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Greenbelt White and Blue Trails
By Don Recklies, Naturalist
Forest Restoration Workshop #186
December 10, 2011
A stunning day for our
186th Forest Restoration! The sky was
a crystal blue, not a trace of cloud when we started, and the temperature
rose from low to mid 40's as work progressed, just low enough to encourage
activity! However, this was an easy
morning. We had originally planned to
work along portions of the White and Blue trails south of the Nature Center,
but changed our site - for good reason we later found out - to the area where
tree planting had been done two years ago along the path to the Recreation
center on the other side of Rockland Avenue.
Japanese Honeysuckle is prevalent there in several spots - in fact a
jungle in a few places - and without intervention these young trees, nothing
more than spindly saplings, were in danger of being overwhelmed by invasive
vines. We set to work, as usual
cutting the stringy, twining vines close to the ground and then higher up,
unwrapping what we could. The vines
climbing these new planted trees were young, probably not more than two years
old, they were for the most part very thin, like spaghetti, but further from
the path in areas that had not been recently cleared or graded, there were
tough, shaggy grey vines as thick as my fingers. These thicker vines ran into the tops of
taller trees and shrubs and we cut and pulled these larger vines too. As we worked toward the Rec Center, we
found fewer and fewer vines on the saplings, evidence that others had been
doing the same favor for these young trees, but had started working from the
other end. We continued toward the Rec
Center parking lot, where we found a few large bittersweet vines that had
been overlooked. These were too heavy
for our pruners, but luckily we had brought with us a few small loppers.
We returned on the same
path looking for vines close to the trail that we had overlooked on the way
in. Some distance from the trail we
encountered the remnants of a thick, shaggy vine that had been cut from a
tree. Unfortunately this was a grape
vine, and probably a native grape.
Unlike the twining vines we set out to remove, grape climbs and clings
by means of tendrils, and usually doesn’t harm the trees. Occasionally grape may flourish and grow
out of control until it overtops and smothers the trees that support it. This rarely happens though, and since the
grape we encounter is usually a native vine, we always let it be. We hadn’t cut this particular grapevine. We try to tell volunteers to remove only
vines that they recognize, and to ask about others. For example, we point out that Multi-flora
Rose, when it is without leaves in winter can be recognized by its round red
and green stems and recurved thorns, and that
Cat-briar, a green, round-stemmed native we don’t remove, has short, straight
thorns, often tipped with black.
Grape, which we do not remove, is usually recognizable even without
leaves by its brown, very shaggy bark, and appears very different from the
grey, lightly shaggy bark of older honeysuckle vines. A non-twining vine, it climbs with tendrils
just like Porcelain-berry, another invasive we remove, but if cut, an older
grapevine will show a brown pith while Porcelain-berry is white. There are lots of recognition tricks to
learn. We emphasize “if you don’t know
it, don’t cut it;”
however, as here, mistakes do happen.
Following our work
session we took a short walk around the Nature Trail loop. This was the day of the first Trail Race
Festival in the Greenbelt, an event planned to be held annually, in which
runners can complete in 4 categories: a 5, 10, 25, and 50K race. For those such as myself
not metrically inclined, 50K is about 31 miles - longer than the NY
Marathon. To go that distance runners
had to make two loops in the Greenbelt, and since darkness is now coming
early runners for the second stage were required to have headlamps. The race map shows the courses threading
through almost the entire Greenbelt from Willowbrook
to High Rock Park and LaTourette. Had
we kept to our original plan of working the on the White and Blue Trails we
would have been right in the middle of the race; however, I doubt that we
would have inconvenienced anyone since our work was off the trail and even
when we were walking to and from we stepped aside whenever a runner appeared. Given all the race activity we expected to
see few animals other than runners, and that’s how it turned out. No deer or even squirrels were visible; the
entire time we were on the Nature Trail we saw only the flashy red head of a
distant red-bellied woodpecker.
