As the Zoom presentation by Jennifer Allcock on November 17 made clear, the Big Woods (85 acres of forest between Kendal and Crosslands) needs help, and many residents are eager to help out. (If you weren’t among the 80+ residents who watched the presentation “live”, you can watch it on YouTube here.) But as the Q&A following the presentation also made clear, there are many opinions about what to do next.

I want to make sure readers know that, up until this fall, I had very little real understanding of the state of the Big Woods (although I often walked there). Thanks to conversations with experts on our two campuses, I am much better able to discuss the issues. In particular, I have been greatly helped by (in alphabetical order) Jennifer Allcock, John Barbis, Kathleen Gordon, and Tat Smith. (However, they are not responsible for any errors or misunderstandings in this blog post!)

In the first part of this post, I will present some background information on the state of the Big Woods. Then, I will present some ideas for fixing the problems, and some of the questions surrounding the various options.

The state of the woods. For me, a key takeaway from the November 17 presentation was that the Big Woods faces a triple threat. The three big threats (in no particular order) are:

  1. Erosion from stormwater, and soil loss from suboptimal operation of the spray fields
  2. Invasives (including plants, diseases, and insects)
  3. Loss of young trees and understory plants to overgrazing by deer

Tat Smith, who is a retired professor of Forestry, notes one additional threat: climate change. In particular, the Big Woods may experience more frequent and fiercer wind storms, and may lose additional trees as a result.

Those issues must all be taken into account, and some remedial efforts are already underway. In this initial post, I will focus on the deer, and the pros and cons of a deer fence. In future blog posts, I hope to touch on the issues of erosion/runoff and invasives.

Approximate area of the Big Woods. It is bounded on the west by the Longwood Gardens property line, on the east by the maintenance road, and on the north and south by the Crosslands and Kendal landscaped areas.

Why the status quo can’t continue. I believe there is general agreement that our woods is headed for trouble and intervention is necessary. The most obvious signs are growing gaps in the canopy (the uppermost layer of leaves) and an unsatisfactory understory (the plants that grow underneath the trees of the canopy)—these plants are increasingly invasives.

The canopy gaps occur where mature trees have died naturally or have succumbed to root rot, leaving an area of the canopy without leaves. If you stand in one of these gaps, you can look up and see an open area of sky. One would hope that new young trees would spring up to replace the ones that died, but that is not happening. Instead, the gaps persist and are becoming more numerous and larger. The character of the woods is gradually changing. I think there is general agreement that somehow we need to ensure that new trees will populate these gaps. If we don’t, the Big Woods will evolve into something unrecognizable as a forest.

 At the same time, the nature of the understory has changed. In parts of the Big Woods, the diversity of plants that once occurred has been replaced by sparser and far more limited species. In some areas, virtually the only plant remaining in the understory is spicebush. Spicebush (which is native to this area) is not the problem: the problem is that most of the other plants have disappeared, probably due to grazing by deer (which will eat most plants, but don’t like to eat spicebush).

This degraded understory is an example of lost biodiversity. Without a wide array of plants, it fails to support the varieties of insects, small mammals, birds, lizards, soil micro-organisms, and so on, that normally populate a forest and keep it resilient. A forest that is not diverse is an unstable forest. As with the canopy gaps, it seems to me that there is a consensus that something needs to be done to help the understory recover.

Is the local deer population changing? Is it under control? Unfortunately, it is hard to tell if there is any trend in deer numbers. Each year, before the annual deer “harvest” (the preferred term used by Casey Groff, who is in charge of this effort), a rough assessment of the local population is made. Volunteer staff members go out into the woods with a search light after sunset and see how many deer they can spot from a prescribed set of locations. I spoke with Casey about the counts, and he reports that the numbers reported now are roughly similar to what they were in the 2008-2013 period when this process began.

Similarly, the trends in the number of deer taken each year are hard to interpret, depending (as they do) on the number and activity level of the hunters as well as the deer population itself.  So we don’t really know how many deer are in our area, or how the hunt is affecting that number.

When I spoke with Tat Smith about this, he encouraged me to look at the state of the woods, not any particular level or trend in deer counts, in determining whether the deer population is a problem. And if we take the state of the woods—especially the lack of young trees—as the relevant indicator, I believe most residents would agree that the deer population is definitely too high.

Why we can’t go back. One idea for the Big Woods is that it should be restored to “the way it used to be”. On the surface, that is an attractive proposition. But it isn’t the basis for a realistic plan. Before the arrival of European settlers, the area had a population of wolves and bears as part of the ecosystem. They won’t be coming back. Later, farmers settled here and cleared the area for fields and pasture. A century or so ago, I am told, the entire area that is now the Big Woods was mostly pasture, without many trees. The Big Woods is a relatively recent phenomenon. There isn’t really an obvious state that we could decide to return to.

If we can’t go back, we must go forward. That means deciding what kind of woods we want and what steps we are willing to take to reach that state. Reaching some level of agreement on where the Big Woods should be heading would be a major step in planning.

Is Tyler Arboretum a good model for our Big Woods? Before tackling the details of a potential fence or other interventions, there is a more fundamental issue to explore, one which I have not heard directly discussed in public. That is: what do we want the Big Woods to become?

