Branch wilt—Hendersonula toruloidea
The earliest symptom of branch wilt is the yellowing and withering of leaves on small, outermost branches
during July and August. Next, all the leaves on the infected larger limbs suddenly wither, turn brown,
and dry up. These leaves remain attached to the twigs well after the other leaves have fallen. Portions
of the thin outer layer of the bark peel away, exposing a black sooty mass of fungal spores. Diseased
limbs have a gray to dark brown discoloration in the shape of a cylinder or partial cylinder extending
into the center of the wood.
Branch wilt develops only in warm temperatures. The fungus invades only through splits, frost damage,
and sunburn injury. Remove infected limbs in the fall after the leaves from healthy branches have dropped. Prune out diseased limbs, cutting back into healthy wood,
and burn them. Avoid sunburn by maintaining
vigorous trees through adequate irrigation, fertilization,
and pest control.
and withering of leaves
and peeling of bark