USGA GREEN SECTION X A Publication on Turf Management by the United States Golf Association USGA GREEN SECTION RECORD A Publication on Turf Management by the United States Golf Association © 1968 by United States Golf Association. Permission to reproduce articles or material in the USGA GREEN SECTION RECORD is granted to publishers of newspapers and periodicals (unless specifically noted otherwise), provided credit is given the USGA and copyright protection is afforded. To reprint material in other media, written permission must be obtained from the USGA. In any case, neither arti­ cles nor other material may be copied or used for any advertising, promotion or commercial purposes. VOL. 6 No. 3 SEPTEMBER 1968 Winter Protection for Automatic Controllers by Lee Record............................. 1 The Story of Cohansey by E. R. Steiniger.................................................................. 3 The Correct Sand for Putting Greens by Charles G. Wilson............................... 8 Lessons Learned in Automatic Irrigation by John H. Madison.......................... 10 Turf Twisters ..................................................................................................... Back Cover Published six times a year in January, March, May, July, September and November by the UNITED STATES GOLF ASSOCIATION, 40 EAST 38th ST., NEW YORK, N. Y. 10016. Subscription: $2 a year. Single copies: 35(1. Subscriptions and address changes should be sent to the above address. Articles, photographs, and correspondence relevant to published material should be addressed to: United States Golf Association Green Section, P.O. Box 567, Garden Grove, Calif. 92642. Second class postage paid at New York, N. Y. Office of Publication: 40 East 38th Street, New York, N. Y. 10016 Editor: William H. Bengeyfield Managing Editor: Robert Sommers Cover Photo: A time-saving and neat job of installing auto­ matic irrigation systems is possible by the new technique of “pulling pipe” through the ground without need for dig­ ging ditches. This “instant” way to course watering with flexible pipes is one more in­ novation in the trend toward complete irrigation of golf fairways. See the article by John H. Madison on automatic irrigation starting on Page 10. THE GREEN SECTION OF THE UNITED STATES GOLF ASSOCIATION Green Section Committee Chairman; Henry H. Russell, P.O. Box 697, Miami, Fla. 33157 Green Section Agronomists and Offices EASTERN REGION Eastern Office: P.O. Box 1237 Highland Park, NJ. 08904 Alexander M. Radko, Director, Eastern Region and National Research Director A. Robert Mazur, Eastern Agronomist James W. Timmerman, Eastern Agronomist SOUTHERN REGION Southern Office: P.O. Box 4213, Campus Station, Athens, Ga. 30601 James B. Moncrief, Director, Southern Region Holman M. Griffin, Southern Agronomist MID-CONTINENT REGION Mid-Continent Office: Room 905, 211 East Chicago Avenue, Chicago, III. 60611 James L. Holmes, Director, Mid-Continent Region F. Lee Record, Mid-Continent Agronomist WESTERN REGION Western Office: P.O. Box 567 Garden Grove, Calif. 92642 William H. Bengeyfield, Director, Western Region and Publications Editor Cold weather covering of automatic control center for watering systems is easily achieved as shown above. A plastic bag is first placed over the console (Figure 7, left). A heavy insulation material (Figure 2, center) next goes over the plastic cover. Finally the whole thing is enclosed in a wooden box built to fit securely over the unit (Figure 3, right). Winter Protection for Automatic Controllers by LEE RECORD, Agronomist, USGA Green Section T he golf course superintendent has learned a great deal about the installation, the flexi­ bilities and reliabilities of automatic watering systems. One of his most important realiza­ tions is that the automatic controller is the “brain” of the system and therefore must be functional at all times. During the spring or early summer periods when desiccation is most prevalent on many Eastern courses, little can be left to chance. The insured protection of the controllers, which are scattered throughout the course, now be­ comes an important factor in the success the golf course superintendent will have with his turfgrass maintenance program. Winter months are the most critical time of year for the controller, for this is when dam­ age may occur most easily. Although the con­ trollers are not needed at this time for distri­ bution of water, the accumulation of moisture and rust formation on working parts may lead to unnecessary deterioration of the mecha­ nisms. This in turn can lead to the failure of the early spring irrigation program. SEPTEMBER, 1968 1 This added protection assures Capstick that when spring comes his controllers will be op­ erational. Should he have to work on the con­ trollers during the winter, it is easy to remove the wooden box, insulation, and plastic bag without chipping ice away from hinges or thawing out the lock. The chance of moisture getting into the controller, causing rust or hindering working parts, is minimal. In Figure 4 we find what Vernon Burnham, Superintendent of the Country Club of Darien, Darien, Conn., does for the added protection of his controllers. By placing a 55-gallon drum over each controller, he has obtained excel­ lent results in keeping the elements of nature away from the controllers on his course and preventing damage. Even though Capstick and Burnham have additional protection for their controllers, they recognize the importance of continuing to cycle them during the winter. One of the more common practices is to cycle them from 1 5 to 30 minutes daily, while other practices call for continuous cycling for the entire winter. Manufacturers are continuing their efforts to assure operational success of their equipment. In addition, the golf course superintendent must still use his ingenuity to give added pro­ tection