Gage County
1115 West Scott St., Beatrice NE 68310
Phone: (402) 223-1384
FAX: (402) 223-1370

News Column

Paul C Hay, Extension Educator

Diseases - Good and Bad

Who ever heard of a good disease? You might ask Dean Zimmerman of rural Pickrell. Last year we had a huge hatch of wooly bear caterpillars near DeWitt that ate the leaves off 160 acres of soybeans in three days and proceeded to do quite a bit of damage to the DeWitt area soybean crop. This year Dean's field near Zion Lutheran Church had a significant hatch of wooly bears which were nearly completed eradicated by a fungus disease before they had a chance to do much damage. I have identified at least three other locations where wooly bear hatches have been killed by the fungus. At least all this humidity has been useful for something!

On the not so good side, leaf diseases have been taking a toll on area lawns. The cooler weather coming may help to reduce some of the stress and damage. Let's look at the causes and possible treatments for bluegrass and tall fescue lawns.

The predominate disease involved in the tall fescue lawns (including turf types, dwarf fescues, and K-31) is brown patch. Brown patch is caused by a Rhizoctonia solani fungus. The leaf lesions developed by the fungus are grayish in color and long, irregularly shaped and surrounded by a brown margin. Young fescue plantings and fescue turf stressed by weather, soil conditions and management errors are most susceptible to injury by brown patch. Since there is a strong association between management practices and stress levels it would be wise to review best management practices for tall fescue lawns as part of treatment program. The Extension office has a simple outline guide which will be very helpful in doing this. What we are referring to is mowing frequency, sharp blades, mowing height, fertility program, and watering practices.

Active treatment recommendations are wetting the lawn in the 4:00 to 6:00 P.M. time- frame to cool the turf. This is to cool rather than provide water for the turf. Browning turf will have even higher turf temperatures than a green lawn. Water twice per week and apply from 3/4 to 1 inch per application. Apply a fungicide to infected areas like Daconil or Mancozeb Daily watering is likely to largely evaporate and increase versus decrease disease problems. Avoid extended wet periods on the turf. Water during dew hours in early morning so as not to extend the wet period. Apply a very light .1 to .2 pounds of nitrogen per 1000 sq. ft. of nitrogen fertilizer to help stimulate new root growth.

Bluegrass lawns have lots of summer patch and dollar spot diseases. Since there is a strong association between management practices and stress levels it would be wise to review best management practices for tall fescue lawns as part of treatment program. The Extension office has a simple outline guide which will be very helpful in doing this.

Treatment recommendations involve: cooling the turf in late afternoon by wetting the grass, applying a fungicide to infected areas like Daconil or Mancozeb, watering twice per week with 3/4 to 1 inch applied at each watering, water in early morning to overlap dew times rather than extending the wetted period, avoid fertilization until after September 1, collect clipping during the active period of the fungus attack. NO TREATMENT is recommended other than overseeding for dryland lawns of either fescue or bluegrass.

View other Gage County News Columns & News Letters: http://gage.unl.edu/news/news.htm

to Contact our Staff

Extension is a Division of the Institute of Agriculture and Natural Resources at the University of Nebraska-Lincoln cooperating with the Counties and the United States Department of Agriculture.
UNIVERSITY OF NEBRASKA-LINCOLN EXTENSION educational programs abide with the nondiscrimination policies of the University of Nebraska and United States Department of Agriculture. We assure reasonable accommodation under the Americans with Disabilities Act.