| Solving Almond Problems | |
|---|---|
| Symptoms | Probable Causes |
| Foliage Curls; Puckers; Turns Yellow | Aphids |
| Holes in Trunk | Flatheaded Borers(see below) |
| Small Bumps On Leaves And Branches | Scale |
| Leaf Spots Run Together; Ooze | Bacterial Leaf Spot(see below) |
| Flowers And Shoots Wilt Suddenly In Spring | Fire Blight(see below) |
| Gray; Velvety Coating on Leaves | Powdery Mildew |
| Leaves Brown; Branches Wilt | Blossom Blight and Dieback(see below) |
Holes in Trunk shows there are Flatheaded Borer
Adult borers are beetles, flat looking and colored metallic brown to dull gray. They emerge in the spring and females lay eggs in crevices in the tree bark. These hatch into yellowish-white worms, which promptly burrow into the trunk at the site where the eggs were laid. If the host tree is vigorous and healthy, these burrowing worms may be drowned by the sap. Weak trees fall victim to the borers' activity as they tunnel in the trunk, producing sawdust-like material (called frass) and eventually girdling the tree. White, foamy sap leaking from cracks in the bark is a sign that borers are at work. Successive generations of borers widen tree wounds, burrowing more deeply into the heartwood of the tree.
These borers are known throughout the United States, although they are most common in the eastern and central states. Young almond trees--newly transplanted ones are particularly vulnerable--can be killed during the first season of infestation. Wrap trunks of young trees with horticultural tree wrap, available in garden centers. For more information see the file on Controlling Borers
Leaf Spots Run Together; Ooze shows there is Bacterial Leaf Spot
A bacterial leaf spot sometimes attacks almond foliage. Spots are small and blister-like, later enlarging and running together. Ruptured spots release a bacterial ooze. In serious infections, shrubs may be defoliated and die. Remove and discard affected leaves as soon as spots appear. Keep the yard free of plant debris. Disinfect garden tools by dipping them in a solution of hot water and household bleach to prevent the spread of the disease. Spray affected shrubs weekly during rainy spells with a copper-based bactericide. Control insects (such as aphids) that may transmit disease organisms. For more information see the file on Dealing With Bacterial Disease
Flowers And Shoots Wilt Suddenly In Spring, Fire Blight
This disease, caused by a bacterium, is spread by insects and rain. New shoots may wilt suddenly in late spring, turn black or brown and die. The shrub appears as though it were scorched. The dead leaves droop downward on the affected twigs. If possible, destroy any nearby diseased and neglected pear, quince and apple trees, since they may harbor the fire blight organism. Between November and March, cut off affected branches at least 3 inches below the damaged area. Discard diseased branches in the trash. Before each cut, disinfect the pruning saw or shears by dipping them in hot water and household bleach or by spritzing them with a household disinfectant such as Lysol.
Leaves Brown; Branches Wilt, Blossom Blight and Dieback
This disease attacks almond leaves, turning them brown. As it progresses, entire branches wilt. The only treatment is to promptly prune out infected twigs and branches. Trash them and disinfect pruning tools in hot water and household bleach. If this is a chronic problem use wettable sulfur in the spring prior to flowering. A second application 10 days later should discourage the disease.
