Climate

The hot weather is causing leaves to change color far ahead of schedule as trees fight to survive the heat and lack of water. (Photo by Chuck Berman)

It has been a hot summer in the Mid-Atlantic, and everywhere else.

Seventeen nations have tied or broken summer temperature records, and the humans aren't the only ones suffering.

The hot weather is causing leaves to change color far ahead of schedule as the trees in many regions fight to survive the heat and lack of water.

The stress can cause trees to produce pigments called anthocyanins, which turn the leaf red. The chemical helps leaves deal with stress and remain on the tree longer, allowing the tree to absorb nutrients.

In addition, the heat causes trees to redirect resources to its most vital parts, conserving water and energy by redirecting them to the trunk and causing the leaves to dry out and fall.

Environmental conditions that increase the water demands on a plant tend to increase the severity of leaf scorch. Hot temperatures, low humidity, high light intensity, and wind all increase the rate of water loss from the leaves, according to Marianne C. Ophardt at Washington State University cooperative.

Mild leaf scorch appears as the yellowing and then browning and drying of the tips and margins of leaves. More severe scorch appears as the yellowing and then browning of tissues between the main veins of the leaf or large angular blotches of brown tissues between the veins.

Be kind to your trees. Water them slowly and deeply.