Late winter, while plants are dormant, is the ideal time for pruning trees and shrubs.

Pruning wounds are exposed for a short time before new growth and healing begins. You can see the structure of a deciduous plant before leaves obscure it. You can more easily see egg masses. Be careful that you are removing only the bad guys.

One of the good guys is the praying mantis. In the fall, a female mantis lays up to 400 eggs in one egg mass. The adult mantises die before winter, but the eggs survive in hardened egg-like case called an ootheca.

A praying mantis has a very big appetite, so it’s fortunate that it is also an accomplished hunter. These magnificent insects help gardeners by eating moths, mosquitoes, roaches, flies and aphids in gardens.

As for the bad guys, they include:

Spotted Lanternflies -

Spotted lanternfly egg masses are visible on the bark and can be easily removed. Spotted lanternfly lay their eggs in the fall, and the first instar nymphs hatch starting in May.

The egg masses dry toward the end of winter or beginning of spring. You’ll see them as cracked, light tan or gray splotches of mud on trees.

They plant their offspring on flat surfaces, and not just tree bark. To find the eggs, search tree trunks, branches, rocks and equipment or furniture that you keep outdoors.

If you see egg masses, scrape them off, double bag them and throw them away. You can also place the eggs in alcohol or hand sanitizer to kill them. If you are not double-bagging them or putting them in alcohol or hand sanitizer, it is critical that you “pop” the eggs to kill them.

Bagworms -

Bagworm cases can be found hanging from conifers, like junipers, blue spruce and arborvitae, as well as deciduous trees and shrubs.

They overwinter as eggs inside the bag, which hangs from twigs and branches of the host plant. Each bag can contain 500 to 1,000 eggs.

Removing the bags eliminates the potential for 500 to 1,000 hungry caterpillars that could hatch in spring. Use pruning shears to clip branches or break the branch. The bags are very securely fastened with silk.

Eastern Tent Caterpillars -

Egg clusters are the overwintering stage of the eastern tent caterpillar. The egg clusters are found on branches of favorite food plants, which include cherry, crabapple, apple and other deciduous ornamental trees and shrubs.

The egg mass is up to 3/4-inch in length, encircles small twigs, is dark in color and so shiny that it appears to be varnished. Simply break or cut them off to remove 150 to 350 potential caterpillars each.

Gypsy Moths -

In winter, you’ll find egg masses attached to tree trunks, stones and siding, among other places. The caterpillars’ menu includes hundreds of species, including oak, birch, linden, hawthorn, Colorado blue spruce, hemlock and pine.

Egg masses are yellow-tan in color and covered in fine hairs. Each contains 400 to 600 black, pellet-like eggs. The egg masses are irregularly-shaped oval mounds about 1 to 1-1/2 inches in length. Scrape them off and discard them.

Black Knot -

This is a fungal disease common on many fruit and ornamental trees in the genus Prunus (flowering almond, apricot, cherry, chokecherry, peach and plum).

It is most often found on wild and cultivated cherries and plums. It causes rough, coal-black galls along the branches and trunks of infected trees.

If you can remove the galls from branches, you can slow the spread of the disease. The galls are easy to spot during winter months, and infected twigs and branches can be pruned off. Destroy the cuttings and disinfect pruners between trees.

Rose Black Spot -

This is another fungus that overwinters on fallen leaves under infected roses and as purplish-red or black spots on infected canes. Rake up and destroy the fallen leaves. Prune out the diseased canes in late winter before growth starts. Dispose of the diseased material since it can re-infect your plants if left in the yard.

“Growing Green” is contributed by Lehigh County Extension Office Staff and Master Gardeners. Information: Lehigh County Extension Office, 610-391-9840; Northampton County Extension Office, 610-813-6613.