There isn’t a consensus about the answer to that question. This became clear to me during a long conversation with John Barbis. We were discussing Tyler Arboretum, a 650-acre preserve half an hour east of Kendal. For more than 20 years, Tyler Arboretum has had a deer fence around 110 acres of its property. A sizeable fraction of that is woods. (There is also another, smaller fenced area elsewhere on the property.) I told John that (based on my recollection from visits a few years ago) I liked the Tyler woods better than ours, given the current state of ours.

John is familiar with Tyler Arboretum, and he definitely does not like the Tyler woods. To him, a fenced woods is something akin to a garden—a space where humans have taken control and eliminated whatever aspects of the natural world they don’t like (mostly the deer, in Tyler’s case).

Jennifer Allcock recently visited Tyler Arboretum. To her, the woods inside the fence seemed healthy and not overly managed. That is her objective for our Big Woods. With the current excessive deer population, she believes, “there is no way natural regeneration can occur”.

Kathleen Gordon, who has volunteered at Tyler, tells me that a major motivation for their fence was to protect the famous collection of azaleas and rhododendrons growing there.

The fence does accomplish that goal, but we are fortunate that Tyler ended up fencing in far more than just their azalea and rhododendron garden. Also inside the fence are numerous other features for visitors, including a significant woodland area (which Tyler calls “the North Woods”). That means visitors can compare wooded areas inside and outside the fence, and a number of gates that lead to hiking trails make it easy to experience the woods on both sides of the fence.

Given the divergent opinions about Tyler Arboretum’s fence, I decided to revisit Tyler myself. Together with my wife and visiting daughter, we spent a few hours there on December 30. We looked at the woods both inside and outside the fence. Outside the fence, the impression is similar to our Big Woods. Most of the understory is beech saplings and spicebush, with very little diversity. Inside the fence, there is a dense and diverse understory. (I’m not a plant person, so I can’t tell you exactly what was growing there.)

I encourage readers to visit Tyler Arboretum. Check out their “North Woods” (inside the fence), then leave the fenced area and check out the adjacent woods there. Perhaps that will help you decide which you would prefer. Also worth noting while you are there: the deer-proof gates where hiking trails leave the fenced area are self-closing and easy to operate.

John’s opposition to a fence like Tyler’s is what I would term “philosophical”. He would like to see us work with nature to the extent possible to restore the woods to a healthier state, without a fence. A fence, he feels, would prevent the gradual working of natural forces and require an unnatural level of human management.

Kathleen agrees with many of John’s ideas in principle, but feels that the Big Woods has deteriorated to the point that it is too late to implement them. She feels a fence is necessary to “stop the hemorrhaging”.

Tat Smith emphasized the need for biodiversity in the Big Woods, ranging from the organisms of the soil, to the understory plants, to the mature trees. Only with diversity could our forest thrive, while also retaining the flexibility to deal with future climate change. And, he noted, “you will not get full ecosystem diversity with current levels of deer browse.”

John, Kathleen, Jennifer, and Tat all had considerable overlap in their opinions about the need for a healthier forest, and what that forest should be like. The main disagreement seems to be the degree of human intervention that is desirable (or required) to achieve that result.

What actions should we take?

The Big Woods Strategic Plan Team, consisting of residents and staff, spent long hours putting together their ideas for what needs to happen with the woods. The plan has just been published in the January issue of the Crosslands Chronicle.

Neither the Strategic Plan Team nor the four residents I have quoted here can represent the views of every resident, of course, and even if we got agreement on the right outcome for the Big Woods, there could still be disagreement on what action should be taken to get us there. Here are some ideas that are under consideration.

A deer fence. The most-discussed option is a fence. One focus of the November 17 presentation was the damage from deer browse and the potential for a fence around the Big Woods to keep deer out. In the subsequent Q&A, there was general acknowledgement that the deer are damaging the woods, and a fence seemed to be the leading option for fixing that problem.

But at the same time, there was significant opposition to a fence. There seemed to be two main arguments against the fence. One was described above: a fenced forest is less “natural” than an unfenced one. The other had to do with the damage that deer might do elsewhere if they couldn’t browse in the Big Woods. (Some argued that the deer would browse residents’ flower gardens instead. See below.)

Any plan for a fence would need to incorporate gates at all points where the fence intersects one of the trails.

Seedlings in tubes. Young trees in the canopy gaps often get eaten before they get a chance to grow out of the reach of deer. That has led to the planting of many seedlings in plastic tubes. That can help, but only in canopy gaps and only for trees. It is no help for the other native plants that are being wiped out by the deer, including most of the native understory plants.

Plastic tree tubes are used to protect young seedlings in the Big Woods.

More aggressive culling. Culling (controlled deer hunting) on Kendal-Crosslands property is done by bow hunters, and on Longwood Garden property by sharpshooters. Culling has proven insufficient to adequately control the deer problem, but the Big Woods would surely be in even worse shape without it.

