 in wider spacings requires fewer knives on the injection equipment to cover the same grass area. Fewer knives meant each knife was more efficient per unit land area. All grasses increased in yield as N increased to the 896‘kg N rate (Table 6). With AA, the grasses had a consistently higher yield than with AN. The increases, however, were small. For the four deepvrooted grasses, the increases favoring AA were 5, 12, 5, and 2% of the 112-, 224', 448-, and 896-kg rates of N, respectively (Figure 13). The 19% lower yield of bluegrass at the high rate of N as AN in contrast to AA was due largely to a considerably lower second-year yield with AN than with AA (Figure 14). Bluegrass was not getting the N from AN. late in the second year because most of the N was leached below its root zone (see Section III). The deep-rooted grasses, however, were getting the N from AN in the second year, even in the third cutting at the highest rate of N, as indicated by their high yields. Maximum root depths determined in the fall of the second year under a N rate of 224 kg/ha were as follows: tall fescue = 132 cm, > bromegrass = 122 cm, > reed canarygrass = 102 cm, > orchardgrass = 89 cm, > bluegrass = 76 cm. Grasses yielded in the order of bromegrass > tall fescue > reed canarygrass > orchardgrass > bluegrass, (Table 6). Bromegrass was higher yielding than the other deep-rooted grasses at the various spacings of N as AA and 38 22 r 1971 + 1972 20.. 18- 16 r A A «314— / J: \ 4.) E12 :3 ._J [-1-] H >‘10 A AVG. 4 DEEPvROOTED GRASSES C) KENTUCKY BLUEGRASS 0 l 1 1 I 112 224 448 896 N, kg/ha Figure 13. Two-year yields of grasses fertilized on April 29, 1971, with AA (average of 25-, Sl-, 76-, and 102-cm row spacings) and with AN in split applications May 7 to July 14, 1971. 12 71971 ’A______,____AAN A//’ A— II_A.AA o _________ —o AN ""”"’ AA 0 /o__ 0 YIELD, mt/ha YIELD, mt/ha 6 AVG. 4 DEEP-ROOTED GRASSES O KENTUCKY BLUEGRASS g R l J 0 l ' e A 112 224 448 896 N, kg/ha Figure 14. First- and second-year yields of shallow- and deep-rooted grasses fertilized on April 29, 1971, with AA (average of 25—, Sl-, 76-, and 102-cm row spacings) and with AN in split applications May 7 to July 14, 1971. 40 at varying rates of N with either source of N. The shallow- rooted bluegrass always had lowest yields. The four deep- rooted grasses yielded an average of 47% more than blue- grass. Winter injury to orchardgrass reduced yields in the second year at high N rates and contributed to lower two—year average yields than previous results in Michigan indicated (Tesar, 1972). Individual year comparisons in Figure 14 show grass yields were higher from AA than AN in 1971 and 1972 with 112 kg N, because more residual N was available for the grasses. In 1971 yields did not increase with AA at rates of N greater than 224 kg/ha, while AN continued to increase yields up to a rate of 448 kg of applied N. The grasses over the entire fertilized area used the readily avail- able nitrate from AN early in the first season. However, AA was concentrated in row spacings where it injured grass roots (when applied in high rates) but gradually became available to the grasses as nitrification proceeded and roots of grasses recovered. Grasses fertilized with AA had highest yields at all N rates and spacings in the third cut- ting in 1971 (Figure 3), and in all cuttings in 1972. In 1972, increased yields with AA and AA were almost linear for the deep-rooted grasses as rates increased from 112 to 896 kg N (Figure 14). Increases were greater with AA than AN, however, so that even though first-year yields at the two highest levels of AN were greater than with 41 AA, total two-year yields were somewhat greater with AA (Figure 13) as discussed earlier. In general, the four tall deep-rooted grasses reacted similarly to increases in N fertilizer and in- creases in row spacings with some minor exceptions such as those attributed to winter injury of orchardgrass (Table 5). Kentucky bluegrass reacted similarly to the two sources of fertilizer with the exception of a con- siderably lower yield from AN than from AA at the highest rate of N as indicated above. In every comparison, each grass at every rate of N produced a higher percentage of the first-year's yield in the first cutting when fertilized with AN than with AA, indicating more available N from the AN source, in the approximate S- to 6-week period after application (Table 7). 42 ‘ ‘Illll.ll |.| Ill! , ON wN om ON mN mm HN HN mm wN NN wm wN mm mm NH wN mm NH NH H5 Nu mN on an wN cm ow wN ow Nm mN hm wm Hm ow mN oN ow ow mH NN mm Hm w>< wN om ow mN wm Hw wH NH mo om om ow wm Nw wN NH mm mw ON ON wm Nu on on wm wN mm mm mm ow mN Hm um Nm um mm mN mN um mm mH mN mm HN cow NH MN co NH wN mm mH mH co HN 0N mm wN mm mm NH mN mo N mH mu Nu wN cm om NN mm mm Hm ow mN Hm om mm mm mm 0N mN mm om NH 0N om Hm www mH oN Ho NH oN mo oN mN um NN wH co mN NN ww 0H oN we w wH mm Nu HN Hw mm ON Hw mm wN mw mm wN mm mm 0N ww Hm mH ow ow wH mm mm Hm wNN NN mN mm ON mN mm om 0N ww wN HN mm mN NN ww NN mN om HH mH wn Nu oN mm nw ON mm nw HN wm mw wN mm mm mN ow mm wH mm ww NH ON we Hm NHH mh< m>< xx03ucox HHmH svnmaoho comm spoosm z .mommmpw o>Hm mo :oHuanNume wHon ommucoohom Hmcommom .N oHan 43 ON NM NN OM ON mM OH HM OH ON ON OM MM OM OM NM ON OM wN Nw Nm OM Ow NN OO ON Om OM Nm MM HN OM ON mM HN MM OH ON OH wN ON OM wM mM NM OM ON OM MN ow om NM OM OM Nw HM Om NM Om OM OH OM NN Nw OH Mw wH OM HN HM mN Hw NN OM MN OM NN Mw NN Nw NO ON Hm NH HO OH wO HN Nm NN ON OM OM ww NN Hw ON NM HN MM ON OM ON MM ON mM MN NM NN OM Ow mN mM MN mw wN NO ON NO ON ON OM OM ww ON Hw ON OM mN HM NM OM Mw mM Hw NM OM OM NN Mw mz< wM MN NN HN OM NN OM MN Ow ON OH ON ON HM MH ON HH mN OH OH OM Nw NM ww MM Ow wN Ow ON Ow mm NN Mw MN wm mN -mo NN Om MM MH OH ON mN MH HN OH OH wH wN ON OM ON NN ON HN OM OH OM MO Mm Om Ow OO Mm HN Nm HN Om NN HN NN HN NN HN NN HN NN HN O>< OOO Oww wNN NHH SECTION II PLANT NITRATES A. Literature Review Nitrogen (N) fertilization produces high grass yields, distributes the yield throughout the season, and increases the