kreischer hill rare plant community

Protectors of Pine Oak Woods · Current Issues · Kreischer Hill Rare Plant Community

Forest Restoration
By Don Recklies, Naturalist

High Rock, May 2010

Protectors of Pine Oak Woods Restoration Workshop for May had a slim turnout, the majority of our regulars having gone to Cloves Lakes Park for the second of a series of three Natural Resource Group classes in removing invasive species from New York City Parks. The remainder (all two of us) met at High Rock Park to assist in planting and invasive removal for It’s My Park Day. There we joined the High Rock staff and about a dozen other volunteers to plant 150 trees at three different locations in the park. Saturday was sunny with temperatures rising to about 70 by noon, just a superb day to do some outdoor planting.

The planting at High Rock was done as part of the “Million Tree Initiative”, a 10 year New York City partnership project to plant a million trees throughout the five boroughs by 2017 in attempt to increase the city’s tree canopy by 20%. The benefits foreseen from this endeavor (apart from getting more people out and active in our parks) include cleaner air, lower city temperatures - or a least a slowing of rising temperatures - and an improvement of the environment’s ability to hold water and slow run-off, thus making better quality natural habitats. The project is well underway with over 200,000 trees having been planted in the project’s first two years. The project primarily aims at providing more street trees, although, as at High Rock, some trees are being added to our natural areas. For Staten Island, the High Rock tree planting was to be the last for this spring season, hot summer weather being more difficult for transplants than any other season, and will resume in the fall.

I have had mixed feelings about the Million Tree Project being applied to Staten Island natural areas; I wondered if the project might result in numerous trees being shoe-horned into already forested locations merely to meet the goal of a certain number of trees set into the ground. Saturday’s planting at High Rock, however, seemed to be well planned with the majority of trees being allocated to two areas in particular need of help: one was on a “desire line” running uphill from the High Rock entrance that the staff was trying to close off, and the other was at the northern??? end of Loosestrife Swamp where the recent heavy storms had felled several trees, damaging the plank walk there and opening that formerly shady corner of the swamp to the sun. (Loosestrife Swamp gets its name from the Swamp Loosestrife (Decodon verticillatus), a native wetland shrub sometimes called Water Willow, and not from the invasive European Purple Loosestrife (Lythrum salicaria) that thankfully has not gotten a foothold there.)

I had never heard the term “desire line” or “desire path” path before, but I find that it is a legitimate term, and refers to unofficial woodland shortcuts created by people or animals where existing trails don’t go directly enough to a desired location. Crossing trails in the woods often acquire such shortcuts at each side of their intersection wherever hikers see an easier way to cross over to the other trail. Generally we are encouraged to use official trails in order to discourage creating paths in inappropriate places, either to prevent these unofficial paths from becoming sites of erosion on the hillsides, or to preserve areas where sensitive plants and animals might live, or even just to discourage wandering feet from further compacting soil in the forest. Closing these pathways by planting trees in them is often effective, especially if the trees are densely planted where the trails start and are large enough to attract notice. Most people won’t disturb obviously new plantings. The trees, however, have a tough time of it; the soil on the trail has been pounded by the passage of many feet making it hard for both roots and water to penetrate, and the path itself is denuded of the leaf litter that nourishes the soil as the organic matter decays and prevents the soil from drying out. Because of this some trails can exist for decades after they have fallen out of use; the ground has been pounded into a cement-like consistency in which few plants can get a foothold. Moreover, sometimes people accustomed to using the path are difficult to discourage. Participants in Protectors restoration sessions several years ago attempted to close off such an unwanted pathway off the High Rock Green Trail because the steep hill there was becoming severely eroded. We planted trees on and alongside the unwanted trail (many fewer than were planted last weekend... if I recall we had only about eighteen for the first planting session there), and dragged as many fallen trees and branches as we could to block the pathway at top and bottom of the hill. In those days we rotated sessions between four sites, so we would return to the same place about every fifth month. Invariably we had to drag our makeshift barricades back in place. Today that pathway is mostly unused, but the soil had been so damaged that the path’s course to the bottom of the hill is still visible - but there are a few trees growing in the middle of it to mark it off-limits!

