TechNotes Tips - 05.31.01

Armyworm damage has been detected on high cut turf in the Midwestern United States, primarily in the transition zone. The armyworm normally feeds on turf during the spring when the weather has been cool and wet. Damage can be severe depending on the armyworm population.

Red thread continues to be a problem primarily on perennial ryegrass. This disease is easily identified by the red threads (stroma) protruding from the leaf blade. Increases fertility levels may reduce the severity of this disease. In cases of severe red thread a fungicide application may be necessary.

Leafminers, hawthorn and elm, are quite apparent this time of the year and can cause leaves to turn brown. Once the leaves turn, brown there is little you can do. Fortunately, new growth will mask the brown leaves. For most of the northern United States, only one generation of the hawthorn and elm leafminers occurs. For more information on this caterpillar see the web site:
http://www.hcs.ohio-state.edu:90/pmi4_pest/FMPro?-db=pmi4&-format=details.html&-lay=input&Pest=Yes&Description=hawthorn%20leafminer&Usage=Insect&-recid=32882&-find=