Trees are the backdrop to every landscape, our windows into nature. They paint a picture of our timeless history with their beauty and charm. Not only do they help create the most important element to humankind, oxygen, but they also provide us with shade, serve as shelter for wildlife, are used to make homes, furniture, paper, and more.
What is there not to love about our New Hampshire trees and shrubs? Many have been on our landscapes for generations giving us hope for spring and providing treehouses and limbs to climb. Unfortunately, like all living things, trees are susceptible to disease and illness. Many of us think our beloved lawn ornaments are safe in the winter. As they go dormant and sleep for the cold, blustery months ahead, they become out of sight, out of mind. But they still need our protection as overwintering pests begin utilizing their tree bark and branches to shelter themselves from the cold.
Who are these pesky insects, how dangerous are they to our trees, and how can we stop them? Stay tuned as we discuss the two most common overwintering pests here in New Hampshire and how you can put an end to their destruction.
An overwintering pest waits out the winter season by hiding away in a nice warm spot such as under tree bark, on branches, plant matter, or inside the trunk. While certain overwintering insects can often find their way into your home, this article focuses on two common tree pests, scale insects and tree aphids.
These sap-loving creatures love to suck on the sap of your trees and shrubs, come in many different shapes and sizes, and are often quite difficult to identify. Once infested, these pests multiply very quickly and suck the life out of trees and landscape plants with their pierce-sucking mouthparts. There are two different kinds, the soft and the armored scale. The armored scale secretes a hard shell it uses to protect itself. The soft scale protects itself through a sticky substance called honeydew that makes plant leaves and twigs look shiny and wet. Over time the honeydew causes the growth of a fungus that looks like a black, sooty mold. It can cause yellowing or wilting of leaves, stunt growth, and possible branch death.
Scale insects are flat, round, and have a hard or soft waxy coating, but their discreet look can make it hard to spot them. Therefore the symptoms to look for include:
First and foremost, keeping your trees in optimal condition and health goes a long way in fighting all pests and diseases. Utilizing a tree and shrub care program that includes fertilizer, disease, and insect control will help your trees ward off infestations.
Secondly, applying dormant oil in late fall or early spring before the leaves sprout will help protect and prevent overwintering insects such as scale. Sometimes labeled as horticultural oil, dormant oils contain an emulsifier that allows them to mix with water to ensure thorough coverage of the tree or shrub. Once applied correctly, the product suffocates any overwintering insects living on the plant.
Like scale insects, aphids also create honeydew. They, too, use their piercing mouths to suck the sap out of your trees. There are many species of aphids in New Hampshire. Many species are green, but they can be almost any color. They can become a huge pest quickly due to their rapid reproduction rate. Like scale insects, the honeydew they produce not only attracts other flies, wasps, and ants, the substance itself can cause the plant to wilt, yellow, or die. Some aphids carry viruses that also cause plant disease.
The first sign of an aphid infestation is leaves curling up, turning brown, and eventually dying off. Be sure to check the undersides of leaves because aphids love to hide there. Other symptoms that your trees have an aphid infestation include:
Small numbers of colonies can be crushed by hand or removed by pruning. A large infestation may need to be treated with insecticides. But before handling this yourself, be sure to call in a tree and shrub professional such as Alliance Landscaping because not all insecticide treatments work the same on New Hampshire trees and shrubs.
Dormant oil is also an effective method for preventing aphids; therefore including a comprehensive tree and shrub care program in your routine can help keep insects such as aphids and scale at bay.
At Alliance Landscaping, we know that your trees and shrubs play a vital role in the overall health and appeal of your New Hampshire landscape. We also have trained professionals who have the knowledge and training needed to understand our beloved trees and shrubs’ different needs. We offer a highly effective 7-Step Tree & Shrub Care Program that offers proactive protection and maintenance of your large plantings on an annual basis.
For more tips and ideas and information regarding lawn care, tree and shrub care, pest control, and landscaping, follow our monthly blog.