2 2 nd Y e ar No 105 PUBLISHED FIVE TIMES YEARLY FOR LAWNTHUSIASTS T . M. R ES CRABGRASS BATTLE REPORT certain mercury compounds seem more toxic to Crabgrass than to desirable grasses. Other heavy metals have been tested but so far phenyl mercuric ace- tate solutions seem the most promising. In reporting on their tests a New Jersey turf specialist indicated that mer- curies killed Crabgrass without serious injury to desirable grasses, but that two to five treatments were required and with a material of potentially poison- ous nature. Crabgrass appears to have no friends but countless acquaintances as the fol- lowing excerpts indicate. Names are not given to save these good folks from a deluge of mail. N ew E n g l a nd Speaks One of the lawns which I care for had al- ways been full of weeds. I used Weed Control and quickly got rid of the broad-leaved weeds. LA ST fall LAWN CARE readers were asked to report on their experiences with chemical Crabgrass control. Quite a few folks did, some in detail. The editors regret that all replies cannot be printed and that much of the humor and personality of the letters had to be omitted for lack of space. Crabgrass is also known as Water- grass, Fall Grass, Wire Grass and other names less polite. Some of the chemi- cals, in particular the arsenicals, have been suggested for Crabgrass control for many years, but actually only a relatively few readers have tried them. One trouble is that they are risky to have around. Two children died last year as a result of drinking concentrates of arsenical weed killers. Rhode Island State College is cred- ited with being the first to observe that Crabgrass in two-leaf stage, easily hand picked, also more vulnerable chemical control when just getting started. (Scotts Research photo.) to Reseeded and got a fine lawn. The next year it began to fill up with Crabgrass. Then I used a Crabgrass killer on it. The next year, after more fertilizer and grass seed, I had a beautiful green lawn and no Crabgrass. Burlington, Vt. F. M. P. Landscape Gardener Two of us used one of the highly touted Crabgrass killers according to directions. Both observed Crabgrass grew better where the so- lution had been applied. I ruined stretches of my lawn where the appli- cations overlapped. In many cases three containers with We have written to the manufacturers criti- cizing the many changes in directions which they have issued over the past year. In fact, I have three different application formulas. Taunton, Mass. This year I treated an experimental area with a mercury product, starting the last week in June. Although half strength application was prescribed for bent grasses, three such, five days apart were sufficient. Not one plant appeared in the area treated. The grass was slightly lightened in color, but not enough to mar the lawn. L. N. G. From your description of the two types of judge that what I con- Crabgrass, I should trolled was the small variety of Crabgrass. Hanover, N. H. I. A. This reader's success may be ex- plained in part by his geographical lo- cation. Crabgrass is not the pest in New England that it is on Long Island, Washington, D. C., or even Minne- apolis. The plants in a closely-cut put- ting green are more easily controlled than in a lawn. Moreover, the small, smooth variety of Crabgrass is easier to get rid of than the coarse, spreading large variety. C a n a d a, Too You suggested we try . . . for killing Crab- grass. Gave the lawn six applications as we had a bad dose of it. It really worked. Crab- grass died off, leaving great yellow spaces on lawn. Reseeded and now have a fine lawn. Ontario, Canada. A. McL. Lightens the Wife's W o rk My experience has been with mercuric I acetate and over started about the middle of July, on a weekly basis, except when rain prevented, until the last of August. Lately I have used the more two seasons. In 1947 recently prescribed concentration. This had a definite and at times lethal effect on some of the regular grass. In spite of last year's treatment, Crabgrass appeared this year about in usual strength. I started chemical treatments about July 1. The first seemed there were but two applications the last of July. ineffective. Due to rain the infestation so The treatment reduced my wife was able to pull the remainder. Manhasset, N. Y. R. M. B. During August I applied one of the new Crabgrass chemicals three times as per instruc- tions. I wasted my time for it