content of nitrate-N in the grass foliage as reported by George e£_al. (1972) in Indiana, Kennedy (1960) in New York, Look Kin and MacKenzie (1970) in Quebec, and Reynolds, Lewis, and Laaker (1971) in Tennes- see. Nitrate-N is an important chemical constituent to consider in forage quality because it is reduced by rumi- nant microorganisms to the toxic nitrite form which easily permeates intestinal walls and enters the blood (Wright and Davison, 1964). Lethal amounts of nitrite from nitrate in the rumen or stomach vary with species, age and physiological status of the animal, type of ration, and the amount of feed in the rumen at any one time. Sublethal concentrations in the 0.07 to 0.20% (700 to 2000 ppm) nitrate-N range have caused decreased milk production, abortion, and loss of weight as reported by Hill and Ackerson (1964) in Nebraska, Crawford, Kennedy, and Wright (1960) and Wright and 44 A . M.._ a.... 4S Davison (1964) in New York. Ryan, Wedin, and Bryan (1972) in Iowa considered 0.15% nitrate-N safe for four perennial grasses based on the report of Wright and Davison (1964). Smith (1967) in Missouri reported 0.11% nitratevN to be a safe concentration, while 0.40% nitrate-N in forage was considered potentially fatal to livestock. Wright and Davison (1964), Crawford, Kennedy, and Johnson (1961), and Crawford, e£_al. (1960) listed drought, low light conditions, growth inhibitors, and high soil N as contributing factors to high grass nitrate-N accumula- tion. They also emphasized species, part of the plant, nitrate reductase activity, and stage of maturity as im- portant internal factors that had an effect on nitrate-N concentrations in grass. Bluegrasses were considered non- accumulators of nitrate-N. Highest concentration of nitrate-N was usually in the stem, especially lower inter- nodes, with less nitrate-N in the leaves, and least nitrate-N in the floral parts. Mature grass, when accom- panied by a large dry matter increase, had a low level of nitrate-N. Nitrate-N accumulation has been reported for solid fertilizer applications on smooth bromegrass (Bromus inermis LeyssJ, Smith and Lund (1965), Look Kin and MacKenzie (1970), Murphy and Smith (1967), Ryan, g£_§l. (1972), Hill and Ackerson (1964), orchardgrass (Dactylis glgmerata L.), Dotzenko and Henderson (1964), Murphy and 46 Smith (1964), apGriffith and Johnston (1960), Ryan, et a1. (1972), and Reynolds, Lewis, and Laaker (1971), tall fes- cue (Festuca arundinacea Schreb), Murphy and Smith (1967), apGriffith and Johnston (1960), Ryan, et a1. (1972), George, et a1. (1972), and Hojjati, Taylor, and Templeton (1972), reed canarygrass (Phalaris arundinacea L.), Ryan, g£_al. (1972), and Kentucky bluegrass (Poa pratensis L.), Madison (1972). However, little information is available on accumulation of nitrate-N in perennial grasses fer- tilized with anhydrous ammonia. Lechtenberg, g£_gl. (1970) in Indiana reported anhydrous ammonia gave lower "high levels of nitrate" than similar N rates as ammonium nitrate. They noted no adverse effects on animal performance from nitrate-N levels as high as 0.30% in bromegrass and orchard- grass. The objective of this section of the study was to determine the effect of four rates and four row spacings of anhydrous ammonia on the accumulation of nitrate-N in five perennial grasses. B. Materials and Methods The establishment of stands of orchardgrass (OG), reed canarygrass (RC), smooth bromegrass (SB), tall fescue (TF), and Kentucky bluegrass (KB) and the application of anhydrous ammonia (AA and ammonium nitrate (AN) were described in Section I—B, Materials and methods. Average 47 monthly air and soil temperatures and precipitation and irrigation added were included in Section I-B. A combined leaf and stem sample from each grass was taken on June 10 and July 23, 1971, on four replica- tions, and on May 25 and July 21, 1972, on three replica- tions on the following: Check 112 kg N as AN and AA in 25- and 76-cm rows 224 kg N as AN and AA in 25- and 76-cm rows 448 kg N as AN and AA in 25- and 76-cm rows 896 kg N as AN and AA in 25-, 51-, 76-, and 102-cm rows. Samples were taken one or two days before forage harvests. The range of height and stage of maturity of each grass in the first harvest on May 23, 1971, and on May 25, 1972, are shown in Table 8. Grasses were similar in . maturity in 1971 and 1972, but varied in height. Height was greatly influenced by rates of nitrogen. Each foliage sample was composed of five sub-samples selected at random 5 cm on either side of AA rows within each plot of grass. On grasses fertilized with AN and on check plots, the samples were chosen at random within each 1.9 x 9.1 m plot. A composite sample was wrapped tightly in a cellophane bag and transported in dry ice to a freezer where the samples were kept at S C until analyzed. J- 48 OcHOmoA mH-m -poon ouwH OHPMH OcHOmoz mmmpmosHO Nxospmox OcHOmoO OcHOmo: Ow-mN -HOOO oumH ON-ON -poon opmH ozomow HHmN OGHOmoH ow-ON OcHOmo: ON-NN ‘uooO opmH mmmpmwpmgopo wO-MH poon NHHmm ON-ON poop NHHmm mmmHONHmcmo woom OcHOwoc wO-MN -poon opmH Hw-Om poop NHHmm mmmHOoEoHO apooEO So so . OHSMHO: mwNHm aflfiwfimm 0mmy.m NNQH .mN Na: HNmH .mN Na: moHoomm .mommmum mo pano: can NOHHSHOZ .O oHOmN 49 Nitrate-N was determined by the nitrate electrode method described by Paul and Carlson (1968) and modified by use of a saturated calcium sulfate solution (in place of an aluminum resin) to maintain a high pH and remove interfer- ing anions in the solution. A 10.0vg sample of frozen leaf and stem material was homogenized in 100 ml of a saturated calcium solution in a waring blendor set at full speed for one minute. Longer intervals of blending samples were found to only slightly improve analyses. The homogenized material was passed through cheesecloth before a determina- tion was made on a sample. Nitrate results are reported on a dry weight basis as nitrate-nitrogen (nitratevN). Field dry weight determinations from the forage cuts on the same plots were used because these determinations of dry matter were from 1000'g samples. C. Results and