In several places glossy
yellow Witches’ Butter (probably Tremella mesenterica) stuck to dead limbs like a wads of dripped
jelly caught our eye as usual, even though it had partially shriveled because
of the dry, cold conditions. Usually a
gooey looking yellow, this fungus will dry out until it is nothing more than
a thin almost amber crust on the branch it inhabits, but given a wet period
during a few warm days it will spring back to its normal jelly-like
appearance. We find it all winter
long. A little further on the trail we
found a branch with another Tremella, but this one
had the appearance of small, jelly-like brown flaps. This was Tremella
foliaceae.
We are accustomed to thinking of fungi as saprobes, decomposers of
dead tissue - in this case wood - that are a vital part in the cycle of
making the chemicals of now dead organisms available again to other living
things. Many tremellas,
however, have been shown to be parasites as well. In this case they are not parasites of
living wood; instead they are parasitic on the thin white strands of other
fungi that in turn live on wood or wood debris. These tremellas
are mushrooms which feast on other living mushrooms!
If a mushroom is
identified on a walk, invariably someone asks “is it edible?” The stock reply is that almost all
mushrooms are “edible,” but that you probably wouldn’t want to eat most of
them! A better question would be “is
it a tasty and safe edible?” The tremellas, although not specifically declared inedible in
most field guides, wouldn’t be of much interest to human foragers. One would have to go to a lot of trouble to
scape up enough to make a meal, and I don’t know of
anyone who has tried. In any case the
rule with mushrooms is if you don’t know, don’t eat. We did, however, spot some other mushrooms
that would be of interest to food foragers.
Some distance off the trail close to Rockand
Avenue stood a tree with a white blotch about four feet up the trunk. Walking closer revealed it to be a
shelf-like clump of off-white, gilled (and only slightly wrinkled!) Oyster
Mushrooms (Pleurotus ostreatus),
considered to be a prime edible, and directly opposite on the other side of
the trunk was another even more extensive growth of shelf-like gilled
mushrooms similar in appearance to the Oyster, but with a glossy brown
caps. These may have been the Late
Fall Oyster (Panellus serotinus). Both of these edible Oysters vary in color,
and are commonly found in the fall, so a harvester might take both. However, it later occurred to me that
perhaps the brown mushrooms weren’t oysters at all, but instead a similar
common fall mushroom called the Bear Lentinellus (Lentinellus ursinus). Many field guides list the Bear Lentinellus as inedible, or at least very bitter, so you
wouldn’t want to mix them up. To
settle the problem I should have collected a specimen to examine under a
magnifier. The guides say that the
gills of the Bear Lentinellus have saw-toothed
edges, whereas the edges of gills of the oyster are smooth. One can understand how the oyster mushroom
came by its name; it has somewhat the shape of a clamshell, grows smooth and
cupped, and often has a glossy white color like the interior shell lining of
an oyster. The name Bear Lentinellus however, is quite inexplicable. The common name is taken from its Latin
species name - ursinus, “bear,” - but I can’t see
anything at all bear-like about this fungus.
Close to one of the
ephemeral pools behind the Nature Center one of our walkers pointed out some
speckled twigs studded with small, fragile cones and tentative identified it
as an alder. Speckled Alders are
common shrubs of our wetlands that produce durable female cones resembling
tiny, hard pine-cones. There are no
tree-sized native Alders in our region, but we do have a few European Alder
trees which bear pinecone-like cones as do our native shrub alders. Dick Buegler
always pointed out a cluster of these trees that grow in a swampy area close
the junction of the White and co-aligned Red and Yellow trails. If we had binoculars and scanned the tops
of these trees in winter we could always spot several small cones. On our way back from the restoration site
we had passed a few Eastern White Pines (Pinus strobus) that had been planted at the corner of Rockland
and Brielle and had paused to estimate the age of the largest pine and to
examine a few of the fallen cones.
White Pines are easy to identify by their large, long fish-shaped
cones and by their needles which are bundled in clusters of five. These are our only local native conifers
whose needles are bundled in fives.