to meet his own local conditions. Solution of Crossword Puzzle for Last Issue Another way of protecting automatic control­ lers is to use a large steel barrel over the unit to keep out harsh weather (Figure 4). Controllers stand like pyramids facing all elements of nature: freezing rain, sleet, bliz­ zards and the accumulation of drifting snow. Therefore, additional protection, above that already provided by most manufacturers, must be furnished. Manufacturers of various controllers now on the market have built-in safety factors which will cut down on moisture, rust damage, etc. Heating elements and rust-proofing of the controller are two of the basic requirements now provided. Bob Capstick, Superintendent of the Coun­ try Club of New Canaan, New Canaan, Conn., has given every consideration to the protec­ tion of his controllers throughout his course. Figure 1 shows the first step Capstick employs, putting a plastic bag over the controller. In Figure 2 heavy insulation is placed over the plastic bag. Figure 3 is the final step. He has constructed a wooden box to fit snugly and securely over the controller. 2 USGA GREEN SECTION RECORD Pine Valley’s pie green fest area (Figure 1), providing a close comparison of different putting green turfgrasses, shows how an early strain of C-7 was rated. The Story of Cohansey by E. R. STEINIGER, Superintendent, Pine Valley Golf Club, Clementon, N. J. |n 1933 an outstanding patch of creeping bentgrass was first observed on our fourth green of Pine Valley, which is an old South German mixed bentgrass green. In 1935, after close watching and recording the behavior of this strain, one square foot of it was planted in our nursery along with other selected strains. Later in the year the first sizable plot (3,500 square feet) was established in our turf garden. Its fine texture and upright growth made it a fine putting green turf, and its light green color was pleasing to see. In 1939 Dr. John Monteith, Jr., and Fred V. Grau introduced this strain into the turfgrass gardens at Arlington, Va., and designated it as C-7. The “C” designation was the code for creeping bentgrass selections tested by the Green Section. C-7 did very well at Arlington, and later at Beltsville, Md., except for a little dollar spot; in fact it did so well that prior to World War II, when the “pie greens" (Fig­ ure 1) were laid out all over the country by the Green Section, C-7 was included. The performance of the nationwide tests was re­ ported in the June, 1944, issue of the Green Section’s publication “Timely Turf Topics" as follows: Four-Year Summary of Ratings of Creeping Bents in Experimental Greens “Data from the experimental greens estab­ lished in 1 939 and 1 940 by the Green Section in many parts of the country have been sum­ marized during the past winter. Since the summaries reveal much of interest to those responsible for putting greens now and in the postwar period, it seems advisable at this time to publish some of the inescapable conclusions. “For those who are not acquainted with SEPTEMBER, 1968 3 these experimental greens it may be stated that the typical green is composed of 1 2 or more wedge-shaped sections, each planted with a single strain of creeping bent. So far as possible the greens were used throughout the test period as regular or practice greens so as to expose each of the grasses to the cus­ tomary wear and tear of play. For comparison purposes each green contained wedges of one or more of the three commercially available vegetative strains — Washington bent (C 50), Metropolitan bent (C 51), and Old Orchard bent (C 52). “In addition, sectors were planted with one or more of the following commercially avail­ able seed: Seaside creeping bent (C 60), As­ toria Colonial bent (C 61), and Highland Colonial bent (C 65). The remaining sectors were planted vegetatively with strains of creeping bent which had been assembled by the Green Section from various parts of the country and had proven most promising in the tests over a period of years in plots main­ tained under putting green conditions in the trying climatic conditions on the turf garden at Arlington, Va. Usually only six or seven of these strains were included on any one green. In all, 19 strains were tried on one or more of these experimental greens. “They are as follows: Club Where Found Originally Strain 0 1 C4 Country Club of Atlantic City Arlington Turf Garden City Atlantic City Arlington State NJ. Va. Date 1928 1934 1936 Calif. Beverly Hills Long Branch Ontario 1936 Long Branch Ontario 1936 1936 Springfield Pa. Clementon Baltimore C5 C8 C7 C9 C12 Arlington Arlington Arlington 014 C 15 C16 Arlington Turf Garden Pine Valley Golf Club Baltimore Country Club Washington Golf & Country Club Cll Washington Golf & Country Club Los Angeles Country Club Toronto Golf Club Toronto Golf Club Rolling Green Golf Club Manor Country Club Norbeck Congressional Bethesda Country Club C27 Washington Golf & Country Club C28 Washington Golf & Country Club Congressional Country Club Manor Country Club Norbeck Manor Country Club Norbeck Arlington Arlington Turf Garden Bethesda Arlington Arlington C 17 C 19 C32 C35 C36 C38 Va. N.J. Md. Va. Va. 1934 1935 1935 1936 1936 Md. Md. Va. Va. Md. Md. Md. Va. 1936 1936 1937 1937 1936 1937 1937 1937 Commercial Strains C 50 — Washington bent 0 51 — Metropolitan bent 0 52 — Old Orchard bent C 60 — Seaside bent C61—Astoria bent 0 65 —Highland Colonial bent “It will be recalled that, at the request of the Green Section, the grasses were rated in order of preference, all characteristics, both favorable and unfavorable, being considered. The most desirable grass was rated as 1, and the least desirable as 1 2 (when, as was usu­ ally the case, 1 2 grasses were under test on the green). It was hoped that the ratings ABOUT THE AUTHOR Eberhardt R. Steiniger has been at Pine Valley continuously since 1927 (except for military duty World War II). Eb, as he is known to turf people all over the world, is a man of unusual personality with a spark that generates interest in all fields when he is on the scene. Mr. Steiniger is Vice-President of the Pennsylvania Turfgrass Council; Chair­ man of the Joe Valentine Memorial Fund; Past President of the Philadelphia Association of Golf Course Superintendents and he is active in the civic affairs of Camden, New Jersey. He serves on the USGA Green Section Committee. 