The second planting site at High Rock involved a different situation entirely. Wherever there are blow-downs in the woods there is an influx of light to the forest floor giving opportunity, for a short time at least, for shrubs and forbes that need sunlight to flourish. As seasons pass the glens created by fallen trees see a succession of plants beginning with grasses and such plants as Goldenrods and Asters and other sun-loving types, and later shrubs and vines such as Poison Ivy, Virginia Creeper and Cat Briar. These vines are natives, and although they can form an impenetrable thicket that is good cover for small mammals, they are not likely to harm the trees because they do not climb by twining. Gradually saplings will force their way through these shrubs and vines to the light, eventually growing up to fill the hole in the canopy and re-creating the shady forest floor that was there before. In the meantime these glens and forest gaps provide a welcome change of pace for those of us who walk what are mostly shady trails. There we can pause and see things that are different; these glens form an “edge community” - what ecologists call an “ecotone”, although that term is usually applied to larger areas with longer borders. These area are species rich, inhabited by both sun and shade dwellers. Many birds inhabit these edges, feeding on insects in the sun and fleeing back to the forest edge for cover. There we might see Brown Thrashers (if we’re lucky) and various Fly-catchers. However, it is not always good when more light gets to the forest floor. The light not only enables native plants to flourish, it also stimulates the growth of alien invasive species, many of which are quicker to seize the opportunity than the plants we desire, and all too often a newly opened glen becomes covered with Japanese Honeysuckle and Oriental Bittersweet climbing over and strangling understory shrubs, often using them as a scaffold to get high into the surrounding trees. Planting new trees in the open area at the end of Loosestrife Swamp and shrubs, as we were told was planned for next year, jump-starts the natural succession and hopefully discourages alien invasive species from moving in.

The trees planted there included Black Birch (Betula lenta), Sweetgum (Liquidamber styracifula), Red Maple (Acer rubrum), and Scarlet Oak (Quercus coccinea), all good choices except, perhaps, Scarlet Oak which I believe prefers drier, more well lighted areas. These are all trees native to Staten Island, and were most probably raised at the Native Plant Center nursery close to the William T. Davis Wildlife Refuge. Planting locally grown trees is important for a successful outcome. Why should we prefer locally grown you might wonder, why not just take the lowest bid from any nursery in the nation and get the most bang for the bucks spent? Red Maple, for instance, grows almost all over the east coast from Florida up into Canada and west to the Mississippi and beyond. Maybe Red Maples from Pennsylvania or Ohio might be cheaper. Ignoring issues such as transportation costs and burning more fossil fuel - important as these issues might be - we find that locally grown trees have a better survival rate than imported trees. For one thing, they have been stressed less by the rigors of traveling long distances, and for another, they are already somewhat adapted to the environment in which they will be planted. If you were to go to the internet and search out descriptions of the environments in which Red Maple grows, you would no doubt find that it does well in wetlands such as riverbanks and swamps as long as its roots are not flooded for long periods; but if you looked at some other sites, you might find that it does well in well drained soils or on south facing slopes or on dry ridges. You might also find sites that say it prefers sun, and others that say it tolerates partial shade. Can so much information out there be wrong (actually yes, but not in this case)? The fact is that Red maple is a highly adaptable tree that grows well in widely different environments; the trick is that while these trees can be found in all these different places, once they have adapted to a particular environment they or their seedlings will not do well if they are transferred to someplace different. Staying local is better. Well, getting back to High Rock, all the trees were planted randomly some 5 to 6 feet apart in holes prepared by the High Rock staff using a power auger, a device that removed a large part of the drudgery of the work. Apart from a disagreement between the narrow footbridge at the south end of the swamp and the park’s small utility vehicle, the work went very smoothly, all 150 trees being set in place by 1:00 (and the small truck and the footbridge patched up their disagreement). Once the planting was finished and we were returning to the administration building for pizza provided by Parks I took the opportunity to uproot whatever Japanese Barberry and other invasive aliens I encountered on the way. (The pizza may have been subsidized - and no, we didn’t go to plant just for the pizza - if so I regret I didn’t catch who the provider was.)

