By Brad Ball, Tree Commissioner
What makes a particular tree exceptional?
It is a question that will have as many answers as there are trees in Mount Rainier’s urban forest, but did you know that our City Code includes an entire section dedicated to it? Section 12B-4 states that anyone in the city (including you!) may nominate any tree as exceptional “because of its size, age, historic association, or ecological value.” Once a tree is nominated, the city will begin a process to evaluate and possibly declare the tree as exceptional by resolution of the Mayor and Council. This will confer special recognition and protections onto the tree to uphold its long-term health and enjoyment by all the community.
On January 14th of 2020, the Mayor and City Council voted to declare our city’s first Exceptional Tree at 3209 Shepherd Street. It is a majestic eastern hemlock located on private property, with a placard calling it to your attention. If you did not know what to look for, you might just see another tree among trees, so what makes this tree exceptional? It is lusciously evergreen and perhaps a century or more old, but the fact that it is a mature hemlock here in Maryland secures its status.
The hemlock’s native range once stretched from the Appalachian Mountains of northern Georgia to the maritime provinces of Canada, and from the shores of Delaware across the Great Lakes states. However, it is becoming increasingly difficult to find a thriving hemlock in Maryland, or for that matter anywhere outside of the highest altitudes or most northern limits of its once expansive range. We owe this sad reality to a tiny insect called the hemlock woolly adelgid. Scientists believe this deadly invader arrived on a shipment of nursery trees from Japan in the early 20th century. Producing two generations per year and hundreds of offspring per adelgid, it has spread exponentially since then, draining the sap from the hemlocks it infests and eventually killing them.
Because the adelgid is spread by wind and wildlife from one hemlock to the next, where clusters of the ancient trees once flourished, now only woody skeletons decay into the forest. Much like the coronavirus pandemic we are experiencing, the more distance between the trees, the less likely it is for the infection to spread. Fortunately for this exceptional tree, there are very few other hemlocks throughout the region. No infection has yet to reach it, allowing it to potentially grow for decades to come.
The next time you are strolling through your neighborhood, look around at the trees. Are there any that stand out to you for some reason? Do you know something special about a particular tree? If so, send us a note at the Tree Commission. Maybe that tree will be the next Exceptional Tree.