There is the potential for a “deer drive” this winter to force deer onto the Longwood Gardens property, where they can be culled by sharpshooters. If that happens, we should get some idea of the effectiveness of that approach, based on the number of deer killed as a result of the drive. The deer census in the following year or two should also show a decline. Still, deer populations recover quickly (doubling in as few as 2-3 years) so the deer drive would have to be repeated regularly.

The call for more research. One idea, put forward by John Barbis and supported by at least one other Crosslands resident, is to conduct a test planting of seedlings of desirable tree species. I can imagine, for example, a test involving an area with no fencing and an adjacent fenced area, both treated the same, to test for survival with and without fencing or any other protection from browsing. John believes a significant fraction of the unprotected seedlings would survive. John also thinks an analysis of other factors (including the quality of the soil, the prevalence of seeds, and germination rates) should be analyzed before any decisions are made.

I discussed the idea of this type of research with Tat Smith, and he thought it would be unrealistic for resident volunteers to conduct a rigorous enough test to meet the statistical requirements for a valid, reproducible experiment of this type. Tat also pointed out that testing with only tree seedlings would not be sufficient—a proper study would include understory plants too.

Jennifer Alcock notes that consultation with several experts has already occurred, and more is planned. That will address many of the questions that have been raised concerning the condition of the Big Woods.

Predators and disease. John Barbis also points out that there are Eastern Coyotes in our area, and these prey on fawns and other young deer. If the coyote population continues to grow, the deer population will come under pressure from predation. Similarly, deer in some neighboring counties are suffering from chronic wasting disease, which is always fatal. If this condition spreads sufficiently, it will reduce the deer population.

While I agree that these arguments makes logical sense, it seems to me that the big question is how fast these changes are occurring, and whether we really have time to wait to see what effect they will have. 

How can we protect people’s gardens? Several people commenting after the November 17 presentation were worried about where the deer would go if the Big Woods is fenced. Would they shift to aggressively eating the gardens of Kendal-Crosslands residents and our neighbors?  

It is not possible to know how the habits of the deer will change if the Big Woods is fenced. But Kathleen Gordon pointed out to me that fencing roughly a sixth of a square mile (our Big Woods) would leave the deer dozens of square miles of surrounding, unfenced territory, and they would probably just spread out. This suggests that a fence would not cause a significant change in the impact of the deer on our gardens or our neighbors.

As Jennifer Allcock pointed out in response to a questioner, deer are already browsing in our gardens, and she has put nearly-invisible fencing around hers. Deer repellents can also protect gardens. If deer were to remain in our area and if they chose to browse in people’s gardens in greater numbers, I imagine Kendal and Crosslands will need to help residents with garden fencing and other measures.

A “deer corridor” along Bennett’s Run? One idea that has surfaced recently is the possibility of an unfenced corridor permitting deer to pass through the Big Woods, probably along Bennett’s Run. The Big Woods would be split into two sections, one on each side of the creek, with a fence around each.

This would allow some natural deer control to take place, it would allow animal droppings to spread seeds of native plants from nearby areas, and it would allow a deer drive that would force deer over to Longwood Gardens for culling.

Next steps for KCC. After the November 17 presentation, one listener wanted to know what plans Kendal-Crosslands has for the future of the Big Woods, other than fencing, and what the cost would be. Seth Beaver responded that the plans for the woods involve more than just fencing. Runoff and the spray fields will be addressed. Ed Plasha said $10,000 is being added to the “natural area” budget line to address the woods.

Since the November presentation, a new “Woods Collaborative Committee” (one involving staff and residents from all four communities) has been established to address the Big Woods and other woodland areas. It will be headed by Seth Beaver and Jennifer Allcock. The committee met for the first time on December 17. Its members include (among others) three of the four people I depended on for the content of this blog post: Jennifer Allcock, Tat Smith, and Kathleen Gordon.

For more information:

  • The January issue of the Crosslands Chronicle contains two articles about the Big Woods. The first (starting on page 1) reflects the conclusions of the original “Big Woods Strategic Plan” team. It touches on all the issues surrounding the Big Woods and its problems. The second (on page 3) is by John Barbis. It discusses the requirements for a suitable forest-management plan. He emphasizes the need for data collection and proceeding with “all deliberate speed”.

Use the following links to watch videos of three presentations about the Big Woods

  • “Big Woods” – Jennifer Allcock – May 29, 2021 This presentation explained the rationale for a fence.  
  • Problem of Deer – NAC August 2, 2021 This presentation by Jennifer Allcock focuses on deer-related issues.  
  • Big Woods Presentation – November 17, 2021 This is a video of the presentation by Jennifer Allcock, followed by extensive Q&A, covering most of the issues surrounding the Big Woods

Adaptation Workbook—This document is a subset of the results of a program that three Crosslands residents (Jennifer Allcock, John Barbis, and Bob Shipman) participated in. It was based on a workbook from the Northern Institute of Applied Climate Science. The particular document linked here was a detailed workbook about the Big Woods and its response to future climate change. John Barbis was the primary author. (Another segment dealt with the Arboretum and landscaped areas; Jennifer Allcock and Bob Shipman worked on that part, which I have not linked here.) This 127-page report provides dozens of good ideas for improving the Big Woods (the majority of them not closely related to climate change).