The true armyworm and aphids are of concern in the spring. Armyworms are a problem in the state in late May and early June. Infestations of armyworms can reach high levels in some years and fields should be scouted during this time period. The consequences of the Hessian fly infestation will be evident by the presence of shorter stems, lodging and reduced yields when infestations are significant. In the fall, fall armyworms may be a problem in seedling plants.
Fall armyworms feed on the young plants and eat the plants to the ground, causing a loss of stand.
Damage of this type may occur from emergence until a bard frost or freeze eliminates the threat of armyworms. Wheat will usually recover from moderate fall armyworm damage. An infestation level of five to six worms per square foot will justify treatment. In the spring, true armyworms are a threat about the time heading starts to occur. Wheat is very attractive to the armyworm and thick, vigorously growing fields can attract high infestations.