Photos – Page 44 – Via Negativa

July 20, 2008