1. General Turf Insects – Stem and Thatch Pests David J. Shetlar, Ph.D. The “BugDoc” The Ohio State University, OARDC & OSU Extension Columbus, OH © October, 2003, D.J. Shetlar, all rights reserved

2. Chewing Pests (feed on stems, clippings & leaves) Cranberry Girdler Crane Flies March Flies (borers of stems & crowns) Billbugs Annual Bluegrass Weevil Frit Fly Sucking Pests Chinch Bugs Spittlebugs Mealybugs Scales Stem & Thatch Pests

3. Cranberry Girdler (=subterranean sod webworm) Chrysoteuchia topiaria (Zeller) Notes: This pest is technically a crambid type sod webworm, but it has a very different larval behavior. The larvae tend to feed on the stems and crowns of turf, when large, rather than feeding on leaves. Infested turf tends to die in irregular patches, often at the time that white grubs would be causing similar damage. In thick turf, the dead canopy can be pulled back to reveal considerable amounts of straw colored frass pellets on the soil/thatch surface. With grubs, the entire turf canopy with the thatch can be pulled back to reveal grubs in the soil/thatch interface.

4. Cranberry girdler adults are small crambids with distinctive bands of silver scales along the wing tip. The adults tend to fly from late June through much of July. There is only one generation per year. Cranberry girdler larvae have the typical sclerotized plates that all sod webworms have, but the plates are the same color as the rest of the integument. Therefore, the typical spots are not apparent!

5. Cranberry Girdler Distribution Cranberry girdler most commonly reaches pest status in the northern part of this range. It is also a common pest in the Canadian Provinces. Damage is a perennial occurrence in Utah, Washington, Oregon, Wisconsin and Minnesota.

6. Crane Flies (=leatherjackets) European Crane Fly, Tipula paludosa (Meigen) European Marsh Crane Fly, Tipula oleracea L. Native Crane Flies, Tipula & Pedicia spp. Notes: The European and European marsh crane flies are imported pests that are well established in British Columbia, Washington and Oregon. Recent reports indicate that either or both species are also in the eastern Canadian Provinces and perhaps bordering states. Native species of crane flies can also be found infesting turf, especially turf that has been damage from snow mold or overly wet soils. The larvae are often called leatherjackets because of their tough exoskeletons, and the adults are called daddy-long-legs in Europe.

7. Adult crane flies tend to emerge in the fall or spring, depending on the species. The European crane fly emerges in September and October. The large mosquito-shaped flies often scare people, but they have non- functioning mouthparts. Eggs are usually oval and shiny black. The larvae feed on grass blades, clippings and thatch. Most crane fly larvae have gray to brown bodies with conspicuous caudal projections and a black to dark brown head capsule. Both the caudal projections and head can be withdrawn into the body when the larvae are disturbed.

8. Billbugs Annual Bluegrass Weevil Frit Fly Stem Borers

9. Billbugs Bluegrass Billbug, Sphenophorus parvulus Hunting Billbug, S. venatus vestitus Phoenician (=Phoenix) Billbug, S. phoeniciensis Chittenden Rocky Mountain (=Denver) Billbug, S. cicatristriatus Fahraeus

10. Blugrass billbug adult Hunting billbug adult Denver billbug adult Phoenician billbug adult

11. Billbug Distribution Maps Bluegrass billbugHunting billbug Phoenician billbugDenver billbug

12. Billbug damage to lawn © HDN Bluegrass billbug adult on sidewalk © HDN

13. Bluegrass Billbug Adult and larva Larva in crown, note frass filled stem.

14. The “Tug Test” To detect and confirm bluegrass billbug activity, grasp suspect stems and tug lightly. If billbug larvae have been feeding, damaged stems will break off easily. Inspect the broken stems for sawdust like frass.

15. © HDN Bluegrass Billbug Life Stages small larva mature larva fresh pupa mature pupa callow adult mature adult Most believe that billbugs have five to six larval instars. The first two or three instars are usually small enough to burrow within stems, but eventually they have to chew their way out and feed externally on crows, stems and rhizomes. When ready to pupate, the mature larva burrows into the soil and forms a compact pupal cell. The pupa is first cream colored and gradually turns a reddish brown at maturity. Newly emerged adults often have this brown color and they are called “callow adults.” Eventually, the adults turn blackish gray.