Discussion First Year (1971) The effect of AA and AN sources of nitrogen on the percentage of nitrate—N of five grasses in 1971 is shown in Table 9. All grasses increased in nitratevN from June to July with greatest increases with highest amounts of applied N. The average level of accumulation on June 10 and July 23 was in the order of 06 > TF = RC = SB > KB, although reed can- arygrass at high rates of N accumulated more nitratethjuuitall SO . I." I'll-I! oNN. mHH. ooH. Hmo. HON. mmH. HNN. NoH. Nmm. omo. mHN. HoH. on. NmN. m>< Nom. moH. NoH. moo. on. on. oom. NmH. mom. HwH. me. HmH. Noo. mmm. oom mom. NmH. NoH. wmo. Nwm. NoH. mom. NHH.. omm. ooo. oNN. NHH. NHm. HNm. mww wNH. omo. NNo. mmo. moH. on. omm. mmo. HwH. NNo. NmH. NNo. HmN. omH. wNN mNo. moo. mmo. NHo. omo. mNo. NoH. oNo. mmo. Nwo. moo. moo. moo. mHH. NHH mm zz< mmo. mwo. moo. moo. HmN\NO ++HoH. M8:3 ++ooo. u Hmoommopm o :Hoomz moon“ 2 -- -- -- -- HmN\NO ++oom. “HoH\oO ++ooH. u mom“ 2 o :Hoqu mommohm 03% oom. an. moo. ooo. Nmm. NmH. oNN. HoH. mmm. me. HmH. oHH. owm. Nwm. m>< mo.omo mmw. oo mmN. -- Nom. -- NNw. -- wom. -- NNm. -- omN. -- oom omm. omN. ooo. oNH. mom. omo. Now. on. NmN. mom. wHN. mmH. mmo. on. oww mHH. mwo. mmo. HHo. me. Hmo. moH. mmo. moH. mwo. wHH. owo. owH. mNo. wNN NNo. -- oHo. -- omo. -- mmo. -- Nmo. -- mmo. -- mmo. -- NHH me< om me.owmm>wm ON um om oo 2 Hmflmoo ucmHoa NHOO .HNOH :H mommmHO o>Hm mo z-oumHuHc +ucoupom co oopsom 2 mo uoowmm .O oHOmN 51 .oumv OGHHOEwm m :o mommmHO ozu Nam OcHHmOEoo mom osHm>++ .mcoHumoHHOoH anom+ OOM. NOM. OOO. ONO. MHN. NMM. mmN. NNH. NOO. HHN. OOM. NHN. ONH. NwH. wNO. wOO. NNO. MOO. OOO. ONH. MHH. ONO. OOO. NOO. mOO. OOO. OOO. mNO. NwH. MHN. wOH. NOH. wOH. OOO. HmO. OOH. NOH. OOH. MOO. OOO. ONO. OMO. ONO. OMO. OMO. MNO. HNO. ONO. mMO. ONO. OHO. wNO. MHw. NMw. NNO. OOO. OwN. ONM. MON. HON. ONH. NMN. HwM. OMN. MON. wOH. OOO. OOH. wNO. OOO. OHH. NmH. MMH. NOO. HOO. mOO. OOH. wOH. OOO. OOO. ONM. mOO. NMM. mmo. HMM. OwO. wOO. mNH. OOO NOH NOM. NOO. OOM. OOO. NON. OOO. HON. OOH. OOO Hm HmN\NO ++NHN. ”HoH\oO ++OOO. u Hmovmmmhm a cam OcHowOm m :HOOH3 moumh z Hm~\No ++NwH. ”HoH\oO ++NOO. u opmh z m Ocm mmoOmmeO m :Hnqu mOCHomOO HmN\NO ++moN. ”HoH\oO ++OOO. u mama z m Ono OcHomOm m :Hapwz momwmam 029 NMN. OOO. OHN. OOO. NwN. mOO. mOm. wHN. O>< mO OOH NOO. HHH. OOm. OHH. ONm. mHH. OwO. mON. OOO mmN. OOO. NNN. OOO. owm. OOO. HHw. NON. Oww OMN. ONO. OMH. OOO. OOH. OOO. mON. HOH. wNN ON Ocm me. mNO. NOH. me. NHH. HOO. NmH. mMH. NHH mN NmN. wOO. mON. ONO. NNN. OOO. mmM. NOH. O>< wMM. mOO. OOM. OOO. OHw. ONO. ONO. mON. OOO OMN. mOO. OON. HOO. wON. ONO. OOM. NHN. Oww OMN. OmO. NMH. wOO. OMH. OOO. OON. MOH. wNN OON. OOO. OHH. OOO. mmH. OOO. HOH. NmH. NHH ON 52 fescue. These levels of nitrate-N in AN fertilized grasses are similar to levels reported by Murphy and Smith (1967) in Missouri and Ryan, g£_gl. (1972) in Iowa. Levels of nitrate-N were relatively similar as row spacing of AA increased from 25 to 76 cm. Nitrate-N percentages were higher with AN than with AA six weeks after application in most instances. Twelve weeks after application, how- ever, nitrate'N levels were higher in all grasses with AA at lower rates of 112 and 224 kg N, nearly equal with both N sources at 448 kg N, but higher with AN at the 896-kg rate (Figure 15). Hazardous levels of nitrate-N for ruminant animals were reported to be 0.15% (1500 ppm) nitrate-N by Wright and Davidson (1964) in New York, and were considered potentially dangerous in this study. It must be con- sidered that the high percentage of nitratevN shown in Figure 15 was in grass sampled a 5-cm distance from AA rows. Grass midway between AA rows was getting less N. Therefore, a mixture of the low and high nitrate-N grasses at the time of forage cutting represented a "safety factor" because ruminant animals would probably not consume forage consisting only of high nitrate—N plants. Six weeks (June 10) after AA was applied, no dangerous levels of nitrate—N were found in bromegrass, reed canarygrass, and bluegrass (Table 9). Orchardgrass, however, had safe nitrate-N levels only with 25-cm AA 53 A.coHumoHHmOm << mo ucHom map Eogm Nmzm Eu m OoHQEMOO .Muoumo>HH ow machowcmw NHHmHucouom OGHOO ma OoumoHOcH wH Ho>OH NmH.O oON .mmcHummm 30H << Eo.ON Ocm -mN we owmpo>m cm mH ucoucoo z-oumhqu .HNoH .wH oeo o NHoo .OH mono .oN oco N No: :0 mcoHumoHHooa OHHOm :H z< OOH: Ocm .HNOH .ON HHHO< :0 << aqu OoNHHHuHow osumom HHmu ch .mmmHONHmnmu Oooy .mmmHOosHO quau:OM .mmmpOoEOHO :pooEm .mmmHOOHwnugo mo ucoucoo z-oumhqu .mH oHSOHm oo\mx .omHooaw z oom mow wNN NHH o oom mow wNm NHH o [lb ‘4 H H . H H. \\\““M\\ \\ \‘“\I\I\ lllll <<fl\\\ \\ . \\ mm< HwO. OmO. OOO. OMO. OmO. NNO. .OOO. wwH. MwO. OOH. NMO. OOO. NMO. wwO. OOO mHO. wMO. NOO. OOO. NHO. owO. OMO. OOO. OHO. mwO. OHO. wwO. MHO. HHO. Oww OHO. MHO. MHO. OOO. OOO. mHO. OOO. OHO. NHO. OHO. NOO. OHO. NHO. OOO. wNN NOO. NHO. mOO. OHO. OOO. OHO. OOO. OHO. OOO. ONO. NOO. OHO. NOO. MHO. NHH mN IZ< moo. mHo. moo. mmo. HHN\NO ++NHo. “Hmm\mO ++omo. u HmoOmmowm o cHOOHz meow“ z -- -- -- -- HHN\NO ++oHo. ”Hmm\mo ++Noo. n ooww z o sonomz mommopm ozN NHo. mmo. woo. NHo. mHo. mmo. mHo. Nwo. mHo. mmo. omo. omo. NHo. NNo. m>< mo omo ONO. NmO. NOO. NHO. wNO. OOO. mNO. OOO. NMO. OOO. OHO. MOO. NNO. OMO. OOO NHO. OHO. MOO. OHO. wHO. HNO. OHO. ONO. OHO. OHO. NHO. MNO. NOO. OHO. Oww OOO. OHO. wOO. wHO. OHO. OHO. OHO. NMO. MHO. mHO. OOO. wHO. OOO. OHO. wNN OOO. NHO. MOO. NHO. OHO. OHO. HHO. OHO. OOO. NNO. OOO. OHO. NHO. wHO. NHH mN . HH< < om .oo m>< me om om oo 2 fl.mHmmO HOOHoz NHOO .NNOH :H mommmwm o>Hm mo ZpoumeH: +uaooHoO :o oopnom 2 mo uoomwm .OH oHOmN 57 .oumv OcHHOEmm m :o mommmaw ozu Nam OcHummaoo How osHa> ++ .mcoHumoHHmon ooHcN+ HOO. MMO. NOO. OOO. OHO. MwO. MHO. OOO. NOO. ONO. OwO. wHO. OOO. NOO. NHH. OHH. MHO. NNO. HMO. owO. OwO. ONO. OHO. OwO. NOO. wOO. ONO. MHO. NMO. OHO. OOO. HHO. OOO. OOO. MOO. OOO. MHO. OOO. MOO. wOO. OOO. OHO. HNO. ONO. HNO. OHO. MHO. MNO. MNO. NMO. OMO. HHO. OOO. OMO. NOO. OHO. NNO. wMO. OHO. OOO. OOO. NNO. NMO. MHO. OOO. OOO. MNH. owH. MHO. OMO. MwO. NOO. OMO. ONO. OHO. wMO. NOH. NNO. MNO. OHO. OwH. OOO. MMO. OOO. MMO. NOO. OOO. wMO. OOO. OMO. OOO. OOO. NHH. NOH. NOO. MNH. OOO. OHO. OHO. MOO. HOH. OHH. OHO. MHO. OOH. NOO. ++mwo. ++wmo. ++Nwo. MNO. MOO. OHO. HHO. OOO. ONO. MOO. OHO. OOO. OOO. OHH. NNN. OOO. OMH. OOO. OHH. OOO