Detecting harmful turf insects
Many insects are beneficial to the turf in that they aid in the decomposition
of organic matter, improve soil structure and soil aeration and some
are predators of other, morn harmful organisms. Nonetheless, many insects
present problems for the homeowner.
Detecting the presence of an insect
is the first step in good insect control. When you find the insect,
examine it closely to identify it to species.
Symptoms possible causes
A. Disruption of soil:
1. Hills, piles or structures of loose dirt on turf: ants
- Mounds up to 18" tall with no visible entrance(s)
on mound with ants emerging in mass when disturbed: fire ant
- Small mounds with rims around single central entrance holes
and presence of small (3/16") grayish-black ants: pyramid ants
- Many hills of course soil with central exit holes and
presence of large (3/8") red-brown ant with
spines on the thorax: Texas leaf cutting ant
- Flat cleared areas up to 3' in diameter made of course soil
particles with a single central exit hole and with the presence
of large (3/8") reddish-brown ants with square heads
and no spines: red harvester ant
2. Trails of raised, loose dirt through turf roughly 1/4" wide in
an "S" shaped pattern: molecrickets
3. Small piles of dirt "pellets" (1/8") scattered through thatch earth worms
4. Earthen "chimneys" with central holes: crawfish
5. Small piles of loose dirt which are associated with
exit holes green June beetle larvae
6. Round holes in soil: digger wasp nests or
cicada exit holes
Direct damage to grass causing yellowing or plant death:
1. Grass blades chewed or missing: caterpillars
-
Presence of gray-brown caterpillars up to 1" long with an
inverted cream-colored "Y" on the fronts of the head
capsules: armyworms
-
Presence of gray-brown caterpillars up to 1" long that curl
into a tight "C" position when disturbed: cutworms
-
Presence of translucent greenish caterpillars up to
in. long with black raised spots on each body
segment tropical: sod webworm
2. Yellow or dead grass:
-
Roots missing and presence of cream-colored "C" shaped grubs
with three legs on body segments behind brown head capsule: white grubs
-
No tissue removed, with presence of pinkish-orange, white and
black nymph and adult stages of bugs up to 3/16" long: chinch bugs
-
No tissue removed, but with "galls" or globular object (scales)
in the root zone: Rhodegrass scale
or ground pearls
-
No tissue removed, but with shortened internodes producing
a typical bermudagrass (stunt) mites or rosetting and tufted growth, " or "witch broom" effect;
grass may be very yellow or whitish in appearance with no
insects visible to the naked eye buffalograss (stunt): mites
