Cracks In Trunk; Branch Crotches
Too Cold - Oriental cherry trees that are subjected to lower than normal winter temperatures may develop cracks along the trunk on the south or west side. Sometimes these cracks appear where branches meet the trunk. Ornamental cherry trees located in the east above southern New Jersey are at risk.
Leaves Yellow Then Drop
Soil Too Wet/Dry; Or Too Cold. - When leaves on an ornamental cherry tree turn yellow and begin to drop in spring or early summer, it is often because the soil is either too dry or too wet. Sometimes it is due to late cold weather. This problem can be distinguished from a disease because there is no spotting of the leaves prior to their drop. Usually affected trees develop a second set of leaves that are normal.
Plant Parts Skeletonized
Asiatic Garden Beetle - These beetles are velvety chestnut-brown. Nearly 1/2 inch long, they resemble Japanese beetles. They lay their eggs in the soil at the base of the cherry trees. Their larvae (grubs) feed on roots and the bases of young stems. They're grayish, 3/4 inch long, and curl in a C-shape like Japanese beetle grubs. Adult beetles feed at night, skeletonizing cherry foliage. They hide in the soil during the day. For more information see Controlling Asiatic Garden Beetle.
Holes In Leaves And Flowers
Japanese Beetle - Japanese Beetles converge in droves and skeletonize cherry leaves and destroy their flowers. Their grubs sometimes attack tree roots. Adults are ½-inch long, with shiny metallic green and copper-brown wing covers. Beetle larvae (grubs) are grayish-white, with dark brown heads. Fully grown grubs are plump, 3/4 to 1 inch long, and lie in the soil in a distinctive arc-shaped resting posture. For more information see Controlling Japanese Beetles.
Holes in Trunk
Peach Borer - Adult borers are wasp-like moths. They lay eggs around the base of the trunk in late summer and early fall. These hatch into white, 1 1/4-inch-long caterpillars with brownish heads. They burrow into the trunk as high as a foot above the ground or several inches below the ground. Holes in the trunk near the base of the tree from which brown frass (sawdust) and gum exude are signs that borers are at work. Young cherry trees can be killed during the first season of infestation. For more information see Controlling Borers.
Webbed Nests in Tree Branches
Tent Caterpillars - Tent caterpillars are black and hairy with white stripes and have narrow brown and yellow lines and a row of blue spots along their sides. They pests grow to be about 2 inches long in large silken nests in the forks of tree branches. They feed on tree foliage. Wild cherry trees are natural hosts for these pests. Destroy any derelict wild cherry trees in the area. For more information see Controlling Tent Caterpillars
Small Bumps On Leaves And Twigs
Scale - Scale insects form groups of small bumps or blister-like outgrowths on stems and leaves. About 1/10 inch in diameter, these waxy shells protect the insect feeding beneath. These gray bumps have a raised nipple in the center and are clustered in masses on stems where they join branches or close to growing tips. They cause leaves to turn yellow, and they often secrete honeydew, which covers leaves and encourages sooty mold. For more information see Controlling Scale
Holes in Leaves
Pear Slug - The larvae of sawflies are called pear slugs. They are a slimy, translucent olive-green worms about 1/2 inch long. Wider at the head than at the tail, they resemble a tadpole. They damage ornamental cherry trees at night, skeletonizing their leaves. They typically have 2 generations each season in the north and 3 in the south. They are mostly in the eastern United States.
Red Spots on Leaves; Holes
Leaf Spot - Leaf spot fungi cause red spots on the leaves of cherry trees that rot out, leaving holes in the foliage. Heavily infected leaves turn yellow or brown and fall prematurely. Cool, moist spring weather encourages this disease when new leaves are developing. It is rather prevalent in ornamental cherry trees. Shake out all fallen and diseased leaves from the cherry tree and destroy them. Remove all dead branches in the center of the tree to allow better aeration. Mulching helps prevent the disease from splashing up from the ground and infecting plants. For more information see the file on Controlling Fungal Disease