There are three major insect pests that are just ending their current life cycle, Bagworms, and two others that are just beginning to become active, Army Worms and several grub species.
Bagworms are easily recognized by the case or bag that the larva, a caterpillar, creates and suspends from a branch. In severe infestations, the larva will find just about any suitable vertical surface on which to attach their bag, including the sides of buildings.
The bag is made from bits of plant material along with silk that the larva produces. These bags are very strong and are somewhat camouflaged from view. The larvae exit the bags in search of food and return to the bag to hide from predators.
The female never leaves the bag she created. She awaits a visit from the male, who resembles a moth. After the mating process is over, the male dies and the female will lay over 300 eggs within the bag. She will die in the late summer to early fall and the eggs overwinter within the bag. These eggs will hatch the following spring and the whole process starts again.
If you find a few bags hanging in a tree, pull them off and throw them in the garbage. If the bag is just thrown on the ground and the larva is still active, they will crawl back in to the tree and continue feeding and will build a new bag. If you find numerous bags and the larvae are still active, it is best to spray them with an insect control material. You will know if they are still active if the bag wiggles and squirms when disturbed. If none are active, wait until early summer of the next year and then spray for them.
An insect pest of many evergreens including arborvitae, junipers, pines and spruces as well as several deciduous trees like honey locust, black locust and sycamore.
Although they are popular pests in certain parts of the country, they do not spread very quickly as the female does not fly. Their spread may be from infested fire wood, ornamental plants or from “ballooning”(dispersal through strains of silk that the tiny larvae spin, that is picked up on wind currents and blown to other locations).
Amy worms are light green when they are larvae, but when they mature they turn a yellow hue or brown-green color. When they become adults they have gray-brown forewings with a white dot and gray-white hind-wings.
Army Worms lay eggs on leaves of older plants. After five to ten days caterpillars hatch from the eggs. After another ten days pass they will have grown into adults.
Army Worms are beginning their annual migration from Central America to the southern United States. They can be a serious insect pest on more than 60 plant species, including Bermudagrass.
Damage from the mass feeding of the migrating larvae begins showing up in late July to early August. There can be two or three generations of Army worms each year.
As the name implies, Army Worms move across a lawn in a mass population, feeding as they go. Entire lawns can be eaten away in just a day or two. They can often be seen “sunning themselves” on blades of grass during the day. Watch for brown areas that seem to develop overnight. The larvae will often hide in the thatch layer. If seen, apply an insect control material to the lawn.
Grubs, are the larval stage of adult beetles and are c-shaped. They vary in color since they are the beginning stages of many types of beetles and chafers.
Life Cycle and Location
Grubs will start to hatch soon, especially in the southern states. Depending upon the species, the adults have been laying eggs for several weeks and have now finished doing so.
In the northern parts of the country, the adults are still actively laying eggs. Japanese beetle adults are busy feeding on the leaves of many plants, including roses, lindens and grapes. Females choose lawns that are irrigated or have adequate water to prevent the eggs from drying out.
If you are in the south and your area is prone to grub activity, it may be too late to apply a preventative grub control treatment. You may have to use a product that will work on active grubs. If you are in the north, you are at the very tail end of applying a grub preventative. If your area is prone to grubs, get the material down soon.
If you are not sure what products to use or when to apply them, contact your Neighborhood Lawn Care Professional from Spring-Green. They can inspect your lawn and design a program that will fit the needs of your lawn.