NOH HMO. OOO. ONO. OOO. OOO HM HHN\NO ++Hmo. "Hmm\mO Hmovmmmhw m Ocm OcHomOm m :chHz mopmh z HHN\NO ++mHo. ”Hmm\mO away 2 m Ocm Hmovmmmhm m :ngHz mmcHomOO HHN\NO ++mmo. ”Hmm\mo u ouma z m Oam OcHomOm m :chHz mommmpw 03N MMO. NHH. NMO. OMO. ONO. NOO. MNH. OMO. wwO. OHO. wHO. ONO. HHO. OOO. OOO. MHO. MNO. HHO. OHO. OOO. wwO. MOO. MMO. ONO. OHO. OwO. ONO. MOO. wNO. OHO. OHO. OMO. HHO. OOO. NOO. wHO. wMO. OOO. OOO. OOO. NMO. wNO. ONO. HHO. MHO. wwO. MOH. NwO. NHO. NHO. O>< OOO Oww wNN NHH O>< OOO Oww wNN NHH MO OOH ON Ono MN ON 58 were all below the critical level except on May 25 in tall fescue and reed canarygrass with 896 kg N as AA in Sl-cm rows. These two determinations appear to be higher than expected compared with other AA spacings. Anhydrous ammonia contributed to higher nitrate-N levels in grass foliage than AN in the second year. This indicated that more N was available in the second year from AA than AN because of greater N carry-over. Grass samples taken May 25 from the low N treat- ments were similar to the checks (Table 10). Average level of nitrate-N accumulation was in the order of TF > RC > SB > OG > KB for both N sources. Orchardgrass nitrate-N levels were lower than tall fescue, reed canarygrass, and bromegrass levels at high N rates because of slow regrowth and winter injury. Slow regrowth was possibly caused by low levels of carbohydrates under N fertilization as reported by Mitchell (1967) and Reynolds (1969). High second.and third-cutting yields in 1971 from orchardgrass had probably removed much of the soil nitrate-N. The low level of nitrate-N in orchardgrass at low N rates was similar to bromegrass where soil nitrate-N was found to be very low. By July 21, 1972, levels of nitrate-N were less than 0.09% on all grass treatments except at the 896-kg N rate as AA in 102-cm spacings. At this maximum rate and widest spacing, all grasses had high nitrate-N levels, 59 but were still below the potentially hazardous level. Apparently, no danger from high nitrate-N levels can be attributed to residual N in the second season at N rates up to 448 kg. By July 21, bluegrass had nitrate-N levels below 0.01% with all N rates as AN and with low rates of AA (Table 10). At the 896-kg rate as AA in 51-, 76-, and 102-cm rows, nitrate-N levels of 0.04 to 0.11% had accumulated. The four deep-rooted grasses (Table 10) had higher nitrate-N accumulations than the shallow-rooted bluegrass with 896 kg N either as AN or as AA in 25-cm rows. A low percentage of nitrate-N in bluegrass indicated the applied N in the root zone (about 30 to 45 cm deep) had been utilized when fertilization was with AN. However, the high levels of nitrate-N in the foliage under 896 kg N as AA indicated N was still available to the bluegrass roots. This was indeed the case as will be discussed in the next section. Smooth bromegrass, however, had a high level of plant nitrate-N accumulation which was associated with a high level of soil nitrate-N accumulation. Smith and Sund (1965) in Wisconsin reported bromegrass contained large amounts of nitrate-N when the soil nitrate—N was high. In their study, bromegrass grown in association with alfalfa had plant nitrate-N as high as 1.36%. SECTION III SOIL NITRATES A. Literature Review With high rates of nitrogen (N) on grass there is concern for surface and ground water contamination from soil nitrate-N not used by the grass. No data are avail- able, however, indicating the movement of nitrate-N from anhydrous ammonia to depths below grass roots, while in- formation is available on nitrate-N movement from ammo- nium nitrate. Larson, Carter, and Vasey (1971) in North Dakota reported no nitrate-N movement below 15 to 61 cm with 298 kg N/ha as ammonium nitrate applied annually for 15 years on bromegrass (Bromus inermis Leyss). The high- est concentration 10 months after their fall application was at a soil depth of 30-46 cm. Power, e£_al. (1972) in North Dakota reported soil nitrate-N levels over four years were similar to the checks with a llO-kg rate of N. Furthermore, Ogus and Fox (1970) in Nebraska reported the deep bromegrass roots were more effective on a per unit weight basis for nitrate-N uptake than the shallow TOOtS . 60 61 Accumulations of nitrate-N under corn (Zea mays L.) increased yields of succeeding crops, but the content of nitrate-N in the soil is lower under a perennial grass stand than under corn. Lower concentrations of soil nitrate-N under timothy (Phleum pratense L.) than under corn were reported by Bizzell (1909) in New York. Increased soil nitrate-N content under corn was attributed to increased nitrification under cultivated soil. White, Dumenil, and Pesek (1958) in Iowa observed that the residual soil nitrogen one year after N application to corn was pri- marily in the form of nitrate-N in the 15- to 53-cm depth of soil. The N applications to corn did not significantly affect the level of exchangeable ammonium on the nitrifi- cation rate of soils the following spring. Yields of oats (Avena sativa L.) in 1953, however, were a linear function of N applied in 1952. Herron, g£_al. (1968) in Nebraska reported a high correlation between soil nitrate in the fall and corn yields without applied N the follow- ing year. They found most of the water or KCL extract- able N in the surface 90 cm of a silt loam soil. Grable and Johnson (1960) in Colorado reported that grass on a fine-textured soil recovered less applied N than on a coarse-textured soil. Linville and Smith (1971) in Missouri and Thomas (1970) concluded the slow leaching of nitrate under corn was influenced by a fine- textured soil. Low and high nitrate-N concentrations 62 have been associated with limited nitrification by McIntosh and Frederick (1958) in Iowa. Nitrification of 134 kg N/ha took 8 weeks on a sandy clay loam. The initial pH of 9.5 at the point of AA injection dropped