Parson, Kansas —
Soybean farmers should watch for spider mites as this warm, dry stretch of weather continues. In fact, several fields throughout Kansas have been treated for spider mites recently, according to a Kansas State University entomologist.
"Spider mites are usually a problem in soybeans when the weather turns warmer and drier, and plants are experiencing drought stress," said Jeff Whitworth, entomologist with Kansas State University Research and Extension.
Whitworth said the spider mites typically feed on the underside of the leaves, creating a webbing that is often in the middle part of the crop canopy.
The placement of the webbing makes it difficult to treat. Initially, the leaves turn yellow, then gray-green, and finally bronze. Severe infestations can cause the leaves to fall off completely.
Although areas that received rain recently are at lower risk for spider mite activity, growers in dry regions need to decide if they will treat their plants for spider mites, according to Doug Shoup, K-State Research and Extension agronomist in the Southeast Area Extension office.
"If spider mite activity is in the mid-canopy approaching the upper canopy, it might be a good idea to treat the infested areas in the field," Shoup said. "Reducing the spider mite pressure will help alleviate the stress on the soybeans over the next week to 10 days until our next chance of rain."
Variable yield reductions have been recorded, but generally 40 to 60 percent reductions are possible when fields are infested during late vegetative or early reproductive stages.
"This seems to be the growth stage (podding) of most of the beans treated thus far," Whitworth said, who advised monitoring soybean fields after treatment as spider mites are difficult to control, noting that spider mite populations can quickly increase within a matter of days.
Whitworth said that if growers do decide to treat for spider mites, drop nozzles can better cover the underside of the leaves and promote more effective treatment.
"It is important to get complete coverage of upper and lower leaf surfaces and even then sometimes mite populations may recover quite rapidly after treatment," he said.
A list of insecticides registered for control of spider mites is available at local K-State Research and Extension offices or at the entomology Website at www.entomology.ksu.edu/extension/.
Crops
Spider mites moving into Kansas soybeans
- Crops
-
-
Dealing with soybean seedling diseases
Soybean seedling diseases can and do occur every year in Missouri. The likelihood of these diseases showing up in fields increases when temperatures are moderate and soils are saturated at planting time.
-
Crop operating expenses up in ‘12
The cost of growing crops in Arkansas this year has risen 4.5 percent to 6.5 percent over last year, depending crop, according to research by the University of Arkansas System Division of Agriculture.
-
Spotted knapweed thriving in Missouri
It has been 10 years since spotted knapweed was first identified in southwest Missouri. The first three or four years after being noticed it didn’t seem to be spreading But in the past few years, this noxious weed has shown up in increasing amounts in new places around southwest Missouri.
-
Dry conditions add to wheat stress in western, central Kan.
Wheat is under stress in much of western Kansas south of I-70 and west of Pratt and Great Bend. Wheat fields could use at least one last good rain before harvest.
-
Report says markets plead for soybeans
Much has happened since early March that could sway farmers to take advantage of an increasing market for soybeans and plant more of the crop. Last week USDA reproted that soybean supplies relative to use could be at their lowest since 1965 after the 2012-13 cropping year
-
Early hay cutting offers some consolation in wake of 2011 drought
The early cutting is a blessing in an area where last year’s drought turned pastures to tinder and forced many producers on scorched farms in Arkansas, Oklahoma and Texas to sell cattle they could no longer feed.
-
Armyworms on the march in SW Missouri
University of Missouri Extension agronomy specialists have been closely monitoring true armyworm activity in various crops in Missouri this year. This comes after reports of significant damage to forages and crops in northern Arkansas.
-
Researchers continue battling soybean pest
University of Missouri plant pathologist Melissa Mitchum and colleagues at Iowa State University and North Carolina State University recently received a $466,000 grant from the USDA’s National Institute of Food and Agriculture to continue their research on protecting soybeans from nematode parasites.
-
Determining the cost of hay equipment
The greening of pastures and warming temperatures have triggered ruminant livestock owners to start thinking about the upcoming haying season
-
Natural predators at work on aphids in Kansas wheat
Early April brought more than warm weather to Kansas farms. Aphid populations increased around the state due to immigration of the insects from the south and local reproduction.
- More Crops Headlines
-
Dealing with soybean seedling diseases