While we were there we aged the largest tree by counting the whorls of
branches ascending the trunk, every whorl representing one season’s
growth. When we later came across
these other, tiny cones, I mentioned that birch trees also produce cones, and
are as far as I knew the only deciduous trees (trees that drop their leaves
in winter, the “opposite” of evergreens) that did so.
The cones of birches,
however, are very unlike pinecones.
The finger-like scales of a pinecone are hard, protective layers
covering seeds that lie directly beneath.
If you lift the scales of a ‘ripe’ cone, you will find two bare, thin
seeds lying side-by-side under each scale.
Most of the time, however, the cones we find have opened long ago and lost
their seeds, and what we have left is just the protective, now only
decorative, husk. The tiny “scales’ of
the much smaller birch cones are not really scales, but are actually the
seeds themselves, each three-lobed seed attached one below another around a
thin central column. These seeds will
eventually fall away and be dispersed by the wind leaving these naked stalks
behind, thrusting from the bare twigs like tiny fibrous needles. After a storm the snow beneath a birch is
often peppered with these tiny, bird-in-flight shaped seeds. By now it’s probably occurred to you that
since alder cones are hard and resemble tiny pinecones, the fragile cones we
found by the pool couldn’t have come from that shrub. I stopped back a week later to look around
the same pond and discovered that the cone bearing twigs we had seen in the
shrubs had been nipped from the branches of a tall tree nearby, and the
ground around the tree was littered with speckled, cone-bearing twigs. On many twigs the seeds had fallen away
from the cones, leaving behind characteristic needle-like cores. These were the cones of a Black Birch (Betula lenta), the same birch
whose twigs we scrape in springtime to release the scent of
oil-of-wintergreen.
Returning to the Nature
Center we could not help but notice that several large trees had fallen,
victims of storms earlier in the year.
When these trees fell they uprooted large disks of roots and
soil. Standing on edge, these rooty plates always elicit comments about how shallow the
roots are that anchor these trees.
Shallow roots seem to be characteristic of many trees in our
environment; in our neighborhood they usually have no need to send down long
taproots (if that was characteristic of their type) to a deep water table or
to anchor them from frequent strong storms.
Once a tree has aged and grown so that it towers above the others it
is more exposed to the wind and vulnerable to blow-down. These numerous large fallen trees serve
notice that the woods around the Nature Center are maturing. In another hundred years or so this
landscape may display the pocked “pit
and mound” topography characteristic of old growth forests where large,
senescent trees fall, uprooting a disks of soil and leaving pits on side
toward the wind that brought them down.
When walking the woods of
the Greenbelt one notices that in many places the trees are much of the same
size. This is the appearance of young
woodlands, and almost all the woodlands on Staten Island are relatively young. During the British occupation the island
was logged almost everywhere to provide firewood and building material for
the huts of troops. In the 200 and
some years since, some of the woodlands have regenerated, but much land was
cleared instead for farms or pastures, or became woodlots that would be cut
again and again. Once cutting is
stopped or farmed land allowed to lie fallow, trees and shrubs begin to grow
back, and are at first
much of the same age.
It’s easy to spot these immature woods where the larger trees all have
the same size trunks and are all about the same height. Sometimes one can tell that a young woods has been cut before.
Often when an old woodlot has been cut and the trees have grown back,
new growth sprouts from old stumps. A
stump will often produce several sprouts that grow into a tree with multiple
trunks. These two, three and
four-trunked trees are characteristic of a cut
woodland, and you can see a lot of them in the Greenbelt. They often fall easily because each trunk
is crowded against and shaded by its clone, making each of the multiple trees
somewhat one-sided and unbalanced. As
the woods age larger trees will fall from disease or wind damage. Their fall makes openings in the canopy
where plants that require more light can flourish in sun dappled clearings
and new saplings begin to grow. These
by chance openings and new growth disturb the uniformity of a young woods and
eventually the even appearance of a new woodland is replaced by a mosaic of
trees of different sizes and ages, the giants shading out their younger
competitors while the immature trees wait for their chance in the sun.
