Bad bugs: They disfigure or kill your garden plants
Most pests like to attack plants under stress when their defenses are down. Kind of like us, when our immune system is stressed we get a cold. Margaret Miley, Garden Care Specialist
Surrounds Garden Care Specialist Margaret Miley spends a fair amount time every day dealing with insect pests and the damage they do to garden plants and trees. Although there are many insects that are beneficial the garden landscape, Miley says there are almost as many that would it gobble it down to the last blade of grass if left unchecked. It’s important to know the difference between the bugs that are beneficial to your garden and those that are not.
(To read about the “good” insects, scroll to the last paragraph and click the link to “insects that are beneficial”)
The insects listed below are the ones Miley classifies as “bad” bugs: Where you see a beautiful garden. They see lunch. Each pest insect has it’s territory and unique methods of robbing the rich green of your garden–leaving it pasty yellow, corrupt brown, sooty black and covered in warts.
Borers are very bad. There are many different types that specialize in attacking particular types of trees. The adult is a winged beetle that bores a hole in the bark of the tree and lays its eggs. When they hatch, the larvae end up killing the tree by eating the cambian layer. That is the living layer right under the bark that sends nutrients and water up and down the trunk of the tree.
Japanese Beetles are easy to spot because of their jewel-like glossy green backs. They pack a double whammy because, in the grub stage, they eat the roots of lawn grass. When they emerge from the ground as beetles they will march straight to your roses if you have any. They will defoliate and destroy a rose plant in a couple of days. These are difficult to control because, even if you kill all the grubs in your yard, beetles may emerge in your neighbor’s yard and migrate over.
Scale is the most difficult insect pest to control and treat. The back of the scale insect acts as a shield that deflects sprayed pesticides (as well as insect predators). They keep their eggs underneath the scale. However, when the nymphs emerge from underneath that shield to feed on the host plant, that’s when they are vulnerable to pesticide. So the timing of pesticide treatment is tricky.
There are some new chemical treatments coming out that are systemic. That is, the material gets absorbed up into the plant. So, when the scale feed on it, it kills them. It’s expensive but more effective and safe for the beneficial insects that are not eating your plants.
There are many different types that are adapted to the particular plant they like to feed on. These three are the ones we see most frequently in our Northern Virginia and Maryland gardens:
NEEDLE SCALE looks like tiny fish scales. They feed on the needle of an evergreen plant.
OYSTER SCALE is long, brown and somewhat flat.
WAX SCALE. These look like a big drop of white wax. They have different adaptations.
Spider Mites prefer evergreen needles, but will eat pretty much anything. They especially like plants that are under drought stress. The mites are too small to see; but the damage they do is easy to see. You will observe stippling or dotting all over a leaf. The leaf color will be a lighter green or yellow. If you aren’t sure you’ve got mites there is an easy way to check: Shake the branch where you think they are and hold a sheet of paper underneath, they will sprinkle onto the paper.
Mealy Bugs latch onto indoor plants that you keep outside for the summer. They have a cottony coating on them similar to Scale. That coating deflects the pesticides as well as their enemies. One of the best methods for removing mealy bugs is to simply hand wash them off your indoor plants.
Aphids. If you have Crape Myrtles, you are going to have to deal with aphids. You will see the bark turning black. Or you will see black on the leaves. That is a sign that you have an aphid infestation.
Leaf Miners go after the Boxwood trees. They bore into the leaf tissue to lay their eggs. When the larvae hatch they suck the nutrients out of the leaf. That’s when you see the leaves start to curl or turn brown. When they reach adult stage, they emerge from the leaf as colorless flies.
Lacebug. It will trash your azaleas, rhododendrons and other shade plants if they are getting too much sun. The Lacebug attaches to the underside of leaves and sucks out the chlorophyll. You will see stippling and tiny white spots on the leaves as the lacebugs make progress. Eventually, the leaves will turn yellow.
Every climate zone has its team of insect pests
Most garden pests are specialists. They’ve adapted to a particular climate and type of tree or plant—using them for food and shelter. When choosing plants and trees for your garden, it is a good idea to understand what types of pest issues may come with the plant. It’s a simple matter of understanding your vulnerabilities and being prepared so you can keep pests from getting the upper hand. It’s also important to understand that a healthy insect population requires a balance between the insect pests and the many other insects that are beneficial to garden plants and trees.
Employing a landscape maintenance firm with garden care specialists that know what to look for and and when, is the best way to protect your garden and keep healthy. If you would like to get a health check on your garden, give our garden management division a call. We’d be glad to take a walk through your garden and give our recommendations.