4 USGA GREEN SECTION RECORD would be made at intervals throughout the growing season so that progressive seasonal changes in the relative ratings of the grasses might be followed over a period of years. “In order to summarize the results, all of the ratings for each climatic season during which the grasses were actually growing (spring, summer and fall) were averaged for each green. Consequently a green which was estab­ lished in the spring of 1939 had a possibility of 14 seasonal averages through the fall of 1943. “It is noteworthy that of the 23 greens es­ tablished in that year, only one experimental green enjoys the distinction of having that number of seasonal ratings to its credit. Also, only one of the remaining greens which were established either in the fall of 1939 or spring of 1940 has a perfect record since it was established. However, in spite of these facts, for some of the strains such as C 52 and C 19, which were established on 36 and 35 of the experimental greens, respectively, we have as many as 173 seasonal averages from which to draw conclusions. “Of the total number of 19 strains included on the experimental greens, five of them were tested along with the commercially available vegetatively propagated strains (Washington, Metropolitan, and Old Orchard) on 32 or more of the greens. Therefore between 150 and 175 seasonal averages have been ob­ tained for these grasses. Comparable number of seasonal averages were also obtained for the seed-propagated bents — Seaside creep­ ing bent and Astoria and Highland Colonial bents. For two other Green Section strains there were as many as 73 seasonal averages, whereas for most of the others not more than 20 are available. Since the results from so few ratings could scarcely be considered signifi­ cant, only those strains for which 70 or more seasonal averages are available are included in the accompanying summary. “In order to arrive at a satisfactory basis for comparing the relative merits of these strains, summaries were made for each season for each of the experimental greens. From these summaries it was easy to determine how many seasons on each green each strain took first, second, third, or fourth place, respec­ tively. It was believed that it might be unfair to the strains to limit the summaries to the number of times the grasses fell in first place since so much of personal prejudice is inevit­ able in the selection of the best of the superior strains. For this reason in the accompanying summary the grasses are arranged in order of the percentage of seasons in which they fell in any of the first four places. Figures also are included, however, which indicate the fre­ quency with which each strain was given first, second, third, or fourth choice, respectively. Percentage of Seasonal Averages In Which Each Strain Falls in 1st 4 Places 1st Place 2nd Place 3rd Place 4th Place 61.9 60.7 58.9 58.0 45.1 38.7 37.0 36.4 30.9 19.2 17.0 10.5 9.5 12.9 20.2 12.3 27.2 15.0 4.5 5.5 2.4 8.0 3.0 0.7 1.3 0.7 16.1 16.8 26.3 10.5 6.9 9.0 9.6 11.5 12.4 4.8 2.6 1.3 2.7 14.2 15.0 11.0 11.1 15.0 9.0 11.0 13.3 6.2 4.8 3.3 5.9 3.4 18.7 8.7 9.6 9.2 8.1 16.1 11.0 9.1 4.3 6.6 10.5 2.0 2.7 No. of Seasonal Strain Averages 155 C-7 Cohansey C-19 Congressional 173 C-36 Norbeck 73 C-15 Toronto 162 Old Orchard (C-52) 173 155 C-17 73 C-28 Washington (C-50) 165 C-l Arlington 162 Metropolitan (C-51) 167 153 Seaside (C-60) Astoria (C-61) 153 147 Highland (C-65) “A study of the table will show that the first five grasses are the superior strains, regard­ less of whether one considers their occurrence in 1st place only or in the first four places. However, the relative standing of these five superior strains is significantly different, de­ pending upon the basis of comparison. C 15 and C 7 exchange places when first place only is considered, instead of the present arrangement. C 1 9 remains in the same rela­ tive position by either method of comparison, whereas Old Orchard would move up to 3rd place instead of 5th place if compared with the other strains on the basis of 1st choice only. C 1, although 9th in order under the present arrangement would fall in 6th place if only first choices were considered. “It is obvious that in general the Washing­ ton and Metropolitan strains have been the least desirable of the vegetatively propagated creeping bent strains under test in this series of experimental greens. The seeded bents con­ spicuously are in a class by themselves at the foot of the list, although they did show possi­ bilities in Pittsburgh, Tulsa, and Portland. “It should be remembered that the figures given here represent the average behavior of the grasses in greens distributed over all parts of the country and under many types of main­ tenance programs. Therefore although a strain SEPTEMBER, 1968 5 may rate at the bottom of the list it is not surprising to find that in specific limited situa­ tions it may be a superior grass. “It appears significant that these five su­ perior strains have excelled in diverse parts of the United States. To indicate the widely dis­ tributed geographical areas in which these grasses produce superior turf, C 7 may be cited as being one of the first four choices for the entire test period on experimental greens in the following districts: two out of four in the District of Columbia; one in Virginia; one in Massachusetts; one in Ontario; two in upper New York State; one