4 Invasive Species to Identify in Your Landscape

It seems like more and more invasive insects are showing up these days. Because of our global economy and changing climate, it can be easier for new species to become established in new places where they cause great destruction. Invasive species can threaten your landscapes by damaging and destroying old-growth trees, disrupting shade tree infrastructure, and disrupting crop growth.

You should be aware of the most common invasive species in and near your region and know the signs of damage to look for because early detection can save your landscapes. Here are some of the most common – and destructive – invasive species to learn about:

Spotted Lanternfly

Well known for its bright colors and inspiring alarmist headlines, the spotted lanternfly (SLF) has spread to 19 states in the US. This sapsucking insect has a wide range of host plants. It prefers tree of heaven, but will also target maple, cherry, and grape. Many common shade trees and garden plants and crops are also SLF targets.

While it rarely leads to tree mortality, a bad infestation of SLF will damage plants and cause buildup of unsightly sooty mold.

The injectable Imidacloprid product IMA-jet provides  systemic protection against spotted lanternfly for one year, and ACE-jet will offer a quick knockdown treatment if results are needed fast. Treat trees early in the season to provide protection through the summer and fall months when SLF nymphs and adults are active.

Box Tree Moth

Though only first identified in the US in 2021, box tree moth is quickly establishing itself as a serious pest, as it is in Europe and Canada. Larvae target boxwood plants, common ornamental (and non-native) evergreen shrubs used throughout large parts of the US. They defoliate the shrubs before attacking the bark, which can lead to plant death. As of February 2024, it has been identified in New York, Michigan, Ohio, and Massachusetts.

Landscapers in those regions should treat vulnerable and high-value plants with a foliar spray of AzaSol, or a bigger shrub with a sufficiently large stem can be injected with TREE-äge or ACE-jet.

Pine Beetles and woodboring insects

Several non-native species of boring pine beetle have become established in the US, including Southern Pine Beetle, Mountain Pine Beetle, and Spruce Beetle. Like other woodboring insects, these beetles disrupt the tree’s ability to feed itself by creating egg galleries and can introduce a deadly fungus into the tree.

Check stressed conifer trees, especially in regions afflicted with drought. Look for foliage dieback and pitch tubes that denote exit holes. Treat vulnerable trees with an emamectin benzoate like TREE-äge R10, and use Propizol to protect against fungal infections.

We have written extensively about other woodboring insects like emerald ash borer, which are still a species of great concern in 35 states. TREE-äge R10 remains the most effective preventative treatment for emerald ash borer.

Spongy Moth

Originally a problem confined to New England, the spongy moth (Lymantria dispar) has spread across large parts of the east coast and Midwest. The voracious larvae target the newly developing leaves of oak and other hardwood trees, and bad infestations can kill trees in a few short years through repeated defoliation. The larvae droppings can also cause a huge mess, especially in someone’s backyard.

Treating oaks and other valuable hardwood trees in infested states with TREE-äge R10 will provide up to two years of protection. Treatments can also be done in the fall to avoid extra work during the busy spring. In case of a bad infestation, ACE-jet can provide fast-acting action.

While invasive insects can cause huge problems for native trees and plants, we have tools to prevent further spread and damage. Preventative measures are always preferred, since trees treated and protected ahead of time will suffer less damage, won’t be at risk of dying off, and can help form a protective barrier against further spread of the pest.

You’ll also avoid unsightly buildup of waste from the larvae, and side effects like sooty mold or damaged branches that can be a risk to people’s safety. Injecting trees in the fall will ensure long term protection lasting into spring when the larvae are active. Reach out to your local regional technical manager to find out what the best treatment options are for you.