Arborvitae
Fall needle
shed (nonpathogenic)
Inner
branchlets turn yellow then brown. Outer foliage remains healthy. Normal part
of growth cycle. No control is necessary.
Spider
mite damage
Foliage may become grey-green or yellowish. Severely affected areas may die
or become more susceptible to winter injury.
Winter injury
(nonparasitic) In spring, last year's foliage or older shoots turn brown and
die back. The browning is caused by rapid temperature changes in winter and early
spring. Plants may die if injury is to bark of lower trunk. Fertilize in spring
to stimulate growth. Remove dead wood after growth starts in spring. Plant in
protected locations.
Update6/5/09