Lygus campestris (L.) was a major contributing factor in a disastrous reduction of carrot seed yields in the district of Grand Forks, B.C., during 1947 and 1948.

Knight (1941) lists this species as “common in the northern states and Canada; Holarctic in distribution”. Of its food plants he reports: “Poison hemlock (Conium maculatum) and other plants of the family Umbelliferae; Illinois specimens have been collected on wild parsnip (Pastinaca sativa) and cow parsnip (Heracleum lanatum). Reported in Massachusetts and New Brunswick as a pest on celery plants”.