Snowy tree cricket (Oecanthus fultoni)
Pest description and crop damage This tree cricket is very common in hazelnut orchards. The male produces the classic chirp that is often used in movie soundtracks, and the frequency of chirps is related to the ambient temperature. This pale green cricket carries its wings in a flattened position over the slender body. The hind legs are adapted for jumping and are elongated. The antennae are very long, surpassing the length of the body, which is approximately 0.75 inch for adults. Antennae have dark ovular markings on first and second antennal segments. The head has orange markings. Nymphs look like adults but lack wings. Tree crickets are more common in unsprayed and organic orchards. Tree crickets are omnivorous, and most of the feeding is on leaves and is inconsequential, but they also eat aphids (a beneficial effect) and they can damage nuts. Nut attacks typically leave a round divot or "scoop" in the shell from feeding. Because the mandibles or jaws are relatively weak, it is likely that nut attacks occur while the shells are still green and somewhat fleshy. Sometimes the tree cricket is able to chew through the shell and the kernel is consumed, leaving a jagged hole and empty shell. Adult females also oviposit (lay eggs) in the bark of smaller gauge hazelnut branches (3 inches in diameter or smaller). This is not economic damage, but it can leave scars that are easily confused with eastern filbert blight stromata. Each scar/hole contains a single egg, which resembles a grain of rice (1/8 in) and is yellowish in color. Note that female cicadas are another insect that wound hazelnut bark for insertion of eggs and this damage can also be confused with eastern filbert blight.
Biology and life history Eggs laid in the branches in fall are the overwintering stage. Nymphs emerge in late spring and develop to adults by the end of the growing season. There has been little research on this pest in hazelnuts, but it is thought there is just one generation per season.
Management-chemical control: HOME USE
- carbaryl
- zeta-cypermethrin
Management-chemical control: COMMERCIAL USE
- carbaryl (Sevin XLR Plus) at 2 to 5 quarts/A. 4F and 80S formulations are also available. PHI 14 days. REI 12 hr. Extremely toxic to aquatic invertebrates and bees.