Appendix A. Turf pest damage monitoring chart

This chart indicates when peak periods of damage are most likely to occur in the case of diseases and insects, and when seed will begin to germinate in the case of weeds. It is intended for use as a guide for monitoring pest activity and for pinpointing time periods when pest damage may occur.  Please refer to the monitoring guides that follow for further information. This chart is NOT intended to indicate when applications of pesticides should be made, if at all. 

Turf pest damage monitoring chart - Weeds
Weeds Jan Feb Mar Apr may jun jul aug Sep Oct Nov Dec Comments
Weed Scouting Period         ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓   Most weeds are large enough for easy identification.
Crabgrass and other Annual Grasses         ✓ ✓ ✓ ✓           Period of peak germination.
Annual Bluegrass               ✓ ✓ ✓ ✓   Period of peak germination. May develop seed heads earlier in season if weather is favorable.
Yellow Nutsedge         ✓ ✓ ✓           Sedges have triangular, solid stems, in contrast to the round, hollow ones of grasses.
Winter Annual Broadleaves                  ✓ ✓ ✓ ✓   Period of peak germination. 
Summer Annual Broadleaves       ✓ ✓ ✓      ✓ ✓ ✓     Period of peak germination.
Perennial Broadleaves          ✓ ✓ ✓   ✓ ✓       Period of peak germination.
Turf pest damage monitoring chart - Insects
insects Jan Feb Mar Apr may jun jul aug Sep Oct Nov Dec Comments
White Grubs        ✓ ✓ ✓ ✓       ✓ ✓ ✓ ✓     Turf appears to suffer drought stress. Skunks, raccoons, and crows may tear up the turf. Turf may pull up “carpet like.”
Ants        ✓ ✓ ✓ ✓ ✓ ✓       Mounds in turf. Mound activity begins in mid-April to mid-May. 
Billbugs              ✓ ✓ ✓       Areas wilt and do not respond to watering. Sawdust-like material in thatch. Turf is easily tugged loose. Adults active in late May – mid June. 
Chinchbugs             ✓ ✓         Wilted or browned areas, most severe in sunny or sandy areas. 
Cutworms             ✓ ✓ ✓         Burrows surrounded by brown patches, green frass may be present
European Cranefly        ✓ ✓ ✓             ✓ ✓ ✓   Larvae normally feed in the top inch of the soil, and can be found even in the winter months. Pupae may be seen in late Aug.-Sept., and adults emerge in September. 
Common (Marsh) Cranefly           ✓ ✓ ✓         Two generations each year, with new adults emerging in late April or early May. Second generation adults emerge in September. 
Sod Webworm       ✓ ✓     ✓ ✓ ✓         Discrete browned areas which coalesce later. Most common in sunny areas. May cause damage in late spring. 
Turf pest damage monitoring chart - Diseases
Diseases Jan Feb Mar Apr may jun jul aug Sep Oct Nov Dec Comments
Gray Snow Mold ✓ ✓ ✓ ✓                 Matted grass covered with white-gray mycelium. Small reddish, brown, or yellow sclerotia present. 
Pink Snow Mold ✓ ✓ ✓ ✓ ✓               Small orange brown to tan spots. Under humid conditions white to pink mycelium at margins. 
Leaf Spots/Blights/Melting Out       ✓ ✓ ✓ ✓ ✓ ✓ ✓     Oval or eye-shaped, dark bordered spots; dark specks (fruiting bodies) may be present in older diseased tissue. 
Rusts             ✓ ✓ ✓ ✓     Irregular pattern of bright orange, yellow, reddishbrown pustules on the grass blades. Powdery orange spores. 
Red Thread/Pink Patch       ✓ ✓ ✓ ✓ ✓ ✓ ✓     Pink-red, often gelatinous mycelium on leaves when moist. Tiny pink cotton candy-like puffs of spores. 
Dollar Spot           ✓ ✓ ✓ ✓       Straw-colored silver dollarsized spots. Leaf bands with brown or reddish-brown borders. White mycelium when wet.
Summer Patch             ✓ ✓ ✓       Circular patches or rings of straw-colored grass 6-8 inches across. Center may be green. Common in annual bluegrass. 
Brown Patch           ✓ ✓ ✓ ✓       1'-3' patches of light brown grass. Gray to white (smoke ring) mycelium at edge of patch may be present in moist conditions.
Fairy Ring       ✓ ✓ ✓ ✓ ✓ ✓ ✓     Rings or arcs up to 15' across often with outer ring of dark green grass. Mushrooms may be present in ring.