general turf insects – nuisance pests david j. shetlar, ph.d. the “bugdoc” the ohio state...
TRANSCRIPT
General Turf Insects – Nuisance Pests
David J. Shetlar, Ph.D.The “BugDoc”
The Ohio State University, OARDC & OSU Extension
Columbus, OH
© October, 2004, D.J. Shetlar, all rights reserved
Nuisance pests are organisms that often don’t really harm the turf, but annoy users of turfgrass (e.g., earthworm castings, ant mounds), bite or sting (e.g., fleas, ticks or bees and wasps), or just gross turf users out (e.g., millipedes, centipedes, spiders, etc.).
Other nuisance pests may damage turf in their search for food. Skunks, raccoons, armadillos, moles and birds are often digging into or poking holes in turf in their search of an insect meal.
Most nuisance pests can be ignored, but when they become a severe annoyance or they significantly damage turf, the owner or manager must make a decision as what should be done. The obvious solution to reduce animal activity is to eliminate the insects that they are foraging for. On the other hand, earthworm castings can be difficult to manage as earthworms are normally considered beneficial animals that help aerify the soil and aid in thatch decomposition!
Ground-nesting Bees & Wasps
• Most ground-nesting bees are solitary and considered beneficial pollinators. They often nest in open areas or where turf has been thinned or beaten down.
• Solitary parasitic wasps often dig burrows in the soil under turf. They bury their prey within these burrows.
• Social bees (i.e., bumble bees) and wasps (i.e., yellowjackets) are considered beneficial pollinators and predators, respectively, but most people do not like to encounter their colonies when mowing or using the surrounding turf!
• Most bees and wasps in turf will not sting unless provoked!
Cicada Killer
This wasp is often 1.5-inches long, but looks bigger! The females paralyze annual cicadas, bury them and allow their larvae to feed on the living prey!
The adult wasps often fly back and forth in front of anyone who strolls into the area of the nest, but cicada killers won’t sting unless you attempt to pick one up!
Social Bees and Wasps
Bumble bees and yellowjacket wasps often build nests in the ground. They usually start these nests in old vole burrows or other pre-existing cavity.
These social bees and wasps can be dangerous because they will often sting in mass if the nesting site is disturbed. However, in areas not frequented by people, they should be left alone!
Ants Associated with Turf
• There are dozens of ant species that live in the same soils on which turf is grown.
• Most ants are considered beneficial predators.
• A few ant species can sting, most notoriously, the southern fire ants!
• Ants in the genus Lasius commonly throw up small mounds of soil which can be a nuisance on golf greens and tees as well as high maintenance sport field areas.
Fire Ants
• Most true fire ants are tropical or semitropical pests.
• Fire ants sting, though local folks often state that they have been “bit” by the ants.
• Fire ants rarely sting unless they are trying to protect food sources (aphids, scales, etc.) or the nest is disturbed. They then may sting in mass!
• Fire ants usually build above ground mounds in which they warm their brood (eggs, larvae and pupae).
• Fire ant will rapidly move their nests if regularly disturbed.
Red Imported Fire AntThis is the most common species found in the Gulf States. Single and multiple queen colonies are found in different regions.
Red Imported Fire Ant
Fire ant workers grab the skin with their mandibles and tuck the abdomen under their body to sting.
Each person reacts differently to fire ant stings. Most have intense stinging and burning with temporary welts being raised. Other people have severe reactions and the welts turn to blisters.
Red Imported Fire Ant
• Fire ants are best managed with insect growth regulator baits. Foraging workers take these baits back to the nest where the queen and/or brood are killed.
• Slow acting insecticides can also be used in baits to do the same job (KILL THE QUEEN!)
• Area applications often perform better than single mound applications.
• The “two-step” approach uses a broadcast bait or toxin followed with treatments of any individual mounds that may remain.
Ant baits should not be used heavily on the mounds as the disturbance may force the ants to move. Let the foraging workers pick up the bait scattered over the entire area!
The “Turfgrass Ant” Problem(Lasius neoniger)
• Makes volcano-shaped mounds
The “Turfgrass Ant” Problem(Lasius neoniger)
• Makes volcano-shaped mounds
• Mounds interfere with ball roll
The “Turfgrass Ant” Problem(Lasius neoniger)
• Makes volcano-shaped mounds
• Mounds interfere with ball roll
• Mounds kill turf in 3-5 inch areas
The “Turfgrass Ant” Problem(Lasius neoniger)
• Makes volcano-shaped mounds
• Mounds interfere with ball roll
• Mounds kill turf in 3-5 inch areas
• Sand and soil dull mower blades
“Turfgrass Ant” Distribution(Lasius neoniger)
“Turfgrass Ant” BiologyLittle is known!