16. Bluegrass Billbug Life Cycle in Ohio

17. Notes: Bluegrass billbugs overwinter in the adult stage. The adults may hide in taller grasses nearby the turf, along sidewalks, stone walls and building foundations. Adults have also been found in thatch and old worm holes. When the soil surface temperature reaches 68ºF, the adults become active – seeking grass stems on which to feed, mating and laying eggs. Most females have mated the previous fall, but they can mate again in the spring. Females seek the thickest stems, often the seed stem, in which to excavate a hole and insert a bean shaped egg. The eggs hatch in a week or more and the small larvae burrow up and then down the stems, leaving the stems filled with sawdust like frass. By the third instar, most larvae are too large to remain within the stems. They then feed in the larger crowns or externally on the crowns, roots and rhizomes. Adults lay eggs over a long period of time. Larvae mature from mid-June to early July at which time they dig deeper into the soil to pupate. The pupal stage takes about two weeks to complete and new adults are commonly found in mid-July into August. Occasionally, summer adults will lay eggs for a partial second generation. Any larvae or pupae that haven’t finished development by the time of the first freeze appear to die. The adults are commonly seen walking about on sidewalks and driveways in September and October. Billbug control with pesticides uses one of two tactics – adult elimination before egg lay and/or larval control. Surface insecticides applied in early May usually eliminate sufficient adults to prevent damage. Larval control insecticides should be applied from mid-May into early June. Billbugs can also be easily controlled by using endophytic grasses.

18. 1999 Ohio Billbug Curative Treatment Scotts 3.2% diazinon on 28-4-6 4.00 87.5 Ortho Diazinon (5%G) 4.3658.3 Ortho Dursban (1%G)0.8716.7 Intercept H&G (0.1% deltamethrin)0.1316.7 Spectricide 3X (0.25 permethrin)0.2745.8 4.3668.8 MACH2 2LTI1.5020.8 % ControlRate appl - 11 Jun; Wooster, OH; read - 30 Jun(19DAT); 24.4 BBs/sq.ft. check 0.1020.8 VIGRO 3.34% diazinon on 28-4-6 0.2%G Bifenthrin

19. 1999 Ohio Billbug Preventive Treatment% ControlRate 0.13 1.50 0.06 0.26 0.40 0.20 DeltaGard 0.4SC 67 81 89 81 100 96 81 MACH2 2LTI Scimitar 0.88GC Meridian 25W Merit 75WP appl - 6May; Columbus, OH; read - 25June(48DAT); 32.0 adults/sq.ft. check Meridian 25W Date Appl 7 May 11 Jun 7 May 11 Jun

20. 2000 Ohio Billbug Preventive Test Treatment% ControlRate 4.36 Diazinon 3.34G 92 0.1 Talstar Fert 0.2G72 0.1 Talstar PL 0.2G 69 0.13 Tempo 0.1G 67 4.0 Diazinon 3.2G 95 appl - 16 May; Wooster, OH; read - 5July; 24.7 larvae/sq.ft. check

21. 2001 Ohio Billbug Preventive Test Treatment% ControlRate 0.2 Talstar 0.147G 64 0.272 Permethrin 0.25G32 0.087 Tempo 0.1G 50 4.0 Diazinon 3.2G 68 0.1 Talstar 0.086G 43 appl - 24 May (late preventive); Wooster, OH; read - 12July; 17.8 larvae/sq.ft. check 0.4 Merit 0.5G86 1.5 MACH2 1.5G 36

22. Annual Bluegrass Weevil Listronotus (=Hyperodes) maculicollis This weevil was included in the genus Hyperodes for many years and many still refer to this pest as the “Hyperodes weevil.”

23. Annual Bluegrass Weevil Distribution

24. H. D. Niemczyk Annual bluegrass weevil (left to right): adult, pupa, annual bluegrass stem, larva.

25. Notes: The annual bluegrass weevil is so named because it attacks annual bluegrass, Poa annua. This pest is found in northeastern North America, including most of the New England States and eastern Canadian Provinces. Its damage is most evident where Poa annua is intensively managed (e.g., golf course greens and tees, lawn bowling ranges, and lawn tennis courts). In the past, it was stated that this pest exclusively feeds on P. annua, but recent investigations indicate that the larvae will also damage bentgrass, especially when bentgrass is mixed with the P. annua. The adult weevils feed on the margins of grass leaves, causing a ragged appearance and general thinning of the turf cover. This can often be mistaken for disease. Adults overwinter in leaf litter, especially pine needle duff, surrounding managed turf. In early spring, when Forsythia first blooms to the time that flowering dogwood begins to bloom, the adults move back into the turf to feed and begin laying eggs. Females insert small bean shaped eggs into leaf sheaths and the typical weevil larvae burrow into the stems. The larvae move down to the crown and can entirely consume the crown and surrounding tillers. By early June, the first generation is completed and new adults can be seen by mid to late June. Over most of its range, a second generation is completed. The first generation is usually the most damaging one, but if there is a cool, moist summer, the second generation can cause significant damage also.

