

1ere are many insects and diseases at- 
tacking pecan trees and below we are listing 
a few of them, accompanied with the meth- 
ods of treatment as suggested by the United 
States Department of Agriculture in Farm- 
ers Bulletin No. 1829. 
NUT CASEBEARER 
Probably the most important pest at- 
tacking the pecan is the nut casebearer, 
which causes vast acreage of pecans trees 
to be stripped of nuts. The nut casebearer 
passes the winter in a tightly woven case 
attached to the joints of the bud and stem. 
In spring they attack the young shoots by 
boring into them. After about two weeks 
they change to pupae and later transform 
to brownish moths, about five-eighths of 
an inch across the wings. This moth ap- 
pears about the time the nuts begin to form, 
and proceed to lay their eggs about the ends 
of the tiny nuts. These egg's soon hatch and 
at once bore into the tiny nuts. About 26 
days are spent hollowing out the nuts. This 
explains why many of you have seen these 
tiny nuts on the ground below the tree. 
Spraying when the nuts are small, short- 
ly after the first generation eggs begin to 
hatch, is the most effective method of deal- 
ing with this insect. The recommended 
spray consists of 138 ounces nicotine sul- 
phate, 3 quarts of summer oil emulsion to 
100 gallons of water. Timing of the appli- 
cation of the spray is very important, and 
it is suggested soon after the nuts have 
formed and the tips or stigmas turn brown. 
BORERS 
Invariably run down or undernourished 
trees are always attacked by boring insects, 
the common ones being shot-hole borer and 
flat-head apple borer. There is no satisfac- 
tory control for the shot-hole borer. Preven- 
tion by keeping the trees well fertilized and 
properly cultivated. The same applies to the 
apple borer. However the grub should be 
killed in the gallery under the bark with a 
sharp knife, and the wood painted with a 
pruning compound or tree paint. The trunks 
on small trees should be wrapped with paper 
from the ground to the branches. 
PAGE TWENTY FOUR 

TWIG GIRDLER 
The twig girdler has become a serious 
pest in this area, and the only method of 
control is to gather up the broken branches 
and burn them. The girdler lays its eggs in 
the end of the broken branch, and by de- 
stroying them you prevent later infestation. 
Girdled branches hanging in the trees 
should also be burned. 
LEAF CASEBEARER 
The moth of this insect appears general- 
ly beginning in May, and lays eggs under- 
neath the leaves. The larvae hatching from 
these eggs skeletonize the leaves, causing a 
serious loss of vitality of the tree. Spraying 
with 2 pounds calcium arsenate, 8 pounds 
bordeaux mixture to 100 gallons of water, 
early in July is to be recommended. 
ROSETTE 
This is a serious disease that is prevalent 
among pecans growing on calcareous soils, 
sandy loams, loamy sand, and deep sandy 
soils deficient in organic matter. It usually 
does not attack native trees in unthinned 
pecan forests growing along Texas rivers. 
The trouble seems to start when cultivation 
begins, or rather among bred up stock. The 
Stuart, Van Deman, Frotcher, and Delmas 
are perhaps the most susceptible. 
The disease first shows up by a slight 
yellow mottling of the leaves, particularly 
in the tops of the trees. Later the leaves 
become narrowed and crinkled, with reddish 
brown areas or perforations between the 
leaves. New growth is checked, the inter- 
nodes shortened and the leaves are bunched 
together. 
Zinc sulphate is the control. Two to four 
pounds of zine sulphate to 100 gallons of 
water applied as a spray to the foliage as 
the trees begin to leaf out in the spring. 
It is important that all the leaves are thor- 
oughly wetted. Zinc sulphate can be applied 
to the soil by broadcasting evenly from the 
trunk to beyond the limb spread. On light 
soils use 14 pound for each inch of diameter 
of tree trunk. On heavy alkaline soils use 
1 to 2 pounds as above. 