When we left the area
where the trees had fallen we could see in the canopy that numerous branches
had been broken off by storms earlier in the year. Because these branches had broken before
Fall and hadn’t gone through the normal process of preparing for winter they
still retained brown, withered leaves and were easily visible against the
otherwise bare branches traced against the sky. This was the cue that something unfortunate
had happened to these branches. As
fall proceeds trees produce hormones - ethylene and abscisic
acid are two such - that cause the pores in the leaves to close and cause the
veins of the leaves to clog up where the stem attaches to the twig. A weak area develops there that allows the
leaves to easily separate and fall - a good thing because leaves that remain
attached catch snow and weigh down the branches so that they might easily
snap in bad weather. These branches
that had been broken early in the season didn’t go through this process, so
their brown and withered leaves stay attached. Smaller, dense clumps of brown leaves that
we see high in the trees are probably the remains of summer shelters built by
squirrels. Having been nipped off by the squirrels to make their dreys, these branches also haven’t been “winterized”, so
their leaves remain attached and make the shelters stand out when other
leaves have fallen.
There was a lot of brown
but not much green in the woods, although we did see an occasional still
green fern frond partially covered by brown leaves. A few logs lining the trail broke the brown
monotony by a display of contrasting green bands. A good “exterior designer’ was at work
here. Looking close we saw that the
dark green band on top of the logs was a lush-looking hair-cap moss, bordered
below by a paler green band of lichen, and beneath that a cracked and
checkered grey-green band of a hard, tile-like fungus called Ceramic
Parchment (Xylobolus frustulatus). All these green inhabitants of the logs
were cryptogams. There’s a neat
crossword puzzle word to hang onto, even though it’s now scientifically a
little vague. “Cryptogam” was a term
given by early botanists to all those different plants that didn’t put out a flourish
of flowers or create seeds, but instead reproduced with spores, which are
essentially invisible without magnification.
Their means of reproduction was cryptic, hidden away from the unaided
eye.
Our log bore a mixed bag
of cryptogams; there was a moss, a fungus, and a lichen. The moss and fungus produce “ordinary”
spores, but the lichen is a kind of oddball thing and reproduces in a
peculiar way. Lichens are a
combination organism, a synthesis of a fungus and an algae
growing symbiotically together, each supporting the other so that they can
thrive where neither of the partners can survive alone. The fungus gives the algae a home and
shelter from harsh environments and provides necessary minerals and other
nutrients that it extracts from the substrate it grows on; the algae produces
carbohydrates photo-synthetically as do other green plants, and this food
helps to nourish the fungus. Since the
lichen is a mix of two entirely different organisms, neither
the fungus or the algae can sexually produce another lichen. Instead lichens produce little lichen
crumbs that break off and can be blown about by wind or transported by
animals or the rush of water. Other
lichens grow special little balls of cells called soredia
(I had to look that one up) that have a durable outer coat of fungal cells
surrounding a few algae cells in the center.
Should the small pieces of lichen or the soredia
be carried away to a
suitable environment they can produce a new generation of
lichen and carry on their peculiar kind.
(Well, maybe in calling them peculiar I’m being a little
parochial. We’re told that almost half
of our own body weight is that of bacteria and other organisms that call our bodies home, and we probably can’t survive well without
some of these growing within us. We
might be as much symbiotic as the lichens.)
We like to see a variety of lichens growing in our woods because they
are generally not known to grow well in polluted environments. When we spot lichens such as the various
round green shield lichens we often see plastered on tree trunks as if they
were targets for elves we like to think the air quality in that place must be
good. Some lichens, however, such as
the very common scarlet-capped British Soldiers we often find growing in
sandy soils among mosses are very tolerant of polluted air. As always, there seem to be exceptions to
almost every generality; that’s what makes nature so confusing and
interesting.
DfR 12-10-2011.
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