out of three in the Metro­ politan area; two in Pennsylvania; three in Ohio; one in Indiana; two out of three in Missouri; one in Detroit; four out of five in Chicago; one in Omaha; one in Tulsa; and two out of three in California. “These figures illustrate the fact that al­ though these grasses are generally superior in many parts of the country they do not neces­ sarily lead in ratings on all of the greens in any one area. It would therefore seem advis­ able before deciding to use any single or several strains which have been superior on one or more experimental greens in your vicinity to try the grasses under your specific conditions and maintenance program.” The C-7 strain was distributed to interested commercial growers in 1946, and so a name for it had to be found. Overzealous people concerned began to assign their own names, and one commercial firm erroneously assigned the name “Clementon,” after the town where Pine Valley’s post office is located. This was hurriedly retracted. Soon after, at my instiga­ tion, a contest was held among Pine Valley members and many names were suggested. Among them was “Crump” after the founder of Pine Valley, “Pine Valley,” “The Valley,” and numerous other names. After many dis­ cussions with John Arthur Brown, Pine Valley’s President, the name “Cohansey” was selected and this announcement was made: C-7 is to be named — “In trying to decide a given name of designation C-7 we came to the conclusion that the selection should be identified with a little considered element in the place where this hopeful strain was developed and not with the place itself. So excuse please if we seem to digress. “The average golfer playing on the greens and fairways of Pine Valley takes for granted the many acres of beautiful grass which he finds at that Paradise. How­ ever he is apt to give particular attention to the fast sandy traps and bunkers which he probably thinks have been created by a power something beyond that of an artistic golf amateur. But there is no warrant for taking for granted the 40 acres of greens, tees and fairways with their various types of bent and other grasses. These all grew, believe it or not, on sand. The turf has 6 USGA GREEN SECTION RECORD This is Pine Valley. The avenues to a good score seem as narrow and remote as this path in the foreground to No. 1 7 green. young hopeful C-7 but . . . Cohansey!” The thought about naming this grass Co­ hansey came to us while we were drilling some new wells for our drinking water supply. Pine Valley is blessed with good water supply and most of this water comes out of the Cohansey strata. The Cohansey strain of bent is fine-bladed, has an apple green color, is a rapid spreader, heals itself quickly after injury, grows upright, and produces a very fine-textured putting green. It has been found suitable for putting greens in all regions where bent can be grown. It is liked from Virginia to St. Louis to Oklahoma and everywhere north. Penncross bentgrass and Pennlawn fescue. He wrote numerous technical works for trade journals and articles for magazines, and was the author of Turf Management, a textbook published by the USGA. taken years of study, of topdressing and nourishment with careful watering, to with­ stand the heavy use and violent treatment which seems to be the daily burden. “Grass grown on sand needs more than a normal rainfall to retain its sparkling vigor under severe conditions and close crop­ pings. WATER is The essential element. Na­ ture in ages by and gone laid down the water courses in strata through which today comes this essential element in abundance, serving the many lakes, as well as the black water for the grasses and the white water for the players. “That water course we call “The Co- hansey.” How else should be called our H. BURTON MUSSER T he Green Section of the United States Golf Association lost a valued friend with the pass­ ing of H. Burton Musser of State College, Pa., on August 12. Professor Musser retired in 1959 as Professor of Agronomy in the School of Agriculture at the Pennsylvania State Uni­ versity and since had served as the Executive Director of the Pennsylvania Turfgrass Coun­ cil. He was a Fellow of the American Society of Agronomy. In January 1966, when he was 72 years old, Professor Musser became the sixth recipi­ ent of the Green Section Award of the United States Golf Association for “distinguished service to golf through work with turfgrass.” He was responsible for the development of SEPTEMBER, 1968 7 The Correct Sand for Putting Greens by CHARLES G. WILSON, Head Agronomist, Milwaukee Sewerage Commission Surprisingly enough, there is considerable agreement among turfgrass soil scientists on the subject of correct sand particle size to be used in construction and top-dressing of putting greens. Unfortunately, we have some­ times lowered our standards in the mistaken belief that the customer would not pay the cost of using the correct materials. This is a mistake needing correction! The right gradation and size of sand par­ ticles can be justified by the builder and the golf superintendent, as well as those who pay the bills. The first step is to refuse any sand that is retained above a 10 mesh Tyler standard screen. Materials passing through the 10 mesh size are 1.410 mm or .0555 inch or smaller. As the Tyler mesh size drops (10, 8, 6, etc.) the particles get larger. Coarse clinkers (those above 10 mesh) should be eliminated, or tol­ erated if present in only fractional percentage amounts. The reason is simple. Once the green is turfed it is virtually impossible to work any­ thing larger than .065 inches (10 mesh) into the turf fiber when the putting green is top- dressed. Suppose, for example, your course has pur­ chased a “concrete grade’’ of sand under the mistaken belief that it is cheaper because it costs less per ton or per cubic yard. Dr. Don­ ald V. Waddington at Penn