Crushed dolomitic limestone—which 
contains magnesium oxide—will cor- 
rect this and reduce the acidity of your 
soil. 
Your county argricultural agent can 
test the soil for its acidity and arrange 
for an analysis of its nutrient needs. 
You may also send a soil sample to 
your State agricultural experiment 
station for analysis. 
OTHER REQUIREMENTS 
Black walnut trees often need to be 
watered or otherwise cared for to grow 
well and produce large nut crops. 
Because of their deep tap roots, the 
trees are drought resistant. Keep an 
area 4 feet in diameter around each 
tree cleared of weeds and grasses that 
would compete for water and nutrients. 
Such cleared areas are not needed for 
trees planted in yards, but they should 
be watered regularly while young be- 
cause of competition with grass for 
moisture. 
The part of your tree that is below 
the graft may produce suckers, Prune 
these off at the trunk. Unless removed 
while small, the suckers may crowd out 
the shoot growing from the variety 
scion. | 
Livestock should not be allowed to 
graze around young black walnut trees. 
When the trees are 15 years old, how- 
ever, they can be interseeded with 
grasses and legumes. Animals turned 
in to pasture will not damage these 
older trees. 
HARVESTING NUTS 
Lightly colored walnut kernels have 
a milder flavor than dark ones. If you 
prefer light kernels, harvest the nuts as 
soon as they drop from the trees in the 
fall. Leaving them on the ground until 
the hulls partially decompose causes a 
discoloration of the kernels. 
The hulls are thick and fleshy at 
maturity. They can be mashed and re- 
moved by hand, but mechanical devices 
make the job easier. Vegetable peelers 
used in restaurants and hand- and 
power-operated corn shellers will re- 
move the hulls satisfactorily. 
The rear wheel of an automobile can 
be an effective hull remover. Fit one 
of the rear wheels with a tire chain 
and jack up the rear with just enough 
room beneath the tire for the nuts to 
pass. The chain will remove the hulls 
as the nuts are forced through a 
trough below the turning wheel. 
After the hulls are off, the nuts 
should be washed thoroughly and 
spread out away from direct sunlight 
to dry. Drying will take 2 or 3 weeks. 
The nuts can then be stored in a cool, 
dry place until needed. 
It is difficult to extract kernels in 
large pieces from most varieties of 
black walnut because of the thick shell 
and convolutions of the kernel. The 
nuts can be tempered by soaking them 
in water for 1 or 2 hours, then keep- 
ing them moist overnight in a closed 
container. The kernels absorb enough 
moisture to become tough, yet remain 
loose in the shell. 
DISEASES 
The most serious diseases of black 
walnut are walnut anthracnose and 
bunch disease. They attack the tree 
throughout its natural range. 
Walnut Anthracnose 
Symptoms and damage.—Walnut 
anthracnose, or leaf blotch, is a fungus 
disease that destroys leaves of black 
walnut trees. It overwinters in fallen 
leaves, and the first infection by the 
spores on new leaflets occurs from the 
middle of May until the middle of June. 
Infected leaflets develop many cir- 
cular, dark-brown spots, ranging from 
one-sixteenth to five-sixteenths of an 
inch in diameter. These often merge to 
form large dead areas with yellow 
borders. Infected leaflets usually drop 
from trees by late July or early August. 
In years of severe infection, black 
walnut trees are often entirely de- 
foliated. Many of the nuts are then 
empty or contain blackened and 
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