I like trees

Today I wandered into another part of campus I've been meaning to go to since I got here but never found the time to. I went to the F.R. Newman Arboretum. An arboretum is a collection of trees only, although generally the have woody shrubs and underplantings of herbaceous plants. Many arboretums were created as a way to display trees and shrubs that grow in the climate and region the arboretum is located. I have liked trees for as long as I can remember. The first picture I drew was a tree and even though I like plants in general, I love trees above all. The arboretum is where I am at home.

Seems like a lot of grass. Room for expansion.

I wandered through the grove of nut trees by Fall Creek (Another place I want to go through). The road followed a ridge  where on the left was the wooded valley leading into Fall Creek and on the right were the managed plantings of the arboretum. The woods are probably second growth forest from when the area was logged, based on the fact that the slope is probably too steep for farming. The area has an canopy of Sugar Maple, Oak, and American Beech, with an understory of young hemlocks, which will one day make up the climax forest given enough time.

Woodland vs managed plantings

But these forests will never be the same as before we logged them. The entire ecological system is different and is still changing. Generally, we tend to focus on the negatives with the assumption that the past what is desired. With environmental restoration, we strive for the pure and untouched ecosystem that predates human settlement. We call unlogged forests "virgin" growth. Hoewever even these tracts have been changed, probably irreversibly. Introduced species and diseases are changing the forests. Not that they haven't been for hundreds of years.

On the left of the previous photo, one can see a tree with bright gray bark. This is the venerable American Beech, one of the dominant trees of NE forests. It probably won't remain so for very long. Around 1890, the insect, beech scale was introduced to Nova Scotia. The beech scale sucks the sap of beech trees and the wounds are a open path for a fungi Nectria coccinea var. faginata to enter and infect the tree. In an effort to stop the infection, the tree kills off tissue surrounding the infection site, causing sunken cankers in the bark. Since there are many infection sites, the cankers cut off nutrient and energy flow between the leaves and the roots and the top of the tree dies. By 1932, the disease had spread into Maine and since then it has continued its slow march south,. The infection front is currently in Pennsylvania. Many of the beeches in the Ithaca area show signs of of infection, and this one is no exception. The normally smooth bark is pockmarked by cankers. Tree mortality stands at 30-50%, with many of the survivors being damaged and susceptible to other stressors. Unfortunately, there is no treatment for either the fungus or scale. Trees that are infected can also regenerate from root sprouts although these are quickly infected too and do not gain much size.

To add insult to injury, someone has carved things into this specific tree. Beeches are favored for "X was here" carvings due to their smooth bark. In the past, this may have had been simply a cosmetic injury to the tree, but since the beech scale finds shelter in these rough cuts, this makes the trees more susceptible to the disease. Sadly, either way, this tree was probably going to go out someday. The bright side is that there are resistant trees that seem to be able to prevent scale infestation and therefore the fungus invasion. Although it may seem counterproductive, it is recommended to kill any infected trees that resprout. This would allow the resistant trees to proliferate and decrease reservoirs for disease. It is my hope that we will be able to develop resistant varieties of not just beeches, but also other trees that once populated our forests that have been killed off by disease. I would also love to be able to contribute to the effort as a plant scientist.