State University has found that sand grades are quite variable in particle size, so let us also suppose 50 per­ cent of this sand is retained above a 10 mesh screen, a not uncommon occurrence. You mix this carefully in proper proportions with soil and humus to match the USGA soil specifica­ tions used in construction. You even compost the mixture to be sure the particles won’t sepa­ rate in the act of top-dressing. You have a physical soil analysis made just to be sure it’s the proper mix. The tests show the 7 parts sand, 2 parts peat and 1 part soil by volume in the mixture to be excellent in terms of infil­ tration and percolation after compaction. Then the greens are top-dressed. Your labor crew is a good one. They work carefully and diligently to brush, board and drag mat the top-dressing into the turf. In fact, they spend many extra hours in this attempt. But Io and behold, almost all of the coarse sand fraction is eventually carried to the green collar where it must be picked up and hauled away to create even more work. The small percent of coarse clinkers that remain on the green and on top of the grass does not escape notice. The golfers are angry, and the mechanic is paid overtime for keeping the dull mowers sharpened by extra grinding and lapping in bedknife and reel. And what of the poor grass after the dust (literally) has settled? Instead of the 7-2-1 mix originally specified and intended in this example, the grass has received a 4-2-1 ratio that makes an excellent substitute for concrete. Assuming all the peat and all the soil ap­ plied can be worked into the grass, look at what this act of removal does to our original mixture on a “by volume’’ percentage basis. The 70 percent of sand in the original 7-2-1 mixture (100 percent) drops to 57 percent con­ tact on the green after three parts of the coarse sand is hauled away. The peat in­ creases from 20 percent to 28.5 percent, and the soil content jumps from 10 percent to 14.5 percent. “Hardly the original mixture,” you say. And you are correct! Even the act of aerating and core removal prior to top-dressing won’t solve the problem, because there is still two inches of turfed area between each hole that refuses to accept the coarse sand particle. So, why not buy an acceptable sand in the first place? Penn State recommends a minimum of 80 percent in the 14-65 mesh size (1.190- 0.208 mm, 0.0469-0.0082 inches). Dr. Ray­ mond Kuntze, of Michigan State, who did the original work on the USGA specifications at Texas A & M, favored a gradation of 0.25 mm to 1.0 mm in size. This comes very close to Penn State’s suggestion. Most turfgrass soil scientists also would prefer a round sand to a sharp, angular sand where a choice is avail­ able, and in this discussion on sand we are referring only to true silicas and not some substitute such as crushed limestone or slag. Seldom will you find such a sand available without special screening. One sample we 8 USGA GREEN SECTION RECORD PARTICLE SIZE CHART analyzed from Ottawa, III., is as near perfect in “run of the pit,” as we have seen. It is ideally suited for bunkers as well as construc­ tion and top-dressing. The mesh size was as follows: Mesh 10 16 28 48 100 Pan mm 1.651 .991 .590 .295 .147 — Inches .065 .039 .0232 .01 16 .0058 — Percentage Retained 0.30 11.24 58.91 26.62 2.60 0.33 We would hold out for nothing coarser than the above 10 mesh in screen size, and only then in a fraction of 1 percent as being ac­ ceptable. We would approve as much as 20 percent falling below the 48 mesh size, but retained on a 65 mesh screen. Such a sand screened to specifications, es­ sentially passing through a 1 0 or 1 2 mesh and being retained on a 65 mesh screen will obvi­ ously cost more per ton than common concrete or mortar sand. Yet, one ton of this sand is equivalent to two tons of the sand used in our horrible example, since none is wasted in top-dressing. It is appreciated that most of the savings in freight and bulk handling will be realized after and not during construction. Although, even during construction the finer grade of sand specified should go farther because there are more particles per unit of measure now that the coarse clinkers have been removed. And just think of the fringe benefits. Less labor down time involved in top-dressing; hap­ pier golfers; and by no means last, protection in perpetuity of the putting green soil profile you so laboriously and expensively put to­ gether in the first place. Thus, one should provide a physical soil laboratory, with the competence to carry out the tests described in the USGA Green Section Specifications, with decent sand in the first place. The same can be said for humus and soil, which is another subject and too lengthy to include here. Follow the USGA Green Section specifica­ tions on mixing and construction exactly as written. And finally, each club should require an Act of Congress before anyone is permitted to tamper with or alter the soil mixture decided upon, no matter how well-meaning he may be. SEPTEMBER, 1968 9 Department of Environmental Horticulture, University of California at Davis by JOHN H. MADISON, I rrigation costs in much of the nation are second only to labor. If we can increase our capitalization with the expectation of present and future savings of labor and water costs, the long term savings may be worthwhile. Automatic irrigation systems are increasing in number, and the justification is long term economy. An automatic irrigation system has real value for the superintendent to the extent that it is a management tool. Without high management capability it may create its own costly problems. Automatic systems have not always resulted in the savings projected to justify them, and their management capability is the remaining good that can make the sys­ tem worthwhile or — by its lack — a burden. We can all recognize the good of econom­ ical operation. But automatic irrigation has come to us without our being prepared. We have not known what to ask of it in the way of management capability. We are still ex­ perimenting and improving, still discovering new things we want our system to do. We need to develop our criteria for high manage­ ment capability as soon as possible. The longer we take, the more systems will be in­ stalled that are inadequate and soon become obsolete. Here I propose six criteria I should want to use in buying a system. 