seemed to have slight effect on the Crabgrass. The arsenicals did a fair job but this . .. Rochester, N. Y. G. A. H. is a dud. N ew Jersey Says Yes a nd No In 1947 . . . became available in this area. I tried it on Crabgrass. After four treatments the Crabgrass became brown and dry. These areas were then raked, fed and seeded. I cut most of the Crabgrass areas to 1 Vi inches, catching and destroying the clippings. I used the chemical again in 1948 on a small area, two applications eliminating it. Litde Falls, N. J. I. H. In August I had my lawn sprayed with three applications of . . . with varying results. In some cases the Crabgrass died off within three weeks, whereas in other it seemed to have very litde effect. locations While this varying condition may be the result of a lack of uniformity in spraying, I am inclined to believe otherwise as the sprays were applied as uniformly as possible with a pressure type sprayer. Plainfield, N. J. J. N. N. Differences A re Perplexing I used . . . last summer, the first treatment in late May—followed with three more at one week intervals, all with a garden spray. The Crabgrass was eliminated and the good grass was not harmed. Pottsville, Penna. D. J. G. For your tried one of information, I the highly advertised Crabgrass killers this sum- mer. I followed directions but found it burned out the grass. It looks like straw in various places. After six weeks, some of the old grass may be recovering. I am curious to see if this grass will continue or if I will have to reseed. Scottdale, Penna. W. J. B. I sprayed with a phenyl mercuric acetate preparation at the recommended rate two or three times with only mediocre results. NUMBER 105 then The company issued revised instruc- tions recommending that the material be used at a stronger rate. Doing so, I sprayed the lawn twice. No immediate results were appar- ent, but after three or four weeks I was pleas- antly surprised to find that most of the Crab- grass had been killed and the damage to the other grass, if any, was not noticeable. Hagerstown, Md. H. M. P. Arsenical Success It turned this summer but We have removed Crabgrass from our lawn by spraying with an arsenical. the lawn brown and dry for about two weeks. No Crabgrass came I believe there can be no permanent cure as the seeds blow from other places. My chief difficulty in using finding a perfectly calm day for its use as it is injurious to ever- greens, shrubs and Dayton, Ohio. this product R. L. W. flowers. in is My experience with chemical type killers over the two years indicates arsenic kills every- In areas of heavy thing and mercury nothing. is infestation, I think the use of an arsenical justified and gives good results. In no ease did I note any injury to the soil since I got good stands of grass when reseeding the areas sprayed. My use of the mercury solution involved quite a little work and did not produce the desired results. This may have been my fault but I did my best to follow the directions. Quincy, 111. J. R. C. flit is possible the weather following this treatment may have been too dry. in two weeks I purchased a bottle of . . . followed direc- tions, applying by sprinkling in early Septem- In three or four days, I made a second ber. application. In one week from the first appli- cation, the Crabgrass in that area was brown and it was apparently dead without any ill-effects to the other grass. T he Crabgrass is brown and dry and can be raked out of the lawn. Detroit, Mich. fl Crabgrass naturally slows up growth as the days get shorter and cooler. . very faithfully, according to directions, suggested frequency and observed rain and sprinkling also. This chemical seemed to stunt the growth of seedlings but didn't kill them. Some clusters that I watched closely appeared dead after treatment but in spite of repeated doses, the heads of seeds came out I. C. P. I used . . of what appeared to be dead stalks. Flint, Mich. F. E. 3 to smother Crabgrass. It was a very hot and ideal time to try my lot of plan heavy crepe paper that comes around nursery stock. I put the paper over the Crabgrass and weighted it down with bricks. I had a if I left it on night and day for ten days or until the Crabgrass was brown and yellow. Then I removed the paper, put it over fresh Crabgrass and proceeded to rake out the dead plants. Even I seeded anyhow. Rains came and the grass grew very well. Today, over three years later, lovely grass and