Mountain Laurels are elegant shrubs with leathery leaves and unusual flowers. However, these shrubs tend to get badly infested by pests and other conditions. If your Mountain Laurel shrubs are infected by pests and you don’t know how to repair and manage the problem, read on. Here a few facts about the offending insects and tips on how to revive your mountain laurels.
The pests that affect mountain laurels are tiny insects that can cause severe damage to the mountain laurels if not treated immediately. The different pests that infest mountain laurels are Lace Bugs, Black Vine Weevil and Mulberry Whitefly.
Lace bugs: Stephanitis pyrioides and S. rhododendri
The Lace Bug is the most common pest that affects mountain laurels. The nymphs and adults of the Rhododendron Lace Bug and azalea suck the juice from the undersides of the Mountain Laurel leaves. This infestation results in damaged leaves that look mottled or white peppered. This is seen on the upper surface of the leaves. The under surface of the leaves are also damaged, making them look brown spotted with excrement.
Repairing the mountain laurel leaves after being infested by lace bugs has to be done effectively. Use quality insecticides to wipe off the pests. You can start spraying the insecticides with repeated applications as soon as the nymphs appear on the leaves in spring. Spray insecticides again after 7 to 10 days if needed. The first spray of insecticides should be done in May, and the next in July. You can use natural predators like praying mantis, ladybugs, lacewings and assassin bugs to repair and control mountain laurels.
Mulberry Whitefly: Tetraleurodes mori.
The nymph of the Mulberry Whitefly generally covers the undersides of mountain laurel leaves. This is found in many localities. The name of this whitefly was derived from the mulberry since mulberry leaves are commonly infested by this whitefly. The Mulberry Whitefly also affects many other kinds of shrubs and trees.
You can repair the damage done to the mountain laurel leaves by using Imidacloprid, an insecticide against the infestation. However, consult an expert about the dosage requirements and precautions.
Black Vine Weevil: Otiorhynchus sulcatus.
The larva of the Black Vine Weevil affects the roots of the mountain laurel shrub in ornamental plantings and nurseries. This pest initially feeds on the smaller roots and then chews the bark of the larger roots, girdling them. The girdled Mountain Laurel first turns yellow from the top to brown, and then finally dies due to severe injury.
If your Mountain Laurel is infested by the Vine Weevil, you can repair the shrub by treating the soil with insect pathogenic nematodes that control the larvae. This is the best method to protect the Mountain Laurel shrubs for landscape plantings. The compounds which can be used against vine weevils are fluvalinate and Acephate, which can be applied before egg laying and adult feeding. The usual time for spraying these insecticides is May, June and July. Take strict safety precautions, as these compounds are fatal if you have direct contact with them.
These tips will help you revive your Mountain Laurels, making them look beautiful like before.