26. H. D. Niemczyk Annual bluegrass weevils commonly kill Poa annua at the time that it may normally die (the true annual forms) or go into summer dormancy.

27. H. D. Niemczyk Early damage from annual bluegrass weevils can look like disease or other malady.

28. H. D. Niemczyk Close up of annual bluegrass weevil damage to Poa annua on green.

29. H. Tashiro Annual bluegrass weevil larvae feed at the crown, causing the top portion of the plants to die.

30. Annual Bluegrass Weevil in NY Redrawn from P. Vittum & H. Tashiro, 1987 data

31. Annual Bluegrass Weevil in NY (with control windows) Severe Damage Adult Control Curative Control Redrawn from P. Vittum & H. Tashiro, 1987 data

32. Adulticide controls are usually applied from the time that Forsythia is in full bloom to the time that flowering dogwood begins to bloom. This technique uses a technique called phenological indicators – coordination of pest activity with visual cues given by various plants. Using these phenological indicators only works for the first generation. Second generation adults and larval populations have to be monitored using visual inspections of the turf.

33. ABG Weevil Management Sampling (watch for adult weevils when forsythia is in bloom) Keep Records (which tees & greens get hit and damaged?) Preventive Applications (recommended – Dursban or pyrethroid when adults move) Curative Applications (not very effective)

34. Ranked Efficacy of ABGW Insecticides (used as preventives) - 1989 – 2000 a a Data from ESA publications (1989-2000) using annual bluegrass weevil data where timing of application was stated to be “preventive.” OPs & Carb rateave Insecticidelb.ai./a.% control# tests Carbaryl8.055.62 (=Sevin) Chlorpyrifos1.053.67 (=Dursban)2.073.332 Trichlorfon8.033.57 (=Dylox, Proxol) Isofenphos2.051.27 (=Oftanol) Bendiocarb2.028.613 (=Turcam)3.078.45

35. Ranked Efficacy of ABGW Insecticides (used as preventives) - 1989 – 2000 a a Data from ESA publications (1989-2000) using annual bluegrass weevil data where timing of application was stated to be “preventive.” Pyrethroids rateave Insecticidelb.ai./a.% control# tests Deltamethrin0.0662.06 (=DeltaGard)0.1390.011 Bifenthrin0.0588.212 (=Talstar) 0.195.524 Cyfluthrin0.1487.615 (=Tempo) lam-Cyhalothrin0.0392.88 (=Scimitar) 0.06 97.38

36. Ranked Efficacy of ABGW Insecticides (used as preventives) - 1989 – 2000 a a Data from ESA publications (1989-2000) using annual bluegrass weevil data where timing of application was stated to be “preventive.” NeoNs & IGR rateave Insecticidelb.ai./a.% control# tests Halofenozide1.548.510 (=MACH2)2.041.18 Imidacloprid0.339.723 (=Merit) 0.459.77 Thiamethoxam0.2 (=Meridian) 0.26 Imidacloprid +0.3 Cyfluthrin 0.1487.412

37. Frit Fly Adult frit flies are commonly attracted to light colored surfaces like golf balls, caps, tee markers, etc. Close up of the frit fly on a grass blade.

38. Notes: There are several species of flies in the family Chloropidae that have larvae that burrow into the stems of grasses and small grain crops. This often damages the seed stems, causing the developing seeds to wither. These withered seeds are called frits, which is where the name frit fly comes from. The true frit fly, Oscinella frit (Linnaeus), is a native of Europe, but it has been spread around the world. Other chloropids may also be infesting turf. Young frit fly larvae overwinter within a grass stem. In the spring, the larvae continue to burrow down the stem, killing everything outward from where they are feeding. The affected stems first turn yellow and then brown. Up to four generation can occur during a season, and adults are most common in mid- May, late June, late July and mid-September, in Ohio. The adult flies are attracted to light colored surfaces and often alight on golf balls, thereby causing the golfer to lose concentration. Damage is often misdiagnosed as disease or drought problems. Only careful inspection of stems that are turning yellow will reveal whether the malady is being caused by frit fly maggots or some other reason.

