With the wet spring we have been experiencing in the Willamette Valley so far we tend to look at our production fields and blame their appearance and lack of vigor on the weather. Upon further inspection, you may find some added stresses and common pests. One such pest showing up more often this spring is the persistant Crane Fly.
European cranefly (Tipula paludosa) and Marsh cranefly (Tipula oleracea)
The larvae of these two pest species feed on many plant species, including grasses, clovers, mint crops, root vegetables, and probably even decaying matter. As larvae mature, they come to the soil surface at night and feed above ground on crowns of grasses. They have been seen to clip stems of peppermint.
The European cranefly, (T. paludosa) , deposits eggs randomly on moist soil, grasses, clovers, and cover crops by dropping them in flight or when walking over these areas. An adult female produces 300 to 400 eggs, which hatch in 11 to 15 days. Larvae enter the soil and feed on humus, vegetable waste that is decomposing, and crowns or roots of plants through late April and early May. Young larvae tend to remain in the soil day and night and are highly resistant to cold. In spring, the larger larvae come to the soil surface at night and feed on aerial parts of plants. Larvae pupate in the soil (late June, July, early August). Adults emerge in late August and September. (Tipula paludosa)
Controls available for use in many of our seed crops include Lorsban, and Baythroid/Tombstone.
Ask your CPS fieldman to scout the areas you might consider potential problems.
Information provided by Oregon State University Extension