August 2013, Red Trail
Red Trail Forest Restoration
By Don Recklies, Naturalist
Forest Restoration Workshop #205, August 2013
August’s Restoration Workshop found five of us choosing to combat twining vines along the Red Trail close to Forest Hill Road. There we found numerous lianas of European Bittersweet and tangles of Porcelainberry that we attempted to remove from trees and saplings. The larger vines were for the most part too large and entangled for us to uproot, and these we cut as close to the ground as we could and then, if possible, pulled the already cut vines from the trees or cut them again higher to prevent them from easily growing back into the trees by means of the dangling vines. Some of the thick bittersweet vines trailed for yards through impenetrable thickets of cat-briar which we could occasionally circle around to find where the vines rooted and cut them there, but often we could only reach into the briar as far as possible and lop the vines in hope that the shade would discourage their regrowth.
Elaine has always been especially determined to pull the vines down from the trees, whereas I’m mostly content to cut them low and high figuring that they will wither away without further damage to the trees. Her trees always look better than mine (she says she can imagine hearing sighs of relief whenever she gets a tree clear), but on the other hand I can get to more vines during a session. I imagine that she probably breaks more twigs pulling the vines down, but the trail does look much nicer without cut vines hanging about at head level. I guess it all balances out.
This was our 1st workshop in this spot, but thick hanging vines previously cut revealed that others had been at work here before. Unfortunately the cut vines included several wrist-thick grapes that should have been untouched, although it is possible that these had not been cut in error, but instead to clear the trail. Because of the occasional similarity of leaves, Porcelainberry may be confused with grape – especially before it bears fruit – but should be recognizable since the bark of the Porcelainberry vine can be shreddy and tan in color, whereas a grape vine is considerably more shaggy and dark brown. If the trail was being cleared, my inclination would have been to leave the grape intact and let trail walkers dodge those vines…
Dom, who was leaving for the afternoon, volunteered to take our tools with him after the workshop so that we didn’t have to return to our cars, and the rest of us were free to enjoy the Red Trail loop on what turned out to be a very pleasant afternoon. Numerous Tiger swallowtails, both yellow and black, assiduously nectared from Joe Pye Weed in the trail clearings, and in one of those spots on the way up Hyerdahl Hill we paused to examine one of the spider webs in the catbriar beside the trail.
Spider webs seem to be much more numerous this past month in the Greenbelt, although that observation shouldn’t be surprising. This is the time of year when spiders and the insects they feed upon become most apparent. Both have been growing unobtrusively throughout the summer, periodically shedding their exoskeletons as they become larger and larger, and now they have grown enough to attract notice, even though they’ve been among us all summer long.
Not all spiders make webs, but of the web makers, we most often notice the orb weavers, because their flat webs of radiating strands supporting elegant spirals of sticky silk are most conspicuous, especially on early mornings in the woods where their habit of constructing the webs across trails can be frustrating and annoying to unwary trail walkers. Our spider was not an orb-weaver, but a relative that builds cobwebby nets among the leaves, and in his net hung a string of tiny balls appearing much like a miniature tube of garlic bulbs that we see hanging in markets. Sometimes silk wrapped packages in the webs are insects that a satiated spider has stowed away for later consumption, but these were a series of tough silk spheres of spider eggs, the sphere at one end probably full of minute spiderlings waiting to emerge, and those on the other end containing less well developed eggs. I once opened a string of these spheres, but can’t recall whether the top or the bottom contained the most mature spiderlings. Logic doesn’t help here since spiders can easily dis-assemble and reassemble their webbing; in fact the orb-weavers periodically rebuild their complex webs, eating the old silk so as not to waste the protein.
All spiders are capable of making silk, but not all spiders make silken webs to capture prey. Some spiders use their silk only to line holes where they can lie camouflaged in wait for passing prey and some spiders use their silk as wrappers to protect their eggs, or, as with our spider, to do both. Some use the silk as life lines to ascend or descend or, when they are small, as parachutes to waft their bodies to new places. The possession of abdominal spinnerettes for producing silk are one of a spider’s defining characteristics – as well as fangs, poison glands and – unlike the insects they feed upon – four pairs of legs.
