Grasshopper in Gardens Is your garden an island in a sea of grasshoppers? Scott Schell & Alex Latchininsky

Twostriped grasshopper (Melanoplus bivittatus) is a frequent culprit.

Twostriped grasshopper facts Peak hatch May 15 to June 15 (extended hatch - 30 to 40 days) Eats many types of plants, prefer forbs and legumes Prolific, single egg pod holds 50 to 100 eggs Adults capable of flight and short migration Nymph to adult in 40 days (hot weather)

You need to treat the nymphs When they hatch they are the size of long grain rice

Products Available: Organic - Nosema locustae (Semaspore, Nolo bait, and other brands) Single celled grasshopper disease organism is active ingredient Has a short shelf life when applied to wheat bran Grasshopper suppression, not control Treat early and often where they hatch

Products Available Chemical – carbaryl (Sevin), malathion, some pyrethroids labeled for garden Bait (various substrates) with carbaryl are effective, reduces the amount of pesticide needed by 90% Twostriped grasshopper bait susceptible Still treat early and often where they hatch. Light sprinkles good coverage – not piles here and there.

Reversing the Research: The Search for a Repellent

Potential Grasshopper Repellents AgentIngredientClaim(s)Effect Azadirachtin neem extractinsectsrepellent Deer Guardbitrexdeernone Garlic Barrier garlic extractinsects/ghnone Hot Pepper Waxcapsaicininsectsnone Pinenealpha pineneinsects?none Ropelbitrex/thymolrodent/birdnone

Use of Neem as a Grasshopper Repellent Insufficient data to recommend any compound as a reliable repellent of grasshoppers. Only neem has demonstrated the potential for repellency in laboratory trials. Biological activity found at 0.001%, which is similar to rates attained with commercially available extracts. Requires repeat applications through season.