June 12, 2003

 

Grasshoppers Hatching in High Numbers

There have been numerous reports of grasshoppers hatching in unusually high numbers during the past two weeks according to a North Dakota State University Area Extension crop protection specialist.

"Some hot spots are being reported northwest of Kramer in Bottineau County and from Mohall to Lansford in Renville County," says Janet Knodel from the North Central Research Extension Center in Minot. "Producers should monitor their fields, especially on the edges, for young grasshoppers. Edges that have 50 to 75 young hoppers per square yard are considered threatened. In the field, that number is 30 to 45 per square yard."

The predominate species seen so far is the two-stripped grasshopper. It can be identified by its spots, stripes and color patterns. The head may be tan or green with dark spots and a light colored horizontal stripe on the segment behind the head. The femur of the large hind leg has a solid black stripe.

Grasshoppers are more easily and economically controlled while they are in the nymph stage and still within hatching sites such as roadsides and fencerows, Knodel says. "Producers will save money because fewer acres will need to be treated and the hoppers will be killed before they have an opportunity to cause significant crop loss."

Young grasshoppers are more susceptible to pesticides and early treatment prevents them from depositing eggs, which would hatch the following year.

Once egg hatch begins in or near small grain fields, infested areas should be inspected at least once a week. After two or three weeks, if populations are threatening, inspections should be conducted every other day, according to Phil Glogoza, NDSU Extension entomologist.

Glogoza has compiled a list of insecticides currently available for use against grasshoppers in crop and non-crop areas.

Field corn and sweet corn
Asana XL, Capture, Cythion, Diazinon, Mustang Max, Penncap-M, Sevin, and Warrior.

Field corn only
Dimethoate, Furadan 4F, Lorsban 4E, methyl parathion.

Soybean
Asana XL, Baythroid, Dimethoate, Furadan 4F, Lorsban 4E, Penncap-M, Scout X-Tra, Sevin, Warrior.

Sunflower
Asana XL, Baythroid, Furadan 4F, Lorsban 4E, Scout X-Tra, Sevin, Warrior.

Dry bean
Asana XL, Dimethoate, Mustang Max, Orthene 75S, Sevin.

Potato
Asana XL, Dimethoate, Penncap-M, Sevin.

Sugarbeet
Asana XL, Cythion, Diazinon, Lorsban 4E, methyl parathion, Mustang Max, Sevin.

Wheat
Cythion, Dimethoate, Furadan 4F, Malathion 57EC, Mustang Max, methyl parathion, Penncap-M, Sevin, Warrior.

Barley
Cythion, Furadan 4F, Malathion 57EC, methyl parathion, Penncap-M.

Oat
Furadan 4F, Malathion 57EC, methyl parathion, Penncap-M.

Alfalfa
Baythroid, Cythion, Dimethoate, Furadan 4F, Lorsban 4E, Malathion 57EC, methyl parathion, Mustang Max, Penncap-M, Sevin,Warrior.

Clover
Cythion, methyl parathion, Sevin.

Grass and grass hay
Cythion, Penncap-M.

Pasture and range
Cythion, Dimilin, Orthene 75S, Penncap-M, Sevin,.

Non-crop areas with grass cut for hay
Cythion, Malathion 57EC, Sevin.

Non-crop areas NOT cut for hay
Asana XL, Orthene 75S, Warrior.

Grain sorghum
Baythroid, Dimethoate, Lorsban 4E, Sevin, Warrior.

Lentils
Asana, Baythroid, Mustang Max, Sevin

Chick pea
Baythroid, Mustang Max

Proso millet, and flax
Sevin.

Canola
Capture, Warrior.

Field peas
Asana, Mustang Max, Sevin

"Always read the label and follow the recommended dosages," Glogoza says. "Also, always comply with the preharvest intervals required for each insecticide." Preharvest interval is the time interval, in days, between the last application and harvest or grazing.

Never spray a crop in bloom unless it is absolutely necessary, Glogoza recommends. If spraying a crop in bloom is necessary, spray when there will be minimal honeybee activity, preferably during the evening hours. Evening spraying also allows the insecticide to dry on the crop before bee activity resumes the next morning.

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Source: Janet Knodel, (701) 857-7682, janet.knodel@ndsu.nodak.edu
Phil Glogoza, (701) 231-7581, pglogoza@ndsuext.nodak.edu
Editor: Rich Mattern, (701) 231-6136, richard.mattern@ndsu.nodak.edu