During a recent conversation about land management, an individual noted that they grew up in the 60s and that the woods look different from when they were a kid. They noted that they see invasive plants or evidence of invasive pests everywhere. During a different conservation, someone noted that they hope that their kids will know what hemlock trees look like.

While it is true that new species have been introduced in the last couple of decades, some of the most common have been around for longer and have just become more widespread or noticeable due to many factors. These include fire suppression, changes in wildlife populations, urban planning, landscaping practices, the known or unknown transportation of these species and other management practices.

Some invasive terrestrial plants such as garlic mustard were reported in the U.S. since the 1800s, but they didn’t get on the radar until they became widespread. Many invasive plants started out as ornamentals, such as buckthorn, barberry, autumn olive and more. They can now be found pretty much anywhere in our area, impacting our developed, undeveloped, and protected open space.

It is not always the planting of non-native species that is problematic. Use of monoculture or single-species plantings along streets, in parks, and in other developed spaces has changed the landscape. Many communities have an Elm Street. This is either through a lack of creativity in naming streets, or because American elms once lined countless streets. Dutch elm disease changed that. There are two known fungi that cause the disease, both moved around by bark beetles, which are more commonly attracted to stressed or injured trees. Densely planted street trees are prime candidates to be impacted by the fungi.

Anytime that there is a dense population of the same species, the risk of impact from and insect or disease infestation is high. Looking outside of our area, according to the New York City Department of Parks & Recreation, the five most common street trees throughout the city are London planetree, Honeylocust, Callery (Bradford) pear, Pin oak and Norway maple. Three of the five most common trees in New York, Norway maple, Honeylocust and Callery (Bradford) pear, are also the top three in the City of Kingston, with Pin oak being No. 13, according to a city tree inventory.

These trees are common in many communities, with Pin oak being the only one in its native range. Norway maple is now regulated by New York State. Callery pear may soon be as well, since it has been added to regulated and banned lists in several states, including Pennsylvania.

A disease or infestation of one or multiple of these of these species would be devastating to street tree populations, but a disease affecting Pin oaks has the potential to be worse. Oak wilt is unfortunately a real threat to our region. Like Dutch Elm Disease, Oak Wilt is caused by fungus that can be transmitted by bark beetles and through connected roots systems (root grafts). The fungus disrupts the movement of water within the tree ultimately killing the tree. As the name suggests, the disease affects oak trees. Red oaks such as northern red oak, pin oak and black oak have been documented to be more susceptible and can die within a few weeks to six months after infestation. Signs and symptoms include brown coloration developing on the outer edge of leaves and progressing inward, branch dieback, wilting leaves in spring and summer, and fungal spore mats under the bark after the tree dies.

The more potentially devastating invasive species are those that are not species or group specific. An insect that has been in the U.S. since 1869 appears poised to have a high population year this year. Based on the population last year and our mild winter, spongy moth caterpillars will be emerging soon. In addition to the spongy moths, spotted lanternfly has been detected locally with adults present last year and egg masses seen in the last couple of months. They could be right on the heels of the spongy moth caterpillars.

Awareness and detection are key to staying on top of these invasions and their impacts. The popular oriental today could be the next prolific invasive. With how interconnected regional landscapes are, if a species is an issue in one state, it could only be a matter of time before it is on our doorstep.

There are many great resources available to learn more about these and other threats to our forests, shade trees and agriculture, including the New York State Department of Environmental Conservation, New York State Parks, neighboring state agencies, Corporative Extensions, States Forest Service, United States Food and Drug administration and many more.