not one Crabgrass I have plant in it. I not only killed growing Crab- grass but also all Crabgrass seeds. Bicknell, Ind. it were July and August, Mrs. S. L. L. Large Crabgrass beginning to take posses- sion as desirable grasses subside because of extreme heat. (Scotts Research photo.) in my I use the "squat, squint and stoop" method lawn. T he to get rid of Crabgrass smaller shoots can be hand pulled. Others are removed by gathering the cluster of stems in one hand and cutting off slightly below the surface. The dug Crabgrass plants are raked up and burned. Then I sprinkle grass seed, Scotts, of course, on any bare spots. Should any soil adhere to the roots, is a simple it matter to knock it into the cavity. Of course, it is necessary to stay on the of- fensive. Once the yard has been cleared, it is easy to "police" the lawn for stragglers. Moline, 111. H. W. G. I used . .. I could when to treat 4500 sq. ft. in June, first detect Crabgrass shoots, without apparent results. Later when the Crabgrass started to throw its seed spikes, I used it a second and third time. spreader on wheels might serve. At least, you might experiment with the idea. Montevideo, Minn. L. N. P. I could not see any results until late in the fall when other lawns showed patches of dead Crabgrass. Mine had disappeared, leaving my other grasses completely in control. Carroll, Iowa. fl" Weather seems to influence rapidity of action. E. J. K. I used two mercurials according to direc- tions. Because of a late start, the results were not as satisfactory as they otherwise would have been. I believe none of the Crabgrass treated produced any seed. About Labor Day, I was able to clear the lawn of all Crabgrass, fertilize and seed. The result is a nice smooth lawn practically free of weeds. Kansas City, Mo. A. E. M. I had wonderful success with phenyl mer- curic acetate. Two applications and the tufts of Crabgrass withered. The good grass was not affected. Milwaukee, Wis. F. H. F. Tried mercury, two applications, July 2 and 7, with a sprinkling can. At the end of the third week the Crabgrass was gone. Fond du Lac, Wis. W. E. R. I made one application of . . lawn this spring, according killer to my directions, and nearly lost the entire lawn. Farmington, N. M. J. C. . Crabgrass to Other Control M e t h o ds Just a few years ago, I decided to get rid of Crabgrass in my lawn. Simply sat down and pulled out all I saw as the seed was still green. My neighbors all around me have good crops of Crabgrass but only a stray stalk appears in my lawn. Cleveland Heights, Ohio. A. M. R. Someone suggested that dry ice be used to "burn" the lawn when the Crabgrass is very small. The good grasses will recover. The writer mentioned that perhaps some means of blowing the cold down could be devised, but it seems to me that since cold goes down naturally, a fertilizer- little hand propelled Several people have had this idea but it does not work. Temperatures below freezing will brown the Crabgrass but it soon revives. Crabgrass loves heat and has remarkable tenacity for life in the summer. Many investigators have been misled, thinking they killed Crab- grass they only changed its color and delayed growth. It's Still E x p e r i m e n t al in August when In general these letters bear out the results of hundreds of tests in the Scotts research plots. Results have been er- ratic—explained in part by the vagaries of soil, sunshine and rain, type of Crab- grass, stage of growth, timing and necessity of several repeat applications. Where Crabgrass is a very severe problem, it may be worthwhile to try chemical control, at least experimen- tally. The directions prescribed by the manufacturer should be followed care- fully, and concentrated materials kept out of the reach of children. Black Dirt bandits are out early this year. They took a New York City sur- geon for $300 and his banker too. A man in Hartford let them spread his lawn for 600 bucks! An Ohio operator made a killing around St. Louis put- ting on worthless "lawn conditioners" at $1.50 per bushel. CAUTION. Do not make deals with itinerant truckmen. Know with whom you are dealing—otherwise you may be held up to pay at the rate of a hundred dollars for two dollars' worth of fer- tilizer. See LAWN CARE NO. 97. O M S C O TT & S O NS C O. M A R Y S V I L LE - - O H IO EVERY PACKAGE OF S C O T TS LAWN CARE PRODUCTS BEARS T H IS T R A DE . MARK AND IS S E A L ED FOR YOUR P R O T E C T I ON