In the spider clan, the orb-weavers and cobweb makers have the most highly developed spinnerettes and build the most complex webs. Arachnologists tell us that up to six distinct types of silk may be required to build an orb web; some strands are sticky and some dry, some are elastic and some don’t stretch much at all and are meant for climbing or anchoring other parts of the web. The spiders that produce these complex webs with multiple kinds of silk are evolutionary latecomers, and many references refer to them as “advanced” and the other spiders as more “primitive.” These terms, however, don’t imply that the orb-weavers are necessarily better than the others; they are only terms that indicate their position on an evolutionary timeline.
There’s a bit of a parallel in botany where we consider seed bearing plants, the angiosperms which in the history of the world have evolved latest, to be more advanced, and the families that developed millions of years before the seed plants to be more primitive. We subconsciously apply a kind of value system to these descriptions, that the more “advanced” plants (and spiders) are somehow better than the “primitive” ones. The truth is that the development of seeds allowed angiosperms to occupy drier environmental niches that were at the time vacant so that they did not have to compete with the other long established families of plants that required wet places for reproduction. Without seeds to allow those plants to colonize drier lands the newcomer angiosperms would have had to compete with the already well established mosses, liverworts and ferns, etc. Likewise with the spiders, development of newer, different types of silk permitted some to produce elastic, aerial webs that could be used to capture high flying insects that were out of reach of the others; the “advanced” spiders were able to occupy newer niches, while the more “primitive” spiders successfully continued to pursue their prey on the ground and low vegetation. Both the “advanced” and “primitive” spiders are doing well today.
My attention was so focused on the web and spider that I was startled when Armand pointed out that I had not seen a frog immediately to the left in the Catbriar beside the web. The frog, which clung motionless to the leaf with little suction cup toes, was a Grey Tree Frog, the only tree frog that we are likely to find on Staten Island. Our frog was more a pebbled lime green than grey, but the very similar Green Tree Frog isn’t supposed to occur as far north as Staten Island. Reading up on the Grey Tree Frog elicited the information that this frog can, like chameleons, vary its coloration to suit its surroundings, although more slowly and to a lesser degree. I had long thought that Spring Peepers, those tiny frogs bearing a more-or-less distinct crossmark on their backs and which also use little “suction cup” toes to climb low hanging marsh plants in Spring to find a site to sing, were also tree frogs, but a reptile and amphibian expert from the Hudson River Museum informed me that they are not considered to be “true” tree frogs. The reason seems to be that Spring Peepers, unlike true tree frogs, do not spend a considerable part of their life high in vegetation. I suppose just like that word “primitive,” we have to know the particular implications of “true.”
At the east end of the Red Trail Loop close to Rockland Avenue we passed an area where the Department of Parks Natural Resources Group has begun a major restoration in the Greenbelt. What had been a mound of Oriental Wisteria is now a barren field, the wisteria grubbed out of the ground and the remainder treated with herbicide. Along the edges of the wetlands are silt fences of hey bales, rolls of coir and bands of geotextile fabric stretched between poles whose purpose is to prevent silt from the denuded areas from filtering into and clogging this branch of Richmond Creek. This project, scheduled to take place over several years, is planed to aggressively continue to remove invasive species from the area around the creek and to replant the unvegetated area with native plants. The technique is similar to that the Department of Parks is employing at Crooke’s Point and has employed at Clove lakes Park. Many are not convinced that this is the best method of managing aggressive, alien invasive plants, but I believe that in this highly degraded area Parks did not have much choice other than letting Nature and the alien plants take their course. Time will tell if their Draconian method will be successful, but for now the trail crossing close to Rockland looks devastated indeed. Two walkers asked us what was going on there, and when we replied that it was a forest restoration project, they replied that it looked more like a forest destruction project. The site really needs an explanatory billboard! I had planned to include a link to the PlaNYC plan for this project should anyone want to look at the details, but haven’t been able to locate it on the web. If I find it, I will note the link in the next restoration report.