UNITED STATES ÇOLF ASSOCIATE" ÇREEN SECTION Southeastern Office Georgia Coastal Plain Experiment Station TIFTON, GEORGIA B. P. Southeastern Director R O B I N S ON Vol. 3« No. 2« The Damage SOUTHEASTERN TURFLETTER SOD WEBTORMS August 1956 Widespread damage to turfgrasses from deceptive small worms--sod webworms~~has occurred in the Southeast» Several golf clubs not familiar with the insect have not grown enough grass to satisfy "both golfer and worms* Even these familiar with the insect suffered some damage. Why can* t damage "be prevented? Prankly, the pest is just that. Injury is first noticed by a thinning of the grass in small irregular areas which are often mistaken for disease. Such damage results from small worms eating leaves off the grass sterns and mar occur in spots, or generally over a large area« If the insect is not controlled the turf "begins to appear thin, ragged, turns "brown in color, and does not respond normally to water and fertilization» Con- tinuous feeding of sod webworms gives the turfgrass a brown or dead looking appearance with nothing but stems observable. Damage has been noticeable on many non-irrigated fairways. Attacks of the Insect seem to increase the damage to grasses suffering from a lack of water. In fact, many Bermudagrass fairways, damaged during the drought, received increased injury from such insect attacks as sod web worms. Evidence of the Insect The presence of birds feeding on putting greens or other areas has been a sign to superintendents that an insect is active. One golf club observed small black wasp swarming around its putting greens. Within a few days the grass began to thin and turn brown. Hie club called the Green Section Office for a control method. was found that the small wasp was feeding on sod webworms which vrcvo causing the damage. Sod webworms construct small tunnels (diameter of a match stem) at thb soil surface. These are often visible. A thin ragged appearance of turfgrass, plus the flutter of small debrie attached to the web of the insect are other indications that sod webworms are present. It Since webworms are sensitive to light, they hide during the day in small tunnels or in the soil ^nd feed at night. Thus, early stages of an attack may be overlooked. The insect may be observed by examining the top inch of sod}, checking the area during nightj shading a small axe a during the day by placing boards, canvas, etc. , on the turt , and letting the webworms start feeding; thoroughly flushing an area with water, etc. The Pest Sod webworms are present each year, "but not usually in sufficient number* to casis* damage. Large numbers of the insect are thought to occur as a result of past dry mild weather, The past few years have been ideal for the buildup of large populations. The insect is the larvae (worm) of a small gray moth. About 12 species are damaging to grass in the United States. Eggs are dropped into the grass "by the moth while flying, and hatch within a few days. The young start feeding and form silken webs and tunnels, thus, Hwebwormsn. They are about 1/8 inch in diameter, 3/4 inch long when grown, and have a brown-green color. Luring an average lifetime a worm may eat 7 to 13 linear feet of grass leaves or 4 to 7 inches daily. As many as 400 sod webworms have been found per square yard of turfgrass. In Tennessee and ITorth Carolina the insect may f i r st appear in May, and in Florida it may feed most of the summer and winter. Three generations per year often occur in North Carolina, and Tennessee, while five or more may be observed in Florida. This means that turf grasses are subject to attack during the entire warm growing season. Sod webworms feed principally on Bernudagrass, but also attack St. Augustinegrase. Control The f i r st step in the control of insects is proper identification. Sod webworms and their damage can be recognized from the discussion herein. Several insecticides are effective for controlling webworms. Fornmlators are mixing insecticides with fertilizers. These are satisfactory in many cases and give control when applied several times during the warm season. The folio-ring table is given as a guide for applying a few insecticides. In addition to those listed, two pounds lead arsenate per 1,000 square feet applied in 20 gallons water gives good control. Sprays generally give better results than dusts. The new granulated materials look good. The lower rates are generally used for fairway control. Insecticide DDT Dieldrin Malathion Chlordane 50$ wettable •Dowder Rate Per Acre Emulsion containing 2 lbs, per gallon Rate uer 1,000 Square Feet Emulsion 50fo 5-10 lbs. 1-2 1/2 gal. 1 3/4 - 3 1/4 oz. 3-6 oz. 4-8 4-8 5-10 « » « » 1-2 gal. 1-2 gal. 1 1/2 - 3 oz. 1 1 / 2 -3 oz. 1-2 1/2 gal. 1 3 / 4 -3 1/4 oz. 3-6 oz. 3-6 oz. 3-6 oz. FOR UP-TO-DATE HIFOEIvISTION Attend Turf Conferences In Your Area Southwestern Louisiana Institute Turf Conference, Lafayette, La. — Sept. 12 & IS* - Fourth Annual University of Florida Turf Conference , Gainesville, Fla.—Sept. 25, 26, & 27. Southeastern Turfletter US G A G R E EN S E C T I ON Sec. 34.66, P. L. & R. U. S. POSTAGE l%c PÄSD T I F T O N, G E O R G IA Permit Nq. 46 Mr. ûé U Milwaukee Bas 20W C q ^ Í S ^^