to pH 5.5 after 4 weeks. Bno and Blue (1957) in Florida reported anhydrous ammonia increased the pH in a cylindrical 20- cm diameter area around the point of injection and optimum pH levels in the peripheral zone stimulated rapid nitri- fication. memick and Nilsson (1963) in Sweden also reported high concentrations of ammonia inhibited nitri- fication and oxidation of nitrite to nitrate near the point of AA release. Frederick (1956) in Indiana reported nitrification of AA increased rapidly as temperature in- creased from 6 to 15 C, and 56 kg N/ha as AN on silt loam was nitrified in two months at an average temperature of 0 to 2 C. Cassel (1970) investigated leaching of nitrate- N and found that 896 kg N/ha as AN on fallow land irri- gated with 26.7 cm of water caused a large accumulation of nitrate at a depth of 31 cm. After irrigation with 49.5 cm of water, most of the nitrate-N that accumulated at the depth of 31 cm was from nitrification of immobile ammonium. Stanley and Smith (1955) in Missouri reported ammonia retention in a silt loam was best at a soil moisture of 15 to 18%. They reported AA increased availability of P and K for a distance of 10 cm from the 63 point of injection. This distance corresponded to the distance of the pH effect. With a more economical source of N from AA than from AN, greater rates of N on grass will be applied in one application; This investigation was undertaken to study the acCumulation of soil nitratesN from anhydrous ammonia applied at four rates of N in four row spacings to a deep- and a shallow-rooted grass. B. Materials and Methods The establishment and fertilization of stands of 'Lincoln' smooth bromegrass (Bromus inermis LeyssJ and 'common' Kentucky bluegrass (Poa pratensis L.) on a Conover loam Soil was described ih Section IvB, Materials and methods. Average monthly air and soil temperatures and precipitation and irrigation added are also presented in Table l of Section I-B. The grasses were fertilized (as described in Section I) with anhydrous ammonia (AA) on April 29, 1971, and with ammonium nitrate (AN) in split applications between May 7 and July 14, 1971. Chemical and physical determinations made on April 29, 1971, in the upper 15 cm of the soil were as follows: ' k h K if? PH 6.5 P 105 CEC 4.8 Ca 1363 Bulk density 1.38 Mg 206 Base saturation 84% Soluble salts 15 Soil moisture 12% 64 The soil temperature at a depth of 10 cm under grass was 10 C at 5 p.m. on April 29, 1971. Samples for soil nitrate-nitrogen (nitrate-N) analyses were taken on both grasses in the summer and fall of both years. Samples were taken to a depth of at least 1.5 m on the following: A. At random on AN plots B. Over the 76-cm AA rows C. Midway between 76—cm AA rows. N Sampling dates kg/ha July 12, November 4, July 1 November 13, 1971+ 1971++ 1972+4 1972++ o A A A A 112 ABC ABC ABC AB 224 ABC ABC ABC AB 448 ABC ABC ABC AB 896 - AB+++ AB AB + I 0 Four replications. ++ . - Three replications. +“'One replication on AN. A Giddings Model GSR hydraulic soil-coring machine mounted on a tractor or a pick-up truck (Figure 16) was used to remove soil cores. A 5 x 152 cm soil core was taken from each 1.9 x 9.1 m grass plot. New areas of the plots were sampled on succeeding sampling dates. Soil cores similar to the core shown in Figure 17 were divided into lS-cm increments and a 10-cm portion 6S Figure 16. Hydraulic soil-coring machine with a quick release bit on the end of a‘ll x 152 cm soil tube. L k , ,7 O1. 7 . i O i , , O77 fl, Figure 17. Typical soil profile shown with 9 and 11 cm diameter soil tubes and a measuring trough used to divide the profile into 15wcm incre- ments. 66 from the mid-section of each increment was taken as a sam- ple. Samples were dried with forced air for 24 hours at 70 C, ground to pass a 2-mm sieve, and stored in paper bags until analysis. The nitrate-N was determined on soil samples by the electrode method described by Bremner, Bundy, and Agar- wal (1968) and was modified by use of a saturated calcium sulfate extracting solution. Fifty milliliters of extract- ing solution were added to 20 g. of soil and shaken for 30 minutes. Standards were prepared with KNO3. Constant stirring of the solution with a magnetic stirrer was necessary for accurate electrode readings. Results were converted from ppm nitrate-N to kg N/ha on the basis of 2.5 million kg soil in a 15-cm depth of soil in a hectare. C. Results and Discussion fi First Year (1971) From the time of fertilizer application to July, 1971, soil nitrate-N had leached to a depth of 30 to 45 cm under both grasses at all rates as AA, and under the 448vkg N rate as AN (Figures 18a, 18b, 19a, and 19b, and Appendix Table 3). This "zone" of nitrate-N concentra- tion under the AA rows and AN indicated only part of the N applied had been used by the grasses. Grass color, height, accumulation of plant nitrates, and yield increases discussed in Sections I and II also indicated the grasses 67 88 JULY I97| 88 NOV. l97l 30- 6| §¢/+—+—t DY éfi \”\ D\. \\\\E N,4/29/7L Kg/ho + NoN ff? ggaG—Ea‘i \ . ”0.05 0 IIZ '22 __ LAG +21 kg _ +55 kg 0 224 ,,35 kg \1 \ H54 kg A 448 ‘5 , \ I3 896 " '52 b 1 0 .1A 1 1 .. PI?" 1 1 1 1 4 1 J E o 40 0 4o 80 120 |60 Lu 38 JULY l972 SB NOV. |972 o AD ill/D ‘3 301 No L AU 8 l /\ | \ 0A 0 A 0 6| - tall fescue > reed canarygrass > orchardgrass > bluegrass. 9. Row spacings of AA from 25 to 102 cm had no effect on total two-year yields of the deep-rooted grasses. 10. Bluegrass yielded less at the two widest spac- ings of AA at all rates of A except at the lowest rate of 112 kg/ha. 11. Percentage of stimulation by N of the grasses between 102'cm rows of AA at the 224-kg N rate by the third cutting in the first year were: OG (84), SB (83), RC (76), 79 TF (74), and KB (66). As the N rate increased to 448 and 896 kg/ha or row spacings decreased to 51 and 25 cm, grasses were stimulated on 100% of the area. II PLANT NITRATES l. Orchardgrass had the highest concentrations of nitrate-N, whereas tall fescue, reed canarygrass, and brome- grass had similar intermediate concentrations. Bluegrass always had lowest concentrations. 