After out last restoration session at Great Kills I commented about the vanishing serpentine barrens on Staten Island, and a long time member of Protectors wrote to comment that the Greenbelt Master Plan expressed a determination to preserve them, but nothing has been done. That aim is indeed in the Master Plan, but as we all know expressing such a goal doesn’t necessarily guarantee funding and action. At It’s My Park Day I inquired if it would be a good idea for Protectors to schedule some sessions this winter to cut back what we could of the shrubs and saplings that have sprung up on the barrens east of Seaview Hospital. In that place what was formerly an extensive open hillside is now largely covered by Sweetgum and Quaking Aspen, some of them quite large. I was encouraged to hear that the Department of Parks was trying to contrive a plan to restore the barrens. Aware that fire, the natural and probably best method of restoring the barrens, is no longer feasible, Parks plans to reach out to those responsible for maintaining similar barrens in other areas for advice, and then hopes to set up test plots on the barrens to work out a method of maintenance appropriate to Staten Island. The impression I got was that it would be preferred that we didn’t disturb these barrens until an official plan was worked out. Given the current state of the budget for parks in New York City, I am dubious that this will be accomplished in the near future - or perhaps even the distant future - but one always hopes.

The financial situation for the Department of Parks and Recreation can only be described as dire. Parks has successfully - for the most part - weathered a budget that year after year falls short of covering the multitude of tasks it must accomplish by enlisting volunteers to take over some of these chores, but the current cuts makes it almost certain that there will not be enough supervisors for this volunteer force. In the last few months the city announced that the budget necessitated cuts representing the loss of almost 500 full time positions, with reduced operating hours and even the closure of some facilities this summer. We know these cuts are short sighted, and it is to be feared that unless the situation reverses itself our park system will degenerate to the bleak days of the 70's. I don’t know how this will ultimately affect the Greenbelt, but given the state of the current budget, I see little hope that anything can be accomplished on the barrens for several years.

Another local habitat that I believe is in some danger are the kettle ponds that stud the Greenbelt, Loosestrife Swamp being a case in point. Loosestrife Swamp used to be a kettle pond, a depression in the earth formed by large chunks of ice left behind as the glaciers that once covered Staten Island 20,000 years ago retreated. Because of the way they are formed, kettle ponds sometimes exist without streams running into them, and instead are often filled by rainwater. Such ponds may go through a succession of development just as fields reverting to forests do (only wetter). Generation after generation of pond weeds and other floating aquatic plants die, decay and sink to the bottom while the remains of emergent water plants such as Arrow Arum (Peltandra virginica ) and Duck Potato (Sagittaria latifolia) and various sedges build up soil around the edges. The ponds get smaller and shallower until finally they become first swamps and then wet forests. Loosestrife swamp seems to be well into the swamp stage, and here and there is studded with tussocks of sedge and other plants that have grown large enough to support small saplings. Dick Buegler recalls that as a child Loosestrife swamp was open enough that he and other would skate there in winter. You certainly couldn’t do that today.

I wondered if perhaps plans could be made to preserve the kettle pond environments, especially since Staten Island now has only a small fraction of the wetlands it used to have and far, far fewer amphibians and invertebrates that depended upon those wetlands. Perhaps such ponds could be sequentially dredged every 15 or 25 years, a small section at a time, to preserve the depth of the water. Maintenance of these ponds, however, might be more difficult and expensive to accomplish than maintaining the barrens. It would certainly require careful study and planning lest more creatures and plants be lost by dredging than saved by an attempt to maintain their environment. There would be the problem of getting large equipment in and out to do the work, and then the problem of what to do with the dredged spoil. It’s simple to ruminate about remedies like this, but as they say, “the devil is in the details”, but maybe we should consider confronting these devils before Loosestrife Swamp disappears.