Last week I wrote about how plants deal with excessive heat and sun, like those scorching days we experienced not long ago.

Many garden and landscape plants in our area were able to cope fairly well, but other plants didn't. As expected, local gardeners are encountering worrisome signs of heat and drought damage. How about your plants?

-- Leaf scorch: Because of the extreme heat, many area plants experienced varying levels of drought stress. One sign of drought stress is "leaf scorch." Depending on the severity, leaf scorch appears as the browning and drying of the tips and margins of leaves. With more severe scorch, the tissues between the main veins of the leaf turn brown. When extremely severe, the entire leaf turns brown and dies. Leaf scorch indicates the leaves didn't get enough water when they needed it.

-- Leaf drop: Some plants don't develop leaf scorch when suffering from heat and drought stress. Instead, entire leaves turn bright yellow and drop from the tree. Sycamore and tulip trees respond this way.

-- Leaf sunburn: If it's just too hot and there's too much sun for certain plants, their leaves will get sunburned. The first sign is the leaves turning yellow-white. The oldest leaves, young leaves and leaves facing direct sun are most likely to show this damage. Severely sunburned tissues may turn brown and die.

I have several ornamental sweet potatoes in planters sitting on concrete on the west side of the house. The oldest leaves of these plants have turned a bleached-out yellow-white and are starting to turn brown. The plants are recovering well, but a few leaves are "goners" that need to be trimmed. I've also noticed the leaves of burning bush (Euonymous alatus) have a tendency to sunburn every summer. The leaves turn almost white. The problem is most severe where the shrubs are in high heat or where they're drought stressed. However, many of the shrubs seem to recover with cooler fall weather.

-- Sunburned bark: Less obvious is sunburn or sunscald damage on the trunks of young trees. Damage to the bark on the south or southwest sides of tree trunks is usually attributed to a problem called "southwest winter injury" that happens in severely cold, sunny weather. However, in regions like ours it also can be related to hot summer temperatures and intense sunlight.

The trees most likely to suffer from sunburned bark are young, thin-barked trees such as maple, honeylocust, ash, flowering cherry, crabapple, mountain ash, birch, cottonwood, willow and fruit.

Damage occurs to bark where the heat and the light are harshest. Bark tissues are injured, but the symptoms are less obvious than sunburned leaves. The bark first appears discolored, often turning a reddish brown. Then later in the season or by the next year the bark tissues dry out, eventually cracking or peeling. This makes the tree vulnerable to attack by wood-boring insects and wood decay organisms.

Cultural factors predispose susceptible trees to sunburned bark. Recently transplanted trees, especially nondormant ones planted in late spring or summer, are prone to the problem. Drought also increases the potential of a problem with sunburned bark.

Other problems caused by hot weather in our gardens:

-- Poor fruit set, especially on tomatoes, peppers, beans and squash.

-- Sunburn on the shoulder of peppers and tomatoes.

-- Misshapen fruit, especially tomatoes and squash.

-- Bitter cucumbers, eggplants, melons and squash.

* Marianne C. Ophardt is a horticulturist for the Washington State University Cooperative Extension Office in Benton County.