UC IPM Home > Homes, Gardens, Landscapes, and Turf > Fruits and Nuts > Environmental
Disorders
How to Manage Pests
Pests in Gardens and Landscapes
Frost
Frost-damaged leaves or twigs become water-soaked, wither, and turn dark brown to black. On fruit, the
rind surface may appear corroded. Watery, brownish specks or pits called icemarks may be present. The
pulp underneath the icemarks dries. A frost may kill young trees but rarely mature trees.
Solutions
Certain cultural practices, such as avoiding pruning or fertilizing during late summer and providing
protection during critical injury times, can reduce the impact of frost. Avoid oil sprays in the fall.
Protect young trees from frost damage by building a wooden framework above the tree and covering it with
a cloth. Cover with a tarp in the evening when frost is expected. Remove the tarp during the day to give
the tree light. Fiberglass insulation can also be tied around the trunk on a young tree to protect it
from freeze damage. If trees are damaged by frost, do not remove dead leaves or twigs until late spring
or summer. Prune out dead material after new growth develops. Pruning too early may remove live branches
and increase the risk of more frost damage. |
Frost-damaged
leaves
Damaged
fruit (left) and healthy fruit (right)
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