Reading the Forest: Lessons from Our Local Woodlands

In our area we are fortunate to be able to see all types of forests in various life stages. You may not even consider what you’re looking at as a forest stand that’s going through a certain phase in its life, but from suburban neighborhood to single trees in the city, they’re all   affected by certain phases and responses to their surroundings.

I grew up in Bon Air just on the south side of the James and went on to study forestry in Tennessee. While I have been back home now for a number of years, one of the greatest lessons I had while in school was walking through an agricultural experiment station in west Tennessee. Dr. Allan Houston was leading our class in the field while talking about stand dynamics and other random stories as we went. Very purposefully, he stops in what you would call the middle of nowhere and suddenly asks the group what would turn out to be the lesson for the day.

“Take a look around. What do you see? How did this happen and what do you think this was?” He’s silent and walks away for us to figure this out. As it turns out, we were standing in the middle of flat ground, typical of west Tennessee and surrounded by what looked like thousands of thin Yellow Poplar trees, every one of them probably thirty feet tall. The only other major observation were a few much larger trees, all in straight line, thick trunks and large limbs all reaching in one direction and low to the ground. Behind them was what seemed to be hardwood woodland. One of the large trees was dead I recall and only the main structure of the tree was left. The group of us looked around to see if anyone had a clue to the trick question. There were attempts at answers, all were incorrect. I’d say at that point none of us had ever considered what the trees and the landscape were telling us.

We were standing on an abandoned crop field that the University was now using for research. The field was unused and left to revert to native vegetation. What had grown up in its place were the thousands of Poplars from the adjacent woods that had lay dormant in the soil and spouted from lack of activity in the field. The big old trees were the old field line where they had been reaching for sun into the open field for decades while the land was farmed for crops and pushed by the neighboring woods. That simple observation tied land use, forest stand initiation, tree growth and maturity all into one visible and valuable lesson.

Trees will inhabit an area whether you want them to or not. That’s their strategy, and they’re pretty good at it. Seeds lay dormant in the soil for years just waiting for the right circumstance to prompt germination. Something as simple as one more hour of sunlight from a fallen tree or a house being built and you’ll see a flush of new growth within weeks. That’s exactly what happened on our old farm field when it went from row crops to bare soil.

There are four phases when it comes to stand initiation: Initiation, Stem exclusion, understory re-initiation and eventually old growth. Primary succession species, or Pioneers will initiate a piece of ground that has just been disturbed and is now close to bare soil with plenty of sunlight. These Pioneer species like Poplar, Sweetgum, and Pine will be the first species to grow and take over these areas since their seeds are carried by wind and can lay dormant easily for years. They are sun loving and will rapidly grow vertically until all resources like sun, water, nutrients and space are completely taken. At that point, every single individual will stagnate and hardly grow under heavy competition from their own neighbors. This lack of vigor and fight for resources begins the next phase of our new forest stand, stem exclusion.

At this point, individuals or groups of pioneers dieback and are excluded from the stand. The fallen foliage from the pioneer trees that has built up over the years helps create a rich seed bed for the Oaks, Hickories and Beech that small mammals and birds carry in and roll in from neighboring trees. These secondary succession species will have begun to germinate from the shade that’s cast on the ground. These species can germinate under heavier shade and will wait in the understory until the pioneers give them the opportunity to grow into the upper canopy through stem exclusion.

This process creates the understory re-initiation. A second wave of seedlings and saplings will have germinated since their specific conditions will have been met underneath the canopy, and as more light is able to reach the floor the shade-loving species can then grow up through the Poplars and Pines. This takes a very long time, but eventually Oaks, Hickories and Maples will become a larger component to our stand. There will be plenty of pioneer trees left, but only the ones that made it to the top of the canopy and were able to outcompete their neighbors.

I shouldn’t say finally, because forests have many phases, but a Mature stand, or “Old-growth” you’ll normally hear is a forested area that has been allowed to follow natural forest succession on its own for decades or even centuries. These actually are the most diverse forests since they are always experiencing each forest phase as a single tree dies, or weather blows a group over. The main distinguishing characteristics to them is that the primary overstory trees are the climax species that take the longest to develop and tolerate the most shade. In our area you’ll see primarily Beech, Oak, Sourwood and Hornbeam. From there, any time a large overstory tree goes into decline, the process starts all over again in the newly disturbed area the old tree once stood.

Our area is made up of a patchwork of land use history from untouched woodlands, farmland, mining, timberland to urban and rural development. I tend to think back to Dr. Houston’s lesson more so than the average guy, but I also look at trees and woodlands every day. So, while we have been building and expanding our city, the woods and land surrounding it have responded, grown or have even been removed. It continues to grow with us though. We can see those phases of forest stand development if you stand back and take a closer look at the structure and individual canopies. We can certainly appreciate those big open grown specimen trees at Maymont, along Buford Road, Hollywood Cemetery, Church Hill and Lewis Ginter. Let’s not forget though the ones that make up the structure of our neighborhoods and communities that have been growing with us for years. Take a look around next time you’re out and see if you can tell what phase your forest is in.

-Mike Carr, 2/27/26