1. The irrigation design should be adequate. In the Northeast where a sprinkler system is used to supplement a generally adequate rainfall, second- and third-class design is used, and is tolerable. In the irrigated West where one depends fully upon irrigation, only first-class design should be used in an auto­ matic system. The most sophisticated controller is only as good as the system it controls, and the controller cannot make up for deficiencies in the system. In the West, not only is the single fairway line wholly inadequate but also first-class agricultural sprinkler design is in­ adequate on turf. With the compaction and traffic it receives, turf has lower infiltration rates than agricultural soils. Application rates are apt to be too high, and the higher they are the more inefficient the operation, the more water is wasted. Also, agricultural crops send out roots through a large volume of soil holding hun­ dreds to thousands of gallons of water. The large root system compensates in part for inadequacies of application. More water is taken from the wet areas, less from the dry. The turfgrass plant, on the other hand, may explore only a few cubic inches of soil and have only a part of a cubic inch of water available after an irrigation. The only water available is that which enters the soil immedi­ 10 USGA GREEN SECTION RECORD ately beneath the plant. There is no adjust­ ment possible between an area that receives too little and one a couple of feet away that receives too much. Inadequacies of sprinkler irrigation are illus­ trated by a bowling green irrigation system worked out by Tom Byrne, Farm Advisor in Alameda County, Calif. After much effort to develop the best system possible, 5 per cent of the green was underwatered and 45 per cent received more than twice the needed water. This illustrates the inadequacies and inefficiencies of even the best sprinkler design. 2. The minimum programmed time should be about two weeks. There are two reasons to want this: (a) In the spring, water applied more often than needed greatly increases weed germi­ nation and establishment. (b) Deep rooted fairway grasses such as bermudagrass will conserve water — will use it more economically only if forced to by using long intervals between irrigations. Water is held with increasing tension by the soil as it dries, and bermudagrass can respond with physiological adaptations which enable it to survive and grow with less water. For these two reasons we want at least a 14-day program time. 3. Different stations within the controller must be able to have different automatic pro­ grams. Shrubs have different requirements from turf; bermudagrass requirements differ from those of bluegrass; those of shade turf from grass in the sun; those of fairways differ from those of the rough. Unless you can irrigate the grass in the shade, for example, every six days, while that in the sun is irrigated every three, you end up irrigating everything accord­ ing to the needs of the most demanding area of shallow-rooted turf. You should not have to manipulate the controls by hand every few days to get this difference in program. 4. A single station within the controller should be capable of being programmed differ­ ently (and independently) on different days. Turf has more roots near the surface, fewer at deeper depths. When the surface layer has dried, soil of the lower root zones may still contain adequate water. However, there are not enough deep roots to take up water fast enough to meet peak needs. Consequently, afternoon wilt develops. A tensiometer-con­ trolled irrigation program at UCLA has given results indicating how we may most economi­ cally apply water to use the whole root zone and still avoid mid-day wilt. Their records in­ dicate that the most economical program is one that applies about two shallow irrigations before applying a deep leaching irrigation. The controller should be able to handle this program without need to reset it. 5. There should be a ratio control so that all stations within a control box can be changed with a single setting and so that each station puts on water in the same proportion to the others as it did before. The reason for this is the wish to meet the change in demand with change of the sea­ sons. A box should be reprogrammed about 10 times a year for optimum water economy. If each station were to be reprogrammed in­ dividually, some systems I have seen would require 10 to 20 days per year of skilled management time. This discounts much of the labor saving advantages. Also, suppose you have one station set so that it controls sprinklers in the north shade and another controls heads on a sunny south slope. By trial and error you have adjusted them so that the first puts on about 35 per cent of the second, and both meet the demands of the areas they control. It is unlikely that you could reset these several times a year and still maintain this difference. As a result you would like to be able to set one control and change every station within the box by a proportionate amount. 