Seedling feeding may be a problem in late seeded fields. Cutworms and armyworms. Larvae of one or more cutworm species are known to cut and consume the seedling at the soil level. Damage is often severe by the time infestation is identified. Armyworm larvae feed on foliage in midseason.
Leafhoppers feed on the plant juices.
This insect infects the plant with the aster yellow mycoplasm when feeding. The aster yellow disease is also observed on canola, sunflower and several broadleaf weeds. Aphid populations can increase rapidly and have been observed on flax. Their numbers most years are not high enough to cause economic loss. This insect, while mostly a pest of cereal grains, can occasionally be identified as the cause of reduced stand in flax.