Two-Spotted Mite

Adult female twospotted spider mites may stop reproduction during the coldest winter months in production areas of colder inland valleys. Diapause is indicated by a change in color to bright orange. In coastal growing areas it is rare to have a significant proportion of the population undergo diapause. Mating and egg laying typically occur year round in all coastal strawberry-growing regions.

Twospotted spider mite and carmine spider mite damage to strawberries appears as stippling, scarring, and bronzing of the leaves and calyx. Twospotted spider mite feeding is particularly damaging during the first 2 to 5 months following transplanting in late summer or fall. Mite feeding during this critical period of plant growth substantially reduces berry number per plant and overall plantation yield. Yield loss is detectable at all mite infestation levels exceeding one mite per leaflet. Plants are less sensitive to mite feeding after initial berry set. Substantial yield loss results from15 to 20 mites per mid-tier leaflet after berry set. Plants that sustain infestations greater than 75 mites per leaflet may become severely weakened and appear stunted, dry, and turn red.