6. The controller should be able to apply any single irrigation as a series of repeated short irrigations. One difficulty of sprinkler irrigation is that efficiency of application is obtained only at high application rates — rates that are too high. At these rates efficiency of infiltration, of use, is low. Too much water runs off and high spots are left dry. One of the great potentials of automatic irrigation is the possi­ bility of solving this dilemma. By using a high degree of overlap we can increase our effi­ ciency of application but at application rates that are too high. However, the turf mat is able to hold a fraction of an inch of water. SEPTEMBER, 1968 11 By applying water at a high rate for a short time the water is held in the sponge of the mat until it infiltrates the soil. The application is repeated again and again at spaced inter­ vals until the full application is given. The system operates at a high capacity throughout the interval it is on, but at a single spot, the mean application rate averages out to a suit­ ably low value. At present all controllers have some of the features I have asked for—none has all. The manufacturer will design a controller with what he considers to be sales features unless you can tell him what you need — what you demand. Automatic irrigation is still young, and controllers will continue to undergo a slow evolution. You can hasten that evolution with a clear statement of your needs and wants. An example of good use of existing equip­ ment to provide flexible management is pro­ vided by the new system at the San Francisco Golf Club, engineered by Don Hogan. Each station of the controller controls heads of similar elevation and exposure. Each sta­ tion is set for a short irrigation period (a few minutes) and the times are adjusted (by trial and error) to compensate for differences due to sun, shade, slope, elevation, etc., so each receives a proportion of water appropriate to the area. The entire controller is itself con­ trolled by one station of another controller in the superintendent’s office. This two echelon system permits the superintendent easily and quickly to change his program — easily to exercise management flexibility. A long irrigation is given by allowing a large number of cycles to repeat, a short one by repeating only a few cycles. With the water applied in short cycles, the effective rate of application is reduced, which helps to increase wetting of dry areas and to reduce runoff. Having a suitable automatic system is not enough. Poor use of it can lead to problems. With poor operation one often sees a tre­ mendous increase in crabgrass and other weeds during the second season of operation. A new system is not automatic in its pro­ gramming; the program must be set up by trial and error. The best tool for programming is a soil tube. You must know where the water is going, and nothing beats the soil probe for examining a large number of locations in a short time. Wet and dry soil are easily dis­ tinguished, so that you can determine how deep your water is going and whether you are wetting the entire root zone or only part of it. Once the system is programmed it still re­ quires management to achieve goals of water economy. The advertised “set it and forget it’’ exem­ plifies the abdication of management. The following offers some guidelines for manage­ ment use of an automatic system after you have it. 1. Patrol the system regularly. Operating at night the system is out of sight and often out of mind. Damaged heads, malfunctions, or vandalism may go unnoticed until they show up as dry turf. In a schoolyard a missing head went unreplaced for over a year. A geyser every night caused a permanent wet spot, and the loss of pressure created dough­ nuts around other heads. But the system was run by a custodian who was uninterested and who responded to the brown turf by increas­ ing the irrigation time. Diddling the controller will not replace a missing head. Patrol for missing or damaged heads, heads not turn­ ing, heads cocked at an angle, heads set too low so that they operate under water, or heads blocked by overgrown grass. Check nozzles periodically. An inexpensive set of drills provides a good set of plug gauges for checking nozzle sizes. At longer intervals check pressures at the nozzle with a Pitot gauge. Low pressures may indicate hidden leaks, worn nozzles, corrosion, or dirt block­ ages. 2. Start slowly in the spring. Irrigate as in­ frequently as you can, but when you irrigate, apply enough to wet through the root zone. This will assist greatly in keeping down crab­ grass and other weeds. The cracks that de­ velop as the soil becomes dry will help get the water in with reduced runoff. 3. For economical water use, change the program according to the season. Use will depend on the solar energy input. This is af­ fected primarily by the angle of the sun’s rays, length of days, and degree of cloudiness. Weekly difference in turf water use tends to be small near the solstices, large near the equinoxes. Economical water use in the irri­ gated West will require about 10 changes of program a year, each involving at least a 10 percent change in water use. In any location, East or West, close control of water applica­ 12 USGA GREEN SECTION RECORD tion can be achieved by adjusting water ap­ plication to parallel loss from a Bureau of Plant Industry evaporation pan. This is a pan six feet in diameter, 2 feet in depth, set flush with the ground and having the water sur­ face about four inches below soil level. 4. Avoid daily wetting. Daily sprinkling leads to heavy invasion of crabgrass, Poa annua, dallisgrass, and other weeds. Daily sprinkling keeps the soil at moisture levels where it is most subject to compaction from traffic. Compaction is our biggest turf prob­ lem. Daily sprinkling keeps the soil at its low­ est infiltration rate so that waste from runoff is maximum. Daily sprinkling stops the cycle of wetting and drying, shrinking and swelling which restores soil texture and aids soil aera­ tion. Daily sprinkling favors disease, buildup of lawn moths, and promotes a soft growth readily injured by stress. 