Although they are
not encountered as frequently as water stress or aeration
deficit, this disorder is not uncommon and should not be overlooked.
Sunburn is injury to above ground plant parts (leaves, bark,
flowers, and fruit) caused by excessive exposure to solar
radiation. Injury results when tissue becomes dehydrated.
Similar to what we experience at the beach, pool or working
in the yard.
Sunburn may cause leaf discoloration and necrosis. The epidermis
may appear glazed, turning a silver or reddish-brown color.
Sunburned bark initially appears discolored (often a reddish-brown)
and then becomes dry. Cracking and peeling is typical, and
damage is usually most severe on the south or southwest side
of branches and trunks.
Although sunburn is most common in summer, it can occur at
any time of year, even in winter. Injury is most severe during
periods of high temperatures. Plants that tolerate full sun
conditions may be damaged when temperatures reach a critical
level. Tree trunks in closely spaced container nursery rows
are frequently shaded, when planted sun-exposed bark is prone
to sunburn. Trees that have been excessively pruned
have no leaves. These leaves have protected the trunk and
limb wood for many years. Loss of this protection can cause
severe damage and/or death, sometimes it occurs immediately
or it can take a period of years.
Deciduous trees may sustain sunburn injury during the winter
months. When branches previously protected by leaves are exposed
to direct sun, bark tissues may be sunburned. Similarly, when
branches or trees shading other trees are removed, sunburn
may result. This can be particularly severe on young trees,
thin barked species, and water stressed trees.
Santa Ynez Valley
Tree has provided you with an opportunity to make an educated
decision about tree CARE. Take a few minutes and browse our
web site. In a short time you, like us at SYV Tree will know
the destructive power of greed and ignorance. Call us. We
know what your tree needs!