ADULT Potato leafhoppers have arrived in southern Ontario!
ADULT potato leafhoppers overwinter in the southern states, gradually migrate up from the south each spring and will feed and lay their eggs on newly expanding leaf tissue as they go. The soft, succulent growth we have this year is especially susceptible. Leafhopper NYMPHS will be hatching in 1-2 weeks and appear as tiny, flightless, yellow-green insects that move sideways, very rapidly across the leaf.
Leafhoppers (and aphids) suck plant sap from expanding foliage and cause foliage to wilt, become off-coloured, flecked and stunted. Potato leafhoppers are especially damaging because they cause foliage to become stunted and deformed, with brown-black margins (“hopper burn”).
Monitor for potato leafhopper on deciduous shade trees growing in the field and in container production (yes, even seedlings aren’t safe from PLH). We found them on Acer rubrum but they can be also found on Acer platanoides (red cultivars), Acer x freemannii and Acer saccharum as well as other shade trees such as Celtis occidentalis.
Leafhoppers adults are winged, are very mobile, tiny, pale yellow-green jumping insects that are easily disturbed when you approach infested foliage. It almost looks as though they are being flicked off of the foliage. To monitor for them, try using a sweep net over the top of the canopy or place yellow sticky cards in crop foliage and monitor for tiny green leafhopper adults.
Juvenile nursery stock is at risk of economic damage levels (stunting, foliar dieback, winter kill). Monitor populations and treat the 1st generation NYMPHS with insecticides before damage becomes economically threatening. Registered insecticides for nursery production include Tristar, Sevin XLR, Actara and Imidan.