Other Invasive Pests & Diseases
Hemlock Woolly Adelgid
Hemlock woolly adelgid (HWA) is an invasive insect from Japan that feeds on the sap of hemlock trees. This insect feeds by inserting its straw-like mouthparts into the base of the hemlock needles and sucking the nutrient rich sap out of the shoot. The tree’s nutrients are depleted by HWA infestations, which reduces tree vigor, desiccates needles, causes buds to die and diminishes new growth. Infested trees often die within ten years.
Beech Bark Disease
Beech bark disease (BBD) is the result of a complex interaction among three non-native species, including one insect and two pathogens, that affects American beech trees. The insect is a small scale insect whose feeding causes damage to the bark and vascular tissues of the beech tree. The pathogens are fungi that use the wounds created by the insect to gain entry to the beech tree. Once infected by Neonectria, beech trees weaken and develop cankers. Cankers spread over time, leading to branch and crown dieback and eventually tree mortality.
Balsam Woolly Adelgid
Balsam woolly adelgid (BWA) is an invasive insect from central Europe that feeds on all true fir trees (Abies spp.). This insect inserts its straw-like mouthparts into the trunk or branches of trees and feeds on the nutrient rich sap. It also injects toxic saliva into the tree which causes abnormal wood formation that disrupts the flow of water and nutrients throughout the tree. Swelling in the branches can lead to branch dieback and successive years of infestation may cause tree mortality. Severe stem infestations can cause tree mortality in two to three years.
Asian Longhorned Beetle
Asian longhorned beetle (ALB) is a wood-boring insect that feeds on a wide variety of hardwood trees, such as maple, elm, birch and willow, eventually killing them. In the larval stage, this insect feeds on the nutrient rich tissues beneath the bark of tree, disrupting the flow of nutrients to the tree’s canopy, and into the heartwood of the tree, compromising the structural integrity of the wood. Multiple seasons of attack can lead to enough internal damage to cause branch dieback and tree mortality. The first signs of ALB can be observed about three years after infestation and tree mortality usually occurs within ten years.
Spotted Lanternfly
Spotted lanternfly (SLF) is an invasive insect from China that feeds on the sap of a wide variety of plants, including forest trees, such as black walnut, maple, birch, and willow, as well as important agricultural crops, such as grape, hops, apple, and cherry. To feed, this insect inserts its straw-like mouthpart through the plant’s bark, which creates wounds allowing plant diseases a point of entry. This feeding causes adults and immatures to produce large amounts of a sugary substance called honeydew which coats surfaces below them. Black sooty mold can grow on the honeydew, potentially affecting the plant’s appearance and health. Large numbers of SLF feeding can lead to plant stress, reduced health, and in some cases death.
Beech Leaf Disease
Beech Leaf Disease (BLD) is a newly described disease affecting American, Chinese, European and Oriental beech trees in the United States and Canada. In 2012, the symptoms of Beech Leaf Disease were first observed by John Pogacnik of Lake Metroparks in American beech (Fagus grandifolia) trees in Lake County, Ohio. This new disease complex is associated with a newly discovered nematode, Litylenchus crenatae mccannii. The nematode causes damage to newly forming leaves inside beech tree leaf buds during the winter. After emerging in the spring, the damaged leaves lead to reduced tree vigor and can eventually lead to tree mortality.