Idaho                                                              Aphid                                                             Flyer

Cereal Leaf Beetle-Information from Montana State University
The Cereal Leaf Beetle seems to have a good hold in the Magic Valley.  Here is some information on the insect.
Life Cycle and Description
Adults are the over wintering stage, moving into grain fields and feeding for about 10 days on small grain and grass foliage after they become active in the spring. Adults prefer spring grains to winter grains. The adults are about 1/4 inch in length with brightly colored orange-red thorax, yellow legs and metallic blue head and wing covers (A. elytra) (Adult). It is important to correctly identify the adults since other beetles, common in cropland, resemble the CLB. Eggs are laid end to end singly or in groups of 2 or 3 on the upper leaf surface near the base of the leaf. Newly laid eggs are bright yellow, darkening to orange-brown and finally to black before they hatch. Egg hatch may take from 4 to 23 days depending on temperatures (D. Egg). The larvae have a yellow body with brown head and legs. A layer of slimy, fecal material, which makes them look like a slug, protects the body. When working or walking in an infested field the slimy covering will rub off on your clothing. Although both adults and larvae cause feeding damage, the larvae are responsible for majority of the damage. They feed on the leaf surface between veins, removing all the green material down to the lower cuticle resulting in an elongated windowpane in the leaf. Severe feeding damage came give a frosted appearance to the field. The larvae have 3 pairs of legs located close to the head end of the immature insect (Larvae).  When larvae have completed their feeding they shed their slimy covering and drop to the ground, hollowing out an earthen cell for pupation (E. Cell). The pupal stage takes from 10 to 14 days to complete. When new adults emerge from pupation they feed briefly on grasses, before leaving the field and finding a suitable protected over wintering site. Adults are strong, active flyers and can move some distance.
 Economic Threshold
Boot stage is a critical point in plant development and impact of cereal leaf beetle feeding damage can be felt on both yield and grain quality. Before boot stage, the threshold is: 3 eggs and larvae or more per plant (including all the tillers present before the emergence of the flag leaf). Larvae feeding in early growth stages can have a general impact on plant vigor. When the flag leaf emerges, feeding is generally restricted to the flag leaf, which can significantly impact grain yield and quality. The threshold is decreased at the boot stage to: 1 larva or more per flag leaf.
Chemical Control
To maximize efficacy, treatment is suggested when there are 3 larvae or more per plant in tillering stages or 1 larvae per flag leaf.
For Wheat, Barley, and Oats

Funded by the University of Idaho Agricultural Experiment Stations and the Wheat & Barley Commissions.

Samples collected June 29 & July 6 , 2001