What Is Wrong With My Wild Lilac?

Are there wet, sappy areas on the bark of the main trunk, which may crack?

Is the bark rough or gnarled, trunk and branches have swellings, sap and sawdust-like frass are apparent?

Are the leaves curled and distorted, sticky to the touch?

Are the leaves yellow, and the plant looks stunted?

Do the leaves have white, cottony clusters on them?

Are the leaves covered with small bumps?

Larvae of flathead borers tunnel beneath the bark, causing wet, sappy on the bark of the main trunk. Boring may kill limbs or entire trees. Prevention is the most effective management approach for flathead borers, which typically attack trees that have been previously injured or damaged. Providing proper care and protecting landscape plants from injury will make them less attractive to the borers. Avoid pruning spring-summer while adults are active. Properly dispose of infested wood material, as beetles may emerge from logs and attack nearby plants.

Larvae of sycamore borers bore into host bark, causing rough or gnarled bark, trunk and branch swellings, sap exudation, and sawdust-like frass. Preventing attacks by providing proper cultural care is the primary management strategy for sycamore borer. If you see borer holes in your trees, you can try to probe into them with a flexible wire or inject a solution of parasitic nematodes. After treatment, seal holes with putty.

Distorted and sticky leaves and stems are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used only with severe infestations.

Yellow leaves and stunted look are caused by whiteflies. These tiny, mothlike flies and their larvae feed by sucking plant juices. Whiteflies secrete honeydew, a sugary substance that makes leaves sticky to the touch. Control whiteflies by eliminating garden weeds and by introducing green lacewings in the garden. Spray infested plants with insecticidal soap every 3 days for 2 weeks.

White, cottony clusters on leaves are caused by mealybugs. These tiny insects are covered with a fluffy white coating. They feed by sucking plants sap. They produce the sticky substance honeydew which makes leaves sticky. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

Leaves covered by small bumps are caused by scales. These tiny, shelled insects often feed on the undersides of the leaves, causing an unhealthy appearance with yellowish blotches on the upper leaf surfaces. Scrape off minor infestations with your fingernail. Prune out badly infested growth, or use a soft brush and soapy water to gently scrub the scales off the stems. Control scales by spraying insecticidal oil during the growing season.

Rabbits may feed on young Ceanothus until it has become more established. Set up protective barriers around young plants until they have become more established. Bury the bottom of the barrier at least 6-10 inches into the ground. Bending a few inches of the bottom of the fence outward will also help deter rabbits from digging beneath it. If using chicken wire, use a mesh size of less than 1 inch to keep away young rabbits.