Tree News

Easy Tree ID

You are driving along Pennsylvania highways and notice a scattering of small to medium size trees with the leaves turning brown in July or early August. What's going on here?

There is a very good chance that you are seeing the black locust (Robinia pseudoacacia). Our common locust is frequently spotted in abandoned farm areas and in scattered strips bordering highways. The dark leaves are caused by the locust leafminer (Ondotota dorsalis). The damage is generally uglier than it is desctructive.

I will soon have a complete profile on Robinia pseudoacacia in the Tree Profiles feature.

When you head into the woods across most of Pennsylvania and find a tree with opposite leaves, it is most likely a maple or an ash. If the leaves are simple, it would be a maple and, if compound, an ash. There are exceptions to this rule, and in future posts I will cover those exceptions (buckeyes and catalpas).

I offer the comparison of ash and maple tree leaves as a demonstration of how easy it can be to start mastering tree identification. It is only a first step, but I think you will be pleasantly surprised with your increased level of awareness with respect to trees if you start with that tidbit.

I think the most effective and fun way to identify trees is to begin by learning some general distinguishing features of groups and families of trees.  You can, of course, identify a tree with a good taxonomic key, but then you will have only learned a single tree (I will, of course, discuss using keys later and recommend quality field guides that include comprehensive taxonomic keys).

While running a series of posts on tree identification, I will also be gradually implementing several of our key features on Trees of Pennsylvania. These features include:

Tree Business/Organization Directory - I would like to develop a comprehensive directory of all services related to trees or forests. This will include consulting foresters, woodland associations, conservation organizations, outdoor equipment, and much more.

Tree Identification Guide - This will start with an overview of the tree species you are most likely to encounter in Pennsylvania's forest. Then I will add information on non-natives, including landscape trees and invasives. While compiling the tree profiles, I will be working on our own Trees of Pennsylvania Tree Key.

Campus Tree Gallery - I am working with Mt. Aloysius College in Cresson to put together our first Campus Trees page. We believe that these campus trees pages can be both beautiful and educational.

Please let me know if you have any suggestions for other information or features related to trees and forests.

I would like to recommend webinars from the Penn State Department of Agriculture Cooperative Extension. Webinars are scheduled for the second Tuesday of each month, and planned topics include: bats, management plans, small-scale farming, turkey, emerald ash borer, regenerating a high-grade stand, early successional wildlife habitat, oak managment and regeneration, and hemlock wooly adelgid.

Visit the Webinars main page for more information and to register.

A surprising number of deciduous trees maintain some of last year's dead leaves well into late winter and even early spring. I took this picture of a young sugar maple on Feburary 18th of this year. However, it seems that lingering leaves on sugar maples are more the exception rather than the rule. It is very common, on the other hand, to find last year's leaves on young beeches and the lower limbs of white oaks of any age.

A brief period of sunshine with a little rain in the area, and we were rewarded with a rainbow in the backyard October 13. I actually had my camera ready to check out out the foilage. The larger image below includes the sugar maples, butternut, and ash that I was investigating:

The evergreen tree in your yard has lots of brown needles and it's shedding them. Is this cause for concern? Generally speaking, no.

Evergreen trees, including pines, hemlocks, spruces, and firs loose their needles periodically. The white pine (Pinus strobus) pictured here has a typical appearance for a tree shedding its needles.

If you have been seeing a small tree with red fruit that doesn't seem familiar, it may be that you are noticing the hawthorn for the first time. Although I don't know if it's true over a larger area, it seems that the hawthorn is having an exceptional year for producing fruit over parts of central Pennsylvania.