39. Chinch Bugs Hairy CB, Blissus leucopterus hirtus Common CB, B. l. leucopterus Southern CB, B. insularis Buffalograss CB, B. occidus

40. Hairy chinch bugs in thatch Hairy chinch bug adults - long wing & short wing forms

41. Hairy Chinch Bug Damage to Lawn

42. Chinch Bug Distribution Maps Hairy chinch bugCommon chinch bug Southern chinch bug

43. Hairy Chinch Bug Life Stages egg 1st 2nd 3rd 4th 5th normal winged short winged instar nymphs adult adult

44. Hairy Chinch Bug Life Cycle in Ohio

46. Notes: The hairy, common and buffalograss chinch bugs appear to overwinter as adults. In the spring, the adults seek out suitable places to feed and lay eggs. For the hairy chinch bug, most of May is spent laying eggs and the nymphs develop from late May into early July. The later instar nymphs cause severe damage by clogging up the vascular bundles within stems and even at the crown. Damaged crowns often die. Chinch bug populations are highly regulated by rainfall and moisture. The small nymphs are susceptible to drowning in saturated thatch and all stages appear to be susceptible to the white fungus of insects, Beauveria. In normal years, a second generation is produced in late July through August. Occasionally, this second generation can be larger than the first with significant turf damage appearing in late August to mid-September. In Canada, the hairy chinch bug completes only one generation with damage being most evident in July and August. Where turf is at risk of chinch bug damage (e.g., previous experience indicates that chinch bug damage is a regular occurrence), applying controls to eliminate overwintered adults is a useful strategy. Otherwise, if visual inspection in early to mid-June and again in August reveals numerous chinch bugs and early signs of damage, curative insecticide applications are in order. Chinch bugs are rarely a problem in regularly irrigated turf or in turf containing endophytes.

47. Hairy chinch bug life cycle in Ohio with damage and control windows

48. 2001 Ohio Hairy Chinch Bug Control Treatment Merit 75WP0.39296 900.387Exp NN 830.163Tempo Ultra 980.198Talstar SC 780.481Exp NN 220.20Tempo 20WP Rate % Control appl. 30 Aug., Springboro, OH; 943.5 & 418.6 hcb/sq.ft. checks @ 7, & 14 DAT 7DAT14DAT

49. Southern chinch bugs often damage St. Augustine grass, but they can also infest bermudagrass and zoysia. In the midwestern states, the buffalograss chinch bug seems to be the most common species attacking zoysia. To the untrained eye, southern chinch bug damage often appears to be drought stress or improper irrigation distribution. The only way to tell is to look in the thatch for chinch bug nymphs and adults.

50. 2000 FL Southern Chinch Bug Control appl. 7 Sep., Boca Raton, FL; 515.1 scb/sq.ft. checks @ 6 DAT; St. Augustinegrass Treatment Talstar PL 0.2G 0.10 99 100 0.26 “ 86 0.13 “ 98 0.20 Meridian 0.33G 69 0.09 DeltaGard 0.1G 86 1.00 Dursban 1G Rate % Control 6DAT

51. Notes: There are numerous other insects that commonly inhabit the turfgrass stem and thatch zone. The twolined spittlebug is commonly found in the Gulf States where it can severely damage centipedegrass and occasionally infests bermudagrass. The nymphs make characteristic spittlemasses that can annoy anyone waking across the infested turf. The nymphs can also clog up the grass vascular system. Adult twolined spittlebugs occasionally damage ornamental plants, especially some species of holly. There are several dozen species of mealybugs and scales that infest turfgrasses. The rhodesgrass mealybug appears to be the most widely distributed, especially in low maintenance southern turf (especially bermudagrass). When well fertilized, watered and mowed, this mealybug is rarely a problem. The bermudagrass scale (an armored scale that infests bermudagrass stolons and crowns) and the European bluegrass scale (a soft scale that infests Kentucky bluegrass and perennial ryegrass) are two of the most commonly encountered scales of turfgrasses. The bermudagrass scale damage is most commonly mistaken for drought damage. The bluegrass scale produces considerable honeydew that is attractive to bees, ants and wasps. The crawlers are bright pink and can become a real annoyance when they crawl over surrounding structures.

52. Twolined spittlebugs attack centipedegrass, bermudagrass and St. Augustinegrass. Adult on St. Augustinegrass blade. Nymph pushed out of spittlemass located at base of grass stems.

53. Rhodesgrass Mealybug The mealybug nymphs settle at the bases of leaf blades and under leaf sheaths. As they mature, they develop an anal wax tube through which they excrete their honeydew. This mealybug can be found on many grasses, but is most often a problem on bermudagrass.

54. Bermudagrass Scales and Damage

55. Bluegrass Scale The bluegrass scale is of European origin. The scales look much like the lecanium soft scales that infest trees. Females produce a waxy cottony material in which they deposit their eggs. The crawlers are a bright pink color and hundreds per square foot can become a nuisance when they are crushed and stain clothing. At present, this scale is found in areas surrounding Lake Erie.