2. Levels of nitrate-N in each grass species were similar as row spacing of AA increased from 25 to 76 cm. 3. By June 10, six weeks after initial fertiliza- tion, higher plant nitratevN concentrations were found in grasses fertilized with AA than with AN at N rates of 224 kg, but at the 448vkg rate of N, grasses fertilized with AN had higher nitrate«N concentrations. Orchardgrass at the 112- and 224—kg rates of N had 0.135 and 0.191% nitratevN, res- pectively, twice that of the other deep«rooted grasses. 4. By July 23, twelve weeks after fertilization, nitrate—N levels were higher in all grasses with AA at 112 and 224 kg N, equal at the 448«kg N rate, but higher with AN at the 896«kg N rate. At the 112«kg rate of N as AA all grasses were below 0.15% nitratevN (accepted "safe" for livestock), but only bluegrass and reed canarygrass were ”safe" at 224 kg N/ha. 80 5. Grasses, especially orchardgrass, increased in nitrate-N from June 10 to July 23 of the first year with greatest increases with highest amounts of applied N. 6. On both sampling dates of the first year, all grasses except tall fescue fertilized with 112 and 224 kg N as AN had less than 0.15% nitrate«N. Grasses fertilized with 112 kg N as AN had levels of nitrate-N similar to the check by July 23. 7. Grass fertilized with AA had higher nitrate-N levels than from AN in the second year. 8. Percentages of nitratevN were generally well below the safe nitrateaN level for all grasses on May 25 of the second year, and remained low on July 21. 9. Levels of nitratevN in orchardgrass were lower than in the other deepcrooted grasses in the second year. III SOIL NITRATES l. The deepvrooted bromegrass removed more total soil nitrate-N from the upper 76 cm of the soil profile than the shallow-rooted bluegrass. 2. Three months after N application, nitrate-N had leached to a depth of 30 to 45 cm under AA and AN. 3. From July to November of the first year, the accumulation of nitratevN was greater from AA than from the AN source of N. 81 4. At the 112- and 224-rates of N as AN, the N had been used by the grasses by November of the first year, but there was still nitrate«N at the 30- to 45-cm depth under AA fertilization. 5. In the first year at rates of 448 and 896 kg/ha of N, leaching below the root depth occurred because the additional N was not used by the grasses. 6. NitratevN from all rates of N remained in the upper 76 cm of the soil in November of the first year with the exception of the high rates of AN on bluegrass where nitrateNN leached to a depth of 122 to 152 cm. 7. In the second year, the nitrate-N content of the soil under both grasses was higher from AA than AN. 8. Total nitrate'N content of the soil to a depth of 152 cm was lower in the second than in the first year. 9. Soil nitrateoN moved downward in the soil pro- file in a band under rates of 448 and 896 kg N/ha and accumulated at depths of 96 to 137 cm under AN, and 76 to 107 cm under AA at the end of the second year, 18 months after fertilization with N. This nitrate—N was at or exceeded the depth of 122 cm, determined as the maximum root depth of bromegrass. This nitrate—N could contribute to ground water contamination. 10. Eighteen months after N fertilization, the soil nitratevN was still accumulating from the AA source of N in the surface 76 cm while no nitrate—N was accumulating from the AN source of N. 82 Anhydrous ammonia is as effective as AN for increas- ing two-year total yields of grass, because more residual soil nitrate«N is available for grass use in the second season from AA than from AN. A rate of 224 kg N/ha as AA is a desirable rate because in the first season grass yields are near optimum, safe levels of nitrate-N in the foliage are maintained, and levels of nitratevN in the soil that could potentially contaminate ground water do not accumulate. Leaching losses of the soil nitratevN are less with AA than AN at 448 kg N/ha under the shallow-rooted bluegrass, while the deep-rooted bromegrass at 448 kg N as AA removes more nitrate-N and significant levels of soil nitratevN do not accumulate after two seasons. The 896 kg N rate with AA and AN significantly increased levels of nitrate-N in the soil, and could contaminate ground water. LITERATURE CITED LITERATURE CITED Andrews, W. B. 1956. Anhydrous ammonia as a nitrogenous fertilizer. Advances in Agron. 8:61-125. Andrews, W. B., J. A. Neely, and F. E. Edwards. 1951. Anhydrous ammonia as a source of nitrogen. Mississippi Agr. Exp. Sta. Bull. 482. 39 p. apGriffith, G. 1960. The nitrate nitrogen content of herbage. I. Observations on some herbage species. J. Sci. Food Agr. 11:622—626. Bizzell, J. A. 1909. Some conditions affecting nitrifi- cation in Dunkirk clay loam. Proc. Amer. Soc. Agron. 1:222-227. Bremner, J. M., L. G. Bundy, and A. S. Agarwal. 1968. Use of a selective ion electrode for determination of nitrate in soils. Anal. Letters. 1:837-844. Burton, G. W., and J. E. Jackson. 1962. Effect of rate and frequency of applying six nitrogen sources on coastal bermudagrass. Agron. J. 54:40-43. Cassel, D. K. 1970. Solute movement in soils: I. Leach- ing of nitrate in irrigated fallow soil. North Dakota Farm Res. 28:15-17. Cowling, D. W. 1968. Ammonia as a source of nitrogen for grass swards. J. Brit. Grassland Soc. 23:53-60. Crawford, R. F., W. K. Kennedy, and M. J. Wright. 1960. Nitrate in forage crops and silage-benefits, hazards, and precautions. Cornell Univ. Misc. Bull. 37. 15 p. Crawford, R. F., W. F. Kennedy, and W. C. Johnson. 1961. Some factors that affect nitrate accumulation in forages. Agron. J. 53:159-162. ~ Dotzenko, A. D., and K. E. Henderson. 1964. Performance of five orchardgrass varieties under different nitrogen treatments. Agron. J. 56:152-5. 83 I'lllildlI IIII II III? ' ..I 84 Drysdale, A. D. 1970. Anhydrous ammonia as a grassland fertilizer. XI Int. Grassland Cong. Proc. (Sur- fer's Paradise, AustraliaL April 13-23, pp. 424- 427. Eno, C. F., and W. G. Blue. 1957. The comparative rate of nitrification of anhydrous ammonia, urea, and ammonium sulfate in sandy soils. Soil Sci. Soc. Amer. Proc. 21:392-396. Frederick, L. R. 1956. The formation of nitrate from ammonium nitrogen in soils: 1. Effect of tempera- ture. Soil Sci. Soc. Amer. Proc. 20:496-500. George, J. R., C. L. Rhykerd, G. O. Mott, R. F. Barnes,.and C. H. Noller. 