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AgAlerts 2001 From Griggs County
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Issue # 6, June 21, 2001
The emergence of leafy spurge flea beetles has been slow due to the cool and wet temperatures this summer. We have started collections on Tuesday, June 19th. There are beetles present but in low numbers at this point. Collections will be continuing through Friday, June 22nd, and begin again on Monday, June 25th. For dates and locations for future collections can be found on the "2001 Collection Page" or by calling the Extension office at 701-797-3312.
Downy mildew infections may appear in sunflower in the next few weeks in areas where heavy rains and saturated soils
coincide with sunflower germination and emergence. The downy mildew fungus is a "water mold" and thus is favored by recent
weather. Systemic infections by the downy mildew fungus result in stunted plants with yellowing along the main veins on the
upper leaf surface, and a downy white growth along the main veins on the lower leaf surface. After the systemically infected
plants appear, secondary spread may occur if wet weather reoccurs.
Once downy mildew is present, nothing can be done to halt development. Seed treatment with Apron used to be a very
effective means of control, until the occurrence of races resistant to this class of fungicide.
The amount of downy mildew present in any field depends on what percent of the downy mildew population in that field is
resistant to Apron seed treatment, how wet the soil was before emergence, and how long the soil was wet. Sunflower seed
generally is still treated with Apron or similar product, but the percent of the downy mildew population that is Apron resistant
varies considerably among fields, as shown by Dr. Tom Gulya, USDA sunflower pathologist. Satisfactory substitutes for Apron
seed treatment for control of downy mildew are still not available, but Dr. Gulya continues to seek alternatives. He has four
seed treatment fungicide trials on sunflower this year, located at Whapeton, Prosper, and two north of Moorhead. (Information
provided by Dr. Art Lamey)
(click on photos to enlarge)
The annual Barnes County Crop Variety Plot Tour will be held on July 12 at 4:30 pm. The plot is located east of Dazey on highway 26. Staff from the Carrington Research and Extension Center will conduct the tour. There will be a sponsored supper following the tour at the Bryn Farm. AGP of Valley City and Ag Country Farm Credit Services of Valley City are sponsoring the supper.
Armyworms are being found in eastern North Dakota and NW Minnesota. Most reports are from corn fields. Feeding in the whorl may cause growth problems and scouting for these insects is strongly recommended. Armyworms notch leaves while feeding and litter the plant with dark colored, soft frass. There has been a few reports of armyworms in small grains (mostly barley fields). Check the grassy field margins for worms. These areas may have been more attractive for egg laying. Armyworms prefer to feed at night and hide during the day in cracks or under clods in the soil. Scouting for these caterpillars is difficult. If feeding damage is seen but no caterpillars are present, examine soil around the base of the plant.
Please Contact Our Office For Additional Information
E-mail: griggs@ndsuext.nodak.edu
Go to the 2001 AgAlert Index Page