We don’t have any ticks at our field school in northern Maine. Traditionally, we’ve been quite a bit north of the tick line, below which they live. However, a few hours south the Maine coast is overrun with ticks. The bad news is that they are slowly moving north. The good news is that our predominant tree species is Balsam Fir, and Balsam Fir kills ticks.

According to this article in Nature, the needles and essential oils in Balsam Fir kill overwintering ticks at cold temperatures. Ticks burrow into the leaf litter on the ground as a way to survive a long, cold winter. According to the article, where that leaf litter is composed of fir needles, the ticks have a much lower survival rate. They tested it a bunch of different ways, but their conclusion was that “Balsam Fir needles kill overwintering ticks under both field and lab conditions”.

This is just another reason to love Balsam Fir trees. The picture above was taken at altitude above the field school, and just look at all those beautiful Balsam Fir trees! But don’t take my word for it, go read the article (see link below). And for more information on Balsam Fir, the state of Maine has a great book called Forest Trees Of Maine that is free online. Here’s a link to the section on Balsam Fir (pdf).

https://www.nature.com/articles/s41598-022-15164-z – “Balsam fir (Abies balsamea) needles and their essential oil kill overwintering ticks (Ixodes scapularis) at cold temperatures”