Katydids

About

Large, leaf-green relatives of grasshoppers with antennae as long as or longer than their bodies. Most are harmless, but a few take single bites out of young fruit, leaving corky scars (UC IPM).

Spotting it

Damage

They chew holes in a few leaves, which hardly matters, and take one small bite out of many young fruits. The wounds heal into brown, gray or tan, slightly sunken, corky patches that grow with the fruit, and badly bitten young fruit may be misshapen or drop. The inside of the fruit is usually fine (UC IPM).

How to find it early

Katydids feed at night and hide by day, and by the time scars show they are often gone. In spring, look for wingless nymphs with black-and-white banded antennae; adults come to porch lights and are slow and easy to catch on cool mornings. Cutworms and earwigs can leave similar scars (UC IPM).

When

Nymphs in spring; adults in summer.

Life cycle

Katydids spend winter as eggs; forktailed bush katydids tuck theirs into leaf edges. In California those eggs hatch from late March through May and adults appear by midsummer, and most species have one generation a year (UC IPM).

What to do, gentlest first

Start at the top. Sprays are a last step; always read and follow the product label.

1. Usually just tolerate them Prevent

   UC IPM generally recommends no control on home fruit trees and bushes, because the scars rarely hurt eating quality and katydids are seldom plentiful.

2. Catch and crush By hand

   Pick off the few you find; they're easiest to catch on cool mornings (UC IPM).

3. Egg parasites Natural enemies

   Where natural enemies are plentiful, tiny parasites often attack katydid eggs (UC IPM).

4. Spinosad after petal fall Organic spray

   If fruit damage has been unacceptable, spray spinosad after the petals fall, while fruit is small; adding horticultural oil may help it last longer (UC IPM).

   Spinosad is toxic to bees and some helpful predators for at least several hours, so never spray plants in bloom (UC IPM). Follow the label and its pre-harvest interval.

Plants it goes after

Apricot, Blueberry, Lemon, Mandarin (satsuma, clementine, tangerine), Orange and blood orange, Peach, Pear, Plum

Pressure by region

The source found, UC IPM, covers California, where at least 74 katydid species live but few are pests. Katydids live across the country, but no source rated fruit damage elsewhere, so the other ratings are estimates.

Ratings come from extension sources where available; some are estimates, as noted above.