Serious damage may be caused to 
the trees in some localities by other 
leaf-feeding caterpillars, scales, aphids, 
and twig girdlers. Your county agricul- 
tural agent can recommend control 
measures for these pests. 
Walnut Lace Bug 
Description—The walnut lace bug 
is a fragile, fly-like insect one-fourth of 
an inch long with lacelike wings. It 
appears in early summer. Two or three 
generations may be hatched within a 
season. 
Damage.—Lace bugs destroy the 
food-producing capability of leaves by 
inserting their mouthparts in the un- 
dersides of leaflets and sucking out 
juices. These leaves turn gray and 
yellow, and some drop prematurely. 
The nuts are poorly filled and the tree 
itself is weakened. 
Control.—Apply insecticide spray to 
the foliage when the nuts are pea to 
marble size. If later generations ap- 
pear, repeat the spray application. 
Trees 15 to 25 feet tall may need 5 
to 10 gallons of spray apiece in each 
application. Mix a spray solution of 3 
tablespoons of 57—percent malathion 
emulsifiable concentrate with 10 gal- 
lons of water. 
Curculios 
Description—Two species of cur- 
culios commonly attack walnut trees. 
Both species are one-fourth of an inch 
long, have long curved snouts, and have 
prominent humps and ridges on their 
wing covers. 
Damage.—Beginning in June, the 
adults feed on newly formed nuts and 
also on new foliage. The females lay 
their eggs in crescent-shaped punctures 
in the nuts. These nuts drop before 
maturing. 
Control.—Apply insecticide spray to 
the foliage when the stigmas of the 
female flowers start to wither. Trees 
15 to 25 feet tall will need 5 to 10 gal- 
lons of spray apiece. For the spray, 
mix 20 level tablespoons of 50-percent 
° 
(About 8 times 
natural size.) 
The walnut lace bug. 
DDT wettable powder with 10 gallons 
of water. 
Walnut Husk Maggot 
Description.—The walnut husk mag- 
got hatches from eggs laid in the 
hulls of maturing walnuts. The adult 
fly is the same size as a house fly, but 
has dark bands on the wings and a 
rusty-yellowish body. The flies appear 
in early July in the South and in late 
July in the North. They are in the 
trees for several weeks before starting 
to lay eggs. 
Damage.—The maggots feed in the 
husks (hulls) of maturing walnuts. The 
quality of the kernels of these nuts is 
reduced, and fragments of the hulls 
cling tenaciously to the shells even after 
cleaning. 
Control—A pply _ insecticide-bait 
spray to foliage when the first flies 
are seen. Three weeks later a second 
application may be needed. Trees 15 
to 25 feet tall will need 5 to 10 gallons 
of spray apiece in each application. For 
the spray, mix 3 tablespoons of 57- 
percent malathion emulsifiable con- 
centrate and 6 level tablespoons of 
7. 