Drs Stanley Swier (NH), Patricia Vittum (Mass), Dan Potter (KY)
• Colonies appear to be interconnected sub-colonies.
• Feeds on fats, proteins & sugars.
• Peak summer brood – May to August.
• New reproductives released in August to September.
• Often associated with turf root aphids.
• Seems to prefer sandy soils – greens!
Root aphids are commonly cultivated by the turfgrass ant. These aphids provide a ready source of carbohydrate – honeydew.
1996 Ohio Ant Control Trial
Talstar 0.66F
Merit 75 WP
Merit 0.5G
Dursban Bait 1G
Talstar 0.2G
Dursban 6.6%
42 DAT
63
67
23
75
60
54
13
0.2
0.3
0.3
0.2
1.5
0.2
1.0
Talstar 0.66F(2X)
appl - 2May (20 May), Clyde, OH
18 DAT
100
33
0
76
19
48
33
28 DAT
94
64
15
88
64
61
48
81 DAT
14
81
90
0
62
14
0
8
76
74
11
26
39
26
116 DATRateTreatment
Scimitar 0.88GC 310.06 97 57 34 40
MACH2 2LTI 431.5 63 48 47 38
Fipronil 0.05G 490.025 63 43 98 98
Scimitar 0.88GC
200.3
0.06+
Merit 75WP 100 28 57 75
1999 Ohio Ant Control Trial79 DAT13 DAT 30 DAT 128DAT 169DATRateTreatment
appl - 27 April, Clyde, OH
Dursban Pro 41.0 66 38 2 10
Merit 0.5G 570.4 29 14 77 83
2000 Ohio Ant Control TrialTreatment
Talstar 0.2G
Merit 75 WP
Meridian 25WG
Meridian 25WG
Fipronil 0.014G
+Scimitar 0.88GC 0.06 90 9098 100 79
28DATRate
0.2
0.4
0.26
0.025
0.0125
26
60
95
22
10
Fipronil 0.014G
appl - 17May; Clyde, OH;
7DAT 14DAT 12WAT
0
98
98
63
22
87
11
60
37
22
60
36
81
12
30
21WAT
2
60
67
88
65
14.8, 13.5, 14.2, 6.4, 6.0 mounds/sq.yd.@7, 14 & 28DAT&12 & 21WAT
“Turfgrass Ant” ControlRecommendations
• For SEASON-LONG control, make applications when mounds FIRST APPEAR – (Merit, Meridian, Fipronil)
• For quick knock down – (Dursban, Talstar, DeltaGard, Scimitar, Tempo-Ultra)
• Try MaxForce Granular Insect Bait – (contains hydramethylnon = Amdro)
• Look for fipronil bait – (currently registered for fire ant control in southern states only - FireStar)
Raccoons commonly forage for white grubs in turf, but they will also look for earthworms.
Raccoons usually roll back the turf when they are feeding on white grubs. When feeding on earthworms, they mash down the turf in small areas.
Skunks are also common predators of white grubs.
Skunks tend to dig up the turf and pull out clumps when they are feeding on white grubs. They rarely roll back the turf like raccoons.
Armadillo
The nine-banded armadillo is a common insect-feeding mammal in the southern states. They commonly forage for white grubs and mole crickets.
Notes: In most states, raccoons and skunks are considered fur-bearing animals and they are often protected unless you have a permit to “harvest” them.
While trapping and shooting are effective controls for these pests, managing the insects that they are foraging for is often a better option. Keep white grub populations to less than three grubs per square foot is usually sufficient to discourage raccoon and skunks from digging.
In the southern states, armadillos can be added to the list of mammals that forage for insects in turf. Armadillos will dine on white grubs and mole crickets. They often dig deep holes when they are searching for mole crickets. Again, eliminating their favored foods is often the most efficient management technique.
Eastern ground moles feed primarily on earthworms, but they will dine on white grubs when given the chance.
Moles construct straight tunnels as a form of linear pitfall traps to capture earthworms. If an earthworm drops into the burrow, it will tend to stay there. When moles make short, irregular burrows, they are likely after insect.
Mammal Management
• Trap or Shoot?
• Skunks & Raccoons haven’t read the damage threshold charts! (3-5 grubs per sq. ft. is sufficient)
• Primary food of moles is earthworms!
• Skunks & Raccoons also feed on earthworms (especially night crawlers)
• Dogs?