CAHNRS and WSU Extension

Wheat and Small Grains

Insect Resource Publications


Wireworms-CroppedScouting and Action Thresholds (FS059E)

Abstract: Wireworms can damage cereal grain crops, resulting in increased weed pressure and reduced stands, yields, and profits. Wireworms are the immature larval stage of click beetles, and these beetles can spend several years in this larval stage feeding on germinating seeds and young seedlings, resulting in thin crop stands and lower yields.

Identifying Wireworms (FS175E)

Abstract: Wireworms, the immature stage of the click beetle, continue to be pests of Pacific Northwest cereal crops. The insects feed on plant structures underground, causing wilt, stunting, and even death to juvenile plants. When the pests infest an area in significantly high numbers, the yields of entire fields can be lost.

Entomology Society Presentation (Esser)

How to Sample for Wireworms (Video) – Milosavljevic

Distribution of Wireworm Species (Video) – Milosavljevic

Wireworm Identification and Management (Video) – Esser

Other Pests

Cereal Leaf BeetleCereal Leaf Beetle Management (EM054E)

Abstract: The cereal leaf beetle, Oulema melanopus, (Coleoptera, Chrysomelidae), is a pest of cereal grains, grass forage/seed crops, and other grass-host species in the Pacific Northwest region. In Washington, the cereal leaf beetle has caused yield losses of 25% in spring wheat (Pike and Gould 2002).

Wheat Midge

Abstract: The wheat midge (Sitodiplosis mosellana) was found in several eastern Washington counties in 2011, with the potential to damage spring wheat crops. However, WSU scientists do not recommend that farmers apply insecticides unless they know they have an economic infestation.

Integrated Pest Management for the Wheat Head Armyworm Complex in the Pacific Northwest New

Abstract: The wheat head armyworm complex (WHAC) is comprised of two armyworm species, Dargida diffusa (Walker) and Dargida terrapictalis (Buckett), which caused recent, intermittent damage to cereal crops in the Pacific Northwest (PNW). This was the first record of D. diffusa as a pest in the PNW. While D. terrapictalis is native to the region, it has not been recorded previously as a pest. This publication covers identification, biology, and integrated pest management for WHAC. We emphasize pest monitoring and field scouting methods, and also discuss natural insecticides.

Wheat Armyworm (EM9000E)

Abstract: Armyworm caterpillars can be a troublesome pest in cereal grains grown in the Pacific Northwest states. These caterpillars, from the genus Faronta, have caused crop damage in Umatilla County, Oregon since 2007. In 2007 and 2008 the pest caused damage to crops in Lincoln County, Washington. Researchers also noted a 35% yield loss due to the insect in 2007 and 2008 in spring wheat trials conducted by Washington State University (WSU) near Davenport, Washington (Roberts 2008, 2009a, b). Bonneville County, Idaho reported damage from the pest in 2005 and 2006. 

Identification and Biology of Aphids and Cereal Leaf Beetles (Video) – Eigenbrode


Modeling Aphid Population Dynamics (REACCH)

Abstact: Under ongoing climate change, it is becoming increasingly important to understand drivers of pest insect populations in cereal grain systems. The prediction of insect population trends is a complex task and often requires a dedicated approach to data collection.

Cereal Leaf Beetle Under Projected Pacific Northwest Climates (REACCH)

Abstract: Climate change can influence the range and severity of pests, both directly as these insects respond to climatic factors, and indirectly through effects on competitors and natural enemies. This is a global issue, but one that needs to be considered as part of any climate and agricultural research for our region.

Wireworm Biology and Ecology in Washington Cereal Crops (REACCH)

Abstract: Wireworms, the subterranean larvae of click beetles, have emerged as significant pests of cereal crops. Our team has joined REACCH to address these pests, their management, and responses to climatic drivers.

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