Wasps about 1/8" long arrive at grapes in late April and continue
activity through May. Eggs are laid in the developing seed during
thi; period. Wasps complete their development to adult within
the seed. Adults bore out through seeds, pulp, and skin just
before grapes ripen, thereby ruining any infested grapes.
Complete crop loss is possible.

Malathion once weekly from the last of April through May (5
applications) gave good control experimentally in a location
where seed chalcids were damaging. Preventive spraying is
-r.commended because the wasps are hard to detect visually during
the egg laying period.

 Grape Root Borer

The grape root borer is the larval form of a wasp-like moth.
Larvae tunnel into the larger roots and crown below the surface
of the soil. Vines show a general decline in vigor and may be
killed. Life history and control methods have not been worked
o~ut in Florida. Control is usually considered difficult.

 Insecticides For Grape Insects

 Amount per Days before Insects
Spray material gallon harvest1 controlled

Malathion 50-57% EC2 1 1/2 t4 3 Malathion
Malathion 25% WP3 4 T 3 aphids
Se:-ln 50% WP 2 T 0 scale insects
Sevin 80% WP 4 t 0 Sevin
Sevin 23-25% flowable 4 t 0 leafhoppers
 fruit beetles
 and wasps
 Malathion or Sevin
 caterpillars
 flea beetles


] Minimum number of days between last application of the pesticide
 and harvest.
 EC = emulsifiable concentrate.
 'h? = wettable powder.
 4 t = teaspoon, T = tablespoon.



19Y7 Leafhopper Control Test (W. C. Adlerz)

Pur2ose: Comparison of times and frequencies of Sevin application
to control grape leafhoppers.

Procedure: Treatments were applied to 4-plant plots replicated
? times. The treatment schedule is listed in the table below.
Treatments were applied in 100 gallons of water per acre using
a Solo Mistblower Model 410.