5. Know when to make an exception to Number 4. Sometimes in the middle of sum­ mer two or three days of over-irrigation will stimulate the grass, help wet up dry spots, leach salts and improve appearance. Again in late August a few days of heavy irrigation may help relieve summer stressed areas so that they begin to recover. Also, when summer disease has injured roots, a daily sprinkle may keep grass alive until new roots form. 6. Decrease irrigation by increasing inter­ vals. When cutting down on water use after the summer peak, decreasing irrigation fre­ quency is preferable to giving shorter irriga­ tions. More frequent irrigation favors weeds and abuses the soil as discussed above. In addition, remember: a little water does not wet the soil a little bit — a little water wets a little soil and leaves the rest dry. Several years ago I presented some irriga­ tion design formulas based on plant soil rela­ tionships. These are very useful for checking out a system and finding weak points in it. Their usefulness is limited by the fact that often we do not have figures for evapotranspiration and infiltration rates to insert into the formula. However, if we are concerned with the worst month in the worst year in a series of dry years, we can use an ET figure of 2 inches per week and an infiltration rate guessed at 0.1 inch per hour. For a low ET and a high infil­ tration rate we can use 1 inch per week and 0.5 inch per hour as exploratory values. Even though inaccurate, these values used in the formulas will often point out system weak­ nesses and indicate the kind of compromises that will need to be made. (1) Evapotranspiration (in/week) Infiltration rate (in/hour) Hours per week = water must be on an area to rewet it. (2) Irr. operating hours per week Hours to rewet an area = Number of sprinkler sections. (3) Number of acres to be irr. Number of sprinkler sections = Number of acres to be irrigated at one time. Combining equations 1 and 2: (4) Irr. time (hrs/wk) X infiltration rate (in/hr) Evapotranspiration (in/week) = Number of sprinkler sections. Combining 1, 2, and 3. (5) Total acres x ET (in/wk)_ _ _ _ _ _ _ _ _ _ _ Irr. time (hrs/wk) X infiltration rate (in/hr) = Acres to be irrigated at one time. The flow required to accomplish this: (6) ET (ins/wk) x acres X 453 Irrigation time (hrs/wk) = gallons per minute required (gpm) An approximation of the HP required is given by: (7) Well dp. (ft) + av. ht. outlets + 2x op prs. (psi) X gpm 2000 = approx, static h.p. (assuming 50% efficiency) (8) Inches of water applied in a month should not be less nor greatly more than total evaporation for the month less rainfall. Inches applied in a month _ gpm pumped x hours run Acres irrigated X 453 One Final Tip Occasionally someone digs through a cluster of control lines. The following summarizes steps to repair the damage: Hydraulic 1. Join any control line to any valve line. (If system uses pres­ sure to open valves— bleed the line) 2. Turn each line on man­ ually to see which switch now operates which valves. Electrical 1. Cut power. 2. Join all ground wires. 3. Join any switch wire to any valve wire of the same wire size. 4. With power on oper­ ate switches to see which switch controls which valve. 3a. Relabel and repro­ gram the controller. or 3b. Reconnect lines at the controller so each switch controls the desired valve. 5a. Relabel and repro­ gram the controller or 5b. Reconnect lines at the controller so each switch controls the valve you want it to. SEPTEMBER, 1968 13 USGA GREEN SECTION RECORD 40 East 38th Street, New York, N. Y. 10016 TURF TWISTERS POA ANNUA CONTROL IN BERMUDA FAIRWAYS Question: I have been told Paraquat has been giving good control of Poa annua on dormant bermuda here in the South. Is this a good practice? (Georgia) Answer: If you are sure the bermuda is dormant, one quart of Paraquat per acre has given control of most weeds, Poa annua included. It would be advisable to spray a small area the first year and observe it under your growing conditions. You may find reduced rates will give good control. The spray equipment must distribute the chemical evenly or streaking will occur. Do not plan to seed immediately after spraying. GOLFER DAMAGE TO WINTER GREENS Question: Is there an effective means of determining how much damage golfers can do to greens in wet or cold weather? (Missouri) Answer: Quite a lot has been written regarding this problem and numerous talks have been given at turf conferences; the following quite well summarizes this information: 1. Do not play when the soil is saturated with water or overwet. This means that shoes actually sink through the soil or carts leave ruts. Not too often does this condition prevail. 2. This is of paramount importance: Do not walk on grass when a “white frost’’ is visible. When this is done, ice crystals in the cell vacuole will cause cell wall rupturing and death to the plant. 3. Never allow traffic on soil, especially putting greens, when all but the upper one or two inches of the soil is frozen. This can cause permanent damage to turf, as well as develop rough, bumpy putting conditions. OVERSEEDING AND PYTHIUM Question: There has been Pythium on overseeding of bermuda in the fall and again in the spring. What is the best practice for control at this time? (Florida) Answer: Pythium aphanidermatum (pythium blight) is most common on grasses used for overseeding. However, other Pythium can be present. The use of 8 to 16 ounces of 50% Captan plus an antibiotic such as Actidion at the company’s recommended rate per 1,000 square feet at seeding time has been very effective. Also, a strict weekly spray of fungicide (Thiram, Kromad, Daconil 2787, etc.) while establishing the seedlings and Dexon during Pythium outbreaks has been very effective in con­ trolling this pest. Even under close supervision, occasionally disease can develop. (Note-, use of manufacturer’s name is for illustration only and does not constitute a recommendation.)