This is the third installment of a series of quarterly articles to be published by the Swanton Tree Commission. These articles are meant to be informative and educational regarding the topic of trees, tree planting, and the care of the urban forest, both public and private.
Spring: Invasive Species, Both Bugs and Plants
Spring is an active time, not only for us humans but for trees and insects too. Let’s discuss some unwanted visitors that are trying to take over our landscapes.
We all have heard about the Emerald Ash Borer (EAB). It is a tiny, shiny “Emerald City” colored bug that has decimated the ash trees in Ohio. First discovered in Ohio right here in the Toledo area, it is believed to have been transported in wood pallets coming to us from Asia through the Port of Detroit.
It spread throughout the state and has been found in every Ohio county. It has been confirmed in most states east of the Mississippi River and as far west as Colorado and Texas.
The larva feed just under the bark and girdles the tree, blocking water and nutrient flow. It’s fatal for most ash growing in the United States. Some insecticides have been developed and are successful as a preventative measure. Unfortunately, they are not practical or cost-effective for large urban tree populations or forested areas. Even though the Federal quarantine for Ohio has been lifted, it’s still a good idea to not transport firewood. That’s how the little buggers got here and is the primary vehicle that spreads other potential invasive insects and disease like gypsy moth and Asian Long Horned beetle.
A new major concern is another Asian invader, the Asian Long Horned Beetle (ALB). These 1 to 1½ inch long beetles are relatively easy to identify. They are big, black and white, and leave lots of clues in your tree. They make large, dime-sized holes in a tree trunk and push out lots of stringy sawdust onto branches and to the ground. Their favorite diet is our friend the maple, but ALB will make Swiss cheese of at least 20 different tree species.
In Ohio ALB has only been positively confirmed in Claremont County, southeast of Cincinnati. Over 80,000 infested trees have been removed in 61 square miles as part of Ohio’s ALB eradication effort. Though not yet found here, we must keep our eyes open and look for the beetle and those big holes in our trees. If you see anything suspicious contact the county Ohio State University Extension office, Ohio DNR Division of Forestry, or the Ohio Department of Agriculture immediately.
Invasives can be plants too. Tree of Heaven, autumn and Russian olive, and even the Norway Maple are considered invasive and non-desirable.
One of the surprise culprits is the Callery pear. Even though the landscape retail markets are full of this ornamental favorite and people love to plant them, they are invading and choking out other plant species in natural areas. Pears were initially developed to be sterile and non-reproductive. As more ornamental pears were introduced to market, the trees unexpectedly cross pollinated. Birds spread the seeds to other areas and the infestation started. Callery pears sprang up quickly in restored prairie areas, along roadsides, and in other sensitive ecosystems.
In our home landscape, pears are pretty in the spring, grow fast, and have an interesting fall color. However they are relatively short lived, functioning for only 30-40 years. They form poor branch structure making them highly susceptible to wind, ice, and snow damage. Ornamental pears also have the annoying habit of holding onto their leaves until late fall or early winter. Their tight branching habit and dense foliage make them frequent and messy bird roosts in our urban areas.
Though developers love ornamental pears because they are cheap and grow easily in damaged soils, they are more trouble than they’re worth and are not planted on Village tree lawns or in our parks anymore. Please visit the Brochure Bank at Village Hall for more information. Contact any Tree Commission member by calling the Village Offices at 419-826-9515. They will gladly provide you with a list of undesirable landscape plants that are discouraged within the village.
Next time: Tree Commission and the Village Master Plan.