1972. Effect of nitrogen fertiliza- tion of Festuca arundinacea Schreb. on nitrate nitrogen and protein content and the performance of grazing steers. Agron. J. 64:24-26. Grable, A. R., and D. D. Johnson. 1960. Efficiency of recovery of applied nitrate nitrogen by perennial ryegrass from different soils. Soil Sci. Soc. Am. Proc. 24:503-507. Hansen, C. M., M. B. Tesar, and L. S. Robertson. 1970. Anhydrous ammonia sod knife applicator design. Anhydrous ammonia symposium, National College of Agri. Eng., SILSOE, Bedford, U. K. Herron, G. M., G. L. Terman, A. F. Dreier, and R. A. Olson. 1968. Residual nitrate nitrogen in fertilized deep loess-derived soils. Agron. J. 60:447-481. Hill, R. M., and C. W. Ackerson. 1964. Nitrate in cattle feeds can be deadly. Nebraska Agr. Exp. Sta. Quart. Summer, p. 3-5. Hill, W. B., and B. B. Tucker. 1968. A comparison of in- jected anhydrous ammonia into bermudagrass sod com- pared to topdressed applications of urea and ammonium nitrate. Soil Sci. Soc. Amer. Proc. 32:257-261. Hojjati, S. M., T. H. Taylor, and W. C. Templeton, Jr. 1972. Nitrate accumulation in rye, tall fescue, and bermudagrass as affected by nitrogen fertiliza- tion. Agron. J. 64:624-627. 85 Jeater, R. S. L. 1967. Comparisons of liquified (anhydrous) ammonia and ammonium nitrate as nitrogenous fertili- zers for grassland. J. Brit. Grassland Soc. 22: 225-229. Kennedy, W. K. 1960. Nitrogen fertilization on meadows and pastures. Bull. 935. Cornell Univ. Agr. Exp. Sta. N.Y. State Coll. of Agr.,Ithaca, N. Y. Larson, K. L., J. P. Carter, and E. H. Vasey. 1971. Nitrate-nitrogen accumulation under bromegrass sod fertilized annually at six levels of nitrogen for fifteen years. Agron. J. 63:527-528. Lechtenberg, V. L., H. J. King, G. O. Mott, and D. A. Huber. 1970. Effect of anhydrous ammonia on the composi- tion and yield of Bromus inermis and Dactylis glomerata. Agron. Abstr., Ann. Meetings, mer. Soc. Agion. ‘Aug. 23—27. Tucson, Ariz., p. 76. Linville, K. W., and G. B. Smith. 1971. Nitrate content of soil cores from corn plots after repeated nitro- gen fertilization. Soil Sci. 112:249-255. Look Kin, W. K., and A. F. MacKenzie. 1970. Effect of time and rate of N applications on yield, nutritive value index, crude protein, and nitrate content of brome- grass. Agron. J. 62:443-444. Lucey, R. F. 1959. Effects of frequency and rate of irriga- tion, fertilization, and clipping treatments on yield and botanical composition of several forage species. Ph.D. Thesis, Michigan State Univ. (Libr. Congr. Card No. Mich.61-ll45). McIntosh, T. H., and L. R. Frederick. 1958. Distribution and nitrification of anhydrous ammonia in a nicollet sandy clay loam. Soil Sci. Soc. Amer. Proc. 22: 402-405. McVicker, M. H., W. P. Martin, I. E. Miles, and H. H. Tucker. 1966. Agricultural anhydrous ammonia. Amer. Soc. Agron., Madison, Wis., 314 p. Madison, J. H. 1972. Nitrate critical range studies of blue, bent, and Bermuda turfgrasses using the nitrate electrode. Agron. Abstr., 1972. Ann. Meetings, Amer. Soc. Agron. Oct. 29-Nov. 2, Miami Beach, Fla., p. 64. 86 Mitchell, W. H. 1967. Influence of cutting heights, irri- gation and nitrogen on the growth and persistence of orchardgrass. Agr. Exp. Sta., Univ. of Delaware Bull. 364, 15 p. Murphy, L. S., and G. E. Smith. 1967. Nitrate accumula- tions in forage crops. Agron. J. 59:171-174. Nommik, H., and K. O. Nilsson. 1963. Nitrification and movement of anhydrous ammonia in soil. Acta Agr. Scand.l3:205-219. Ogus, L., and R. L. Fox. 1970. Nitrogen recovery from a soil profile by Bromus inermis. Agron. J. 62:69-71. Paul, J. L., and R. M. Carlson. 1968. Nitrate determina- tion in plant extracts by the nitrate electrode. J. Agr. Food Chem. 16:766-768. Power, J. F., J. Aless, G. A. Reichman, and D. L. Grunes. 1972. Effect of nitrogen source on corn and brome- grass production, soil pH, and inorganic soil nitro- gen. Agron. J. 64:341-344. Ramage, C. H., C. Eby, R. E. Mather, and E. R. Purvis. 1958. Yield and chemical composition of grasses fertilized heavily with nitrogen. Agron. J. 50:59-62. Reynolds, J. H. 1969. Carbohydrate reserve trends in orchardgrass (Dactylis glomerata L.) grown under different cutting frequencies and nitrogen fertili- zation levels. Crop Sci. 9:720-723. Reynolds, J. H., C. R. Lewis, and K. F. Laaker. 1971. Chemical composition and yield of Orchardgrass forage grown under high rates of nitrogen fertilization and several cutting management. Tennessee Agr. Exp. Sta. Bull. 479, 27 p. Ryan, M., W. F. Wedin, and W. B. Bryan. 1972. Nitrate-N levels of perennial grasses as affected by time and level of nitrogen application. Agron. J. 64:165-168. Smith, D., and J. M. Sund. 1965. Influence of stage of growth and soil nitrogen nitrate content of herbage of alfalfa, red clover, ladino clover, trefoil, and bromegrass. J. Agr. Food Chem. 13:81-84. Smith, G. E. 1970. The nitrate panic button--what are the facts? Michigan Fertilizer Conf. Proc., East Lansing, Michigan. 87 Stanley, F. A., and G. E. Smith. 1955. Proper application improves value of NH3. Agr. Ammonia News April-June Tech. Bull. AA-8, 4 p. Stewart, B. A. 1970. A look at agricultural practices in relation to nitrate accumulation. p. 47-60. In 0. P. Engelstad (ed.) Nutrient mobility in soils: Accumulation and losses. Special Publ. No. 4, Soil Sci. Soc. Amer., Madison, Wis. 81 p. Tesar, M. D., C. M. Hansen, and L. S. Robertson. 1971. Anhydrous ammonia fertilization of grasses. Agron. Abstr. Ann. Meetings, Amer. Soc. Agron. Aug. 15- 20, New York, N. Y., p. 39. Tesar, M. D., C. M. Hansen, and L. S. Robertson. 1972. Increasing grass yeilds with anhydrous ammonia (Progress report). Michigan Agr. Exp. Sta. Res. Rep. 166, pp. 99-102. Thomas, G. A. 1970. Soil and climatic factors which affect nutrient mobility. p. 20. In 0. P. Engel- stad (ed.) Nutrient mobility in soils: Accumula- tion and losses. Special Publ. No. 4. Soil Sci. Soc. Amer., Madison, Wis. 81 p. U.S. Department of Agriculture. 1970. Agricultural Prices, SRS, April 15, 1970. Van Burg, P. F. J., G. D. Van Brakel, and J. H. Schepers. 1967a. The agricultural value of anhydrous ammonia on grasslandzexperiments (1963-1965). Netherlands Nitrogen Tech. Bull. No. 2. March, 1967, 31 p. Van Burg, P. F. J., G. D. Van Brakel, and J. H. Schepers. 1967b. The agricultural value of anhydrous ammonia on arable 1and:experiments (1963-1966). Netherlands Nitrogen Tech. Bull. No. 3, May, 1967, 39 p. Wagner, R. E. 1954. Legume nitrogen versus fertilizer nitrogen in protein production of forage. Agron. J. 46:233-237. Washko, J. B., and L. F. Marriott. 1960. Yield and nutri- tive value of grass herbage as influenced by nitro- gen fertilization in the Northeastern United States. VIII Int. Grassland Cong. Proc. (Reading, U. K.), July 11-21, pp. 137-141. 88 1958. Evaluation White, W. C., L. Dumenil, and J. Pesek. 50:255- of residual nitrogen in soils. Agron. J. 259. Wright, M. J., and K. L. Davison. 1964. Nitrate accumula- tion in crops and nitrate poisoning in animals. Advance Agron. 16:197-247. APPENDIX 89 MN MO OM ON MO MO OO NO ON MO MN OO Oww om oN om mo ow oN Nm om om mN Hw oN wNN mH om mH Nm mH om mH NN mH No o oN NHH oN wm wo ow oo om wo ow mo mm om mm mo m>< OO OOH OO OO OOH OOH MO OOH OO OO OO OOH OOO ON NO MO NO NO OO OO OO MN MO OO OO Oww MM MO OM OO ow NO MH NO NM OO ow OO wNN OH OO O ON O OO O OO OH MN NH wO NHH HM MM OOH OM OO NM OOH Ow OOH MM OOH OM OOH O>< OO OOH MO OOH OOH OOH wO OOH OOH OOH OOH OOH OOO OO OOH NN OOH MO OOH ON OOH ON OOH OO OOH Oww MN OOH NN OOH OM OOH OH OOH MN OOH MM OOH wNN wH OOH O NO OH OO O OOH NH OOH NH OOH NHH MN NNOH HNOH NNOH HNOH NNOH HNOH NNOH HNOH NNOH HNOH NNOH HNOH m:\OH Eu ON .OO +mmmpwosHO +osomow +mmeO 1mmmHONHmcmo.+mmmHOoEomn .oumm z .OcHomOO .OO .OO O>< NHUSanx HHmN .Opmaogo Ooom :OooEO .HNOH .ON HHNO< :o 2 mo mopmg usom um OmHHmaw << wo mmcH -ommm Son 930% :oozuon mommmHO wo HOOHo: Ocm HoHoo NO mpmoN ozu :H pmo>pwn Homo um NHHOSmH> Ooump .owmuzoopom :H .2 NO mommmhm mo :OHumHDEHum oOmho>< .H oHOmN xHOcoOO< 90 .mcoHumoHHOop Naom Eoyw pmoN sumo mOCHpuso muggy mo oOmHo><+ wM OO MN NM MH MM HO NN MM wH MM OO OO wO OO wO ON HN MO MN OO NM OO OO Mw NO OM OM NH ow ON Ow ON MH OM NN OO HO wO NN OO HO ON NO OM ww HN OO NM OO ON NM MH NM NO NO OM OH OO OOH wO NO OO HO ON NO HO HN NO wM ON OO Ow OO OO OH OH Mw NO MN wH OH Ow OO NO MO HO MO OO MN MO OO OO OO NO OO wM NO wN MM MH MM NO NN wM MH wM OO wO MO NO NO MN OO wO ON MO wM ON OO OM OO OO Hw MH OO OO NO Ow NH MM MO OO OO HO NO MO MN OO ON ON OO wO MO O>< OOO Oww wNN NHH O>< OOO Oww wNN NHH O>< OOO HH< NOH l. l I ..I‘ III III III. {III .. 91 OOH OOH OO OOH OOH OOH OOH Oww NO MO HN ON MO OO OO wNN ON MO OM OO OO OO MO NHH ON oo mo oo oo oo mo ooH m>< OOH OOH OOH OOH OOH OOH OOH OOO OOH OOH OOH OOH OOH OOH OOH Oww OOH OOH OOH OOH OOH OOH OOH wNN MO MO MO MO MO OO OOH NHH HM ooH ooH ooH ooH ooH ooH ooH m>< OOH OOH OOH OOH OOH OOH OOH OOO OOH OOH OOH OOH OOH OOH OOH Oww OOH OOH OOH OOH OOH OOH OOH wNN OOH OOH OOH OOH OOH OOH OOH NHH MN HH< OO.OO.ON.OM mmmpmosHO mmththcmo mmth osomom mmmHOothO mO\Ox Eu O>< O>< Nxospcox Oowm OHmOoHO HHmN OuooEO .mme z .OcHumOM .HNOH .ON HHHO< :o 2 mo mmump Naow pm OOHHOOm << mo mmcHomOm 30p paow coozuoO mmmpm mo HOOHoO Ocm HoHoo NO .HNOH .ON OOOOHUO OHHOSMH> Ooumu .OOOHCOUNOO OH .2 NO mmmmmHO mo coHuwHSEHum+mOmHo>< .N oHOmN xHOGOOO< 92 mnoHpmoHHmoh Naom+ MO OOH OO OO wO MO OOH OO NN OO OO OOH wO OOH OO HO OO MO OOH NO ON OO NO OOH OO OOH MO wO NN ON OOH HO OO MM NO OOH wO OOH OO OO OO wO OO HO ON HN NO OOH MO OOH OOH wO NO OO OOH OO wO OO MO OOH HO OOH OO OO ON HO OOH MO wN OO NO OOH OO OOH OO MO HO NO OOH MO MO OO MO OOH O>< OOO Oww wNN NHH O>< OOO Oww wNN NHH O>< OOO HH< .O>< NOH 93 NN w wOH OHM OM ON NNw ONN wN OM OON NOH ON ON OHH OMH HOHON mm A AA A A AA om A A om oH .A A ow o NmH-AmH Ho HH AA A A NN mH N w AN . om N A mH mH AmH-NNH Ao oH oH HH A mH AN w w NA mH N A mH oH NNH-AoH oA wH mH o o oH mH w w mH mH A A HH mH AoH-Ho moH AN HH w o mH mm A A HH A A A A HH Ho -oA mw om HH m A HH HH A A HH o N A mH N oA -Ho Hm mN om N w wm oH N N oH oH A A o A Ho -ow mH Hm omH A o omH mw N N ow mm m N oH mH ow -om o NA owH A OH NmH ow A N oA mm A A A Hm om -mH mH o mm A A mH o A N o mm A m A mm mH -o mmwmomzomm :Hoozm zo 02 NHDO +>02 >02 NHSO >02 NHDO >02 NHSO >02 NHSO >02 NHDO >02 NHDO . Eo NAoH HAoH NAoH HAoH NAoH HAoH NAoH HAoH gogoo oow oww wNN IIIIIIIImmH oOAMO .ooAHmao z @HH .HAOH .wH Ono o Ast .OH ocoo .ON oco A No: no mcoHHooHHOOm HHHOm :H ooHHgo mos z< ocm .HAoH .oN HHAmw so meow soImH ooHHOAm mo: << mo 2 HONHHHuhom .cmOHOon .OchcmH pmmm Ow Eon ho>0cou m :0 umOUOmoHO 2< Howcs m << m0 mon EUION hows: OquEHOHOO .mO\OH :H ZIOHONHH: mo mucsoE< .M oHOmN wacomm< 94 OMN Ow HO OM Nw OOH HH MH MN NN ONM HM ON NN NN ON OH MH OMH wON OH Nw w- OUON2m2 20 22< >02 NHSO +>02 >02 NHSO >02 NHSO >02 NHSO >02 NHSO >02 NHSO >02 NHDO . Eu NNOH HNOH NNOH HNOH NNOH HNOH NNOH HNOH OHOOO OOO wNN NHH og\mx .ooHHOOo z .OosaHucoO--.M OHOON xHanmm< 96 .oumhuH: EsHaoEEm mo :oHumoHHmoh o:O+ wNM wM wM HO OO ON w- <¢ w- NA NN HH MH OH HH wwO Ow Ow Ow Mw Mw Mw MO OON OMM Ow NN OM N wON Ow Ow NM ow ON NN ON HM N NMN NN OH HH MH HH OM HO HM ON N ON N OOH NN NN wM HM HM OH N NMH ON ON N ON N MN N MH N OH N N N N N O N N N N N MMMUDsz2 20 mN12< NHDO >02 NHSO NHsh >02 NHSO NHSO >02 NHSO >02 NHSO >02 NHSO . Mo NNOH HNOH NNOH HNOH NNOH HNOH NNOH HNOH OH 0O Oww wNN NHH MooOO oOAOO .ooHHOOo z .cmOHOqu .OchamH Hmmm um EmoH H0>0cou m :0 .HNOH .ON HHHO< co mooO Eo-MH OoHHOOw << mo mzog EUION :003u0O NOBOHE HOHOO m Hmwcs OmaHEpoumO .mO\OM :H ZIOHONHH: mo mucsoe< .w oHOoA xHoaogm< 98 MO HH MH MH HH MNN OM wM NM Ow ON OH NO OH OH MH OH HH w- w- <¢ 1w w- N MM22< wNH NN ON wM MN OH HH O MHH OH ON MN HH OH MH N ON N NNH NN NN NN OH HH N OO MH N ON V? ON MNH HM NN NN NH OH HH HH OH HH HH OO ON OH MH HopoA NMHINMH NMHINNH NNHINOH NOHIHO HO 1ON ON 1HO HO IOw Ow 1OM OM IMH MH 1O IIIIIIIIIIIIIIII II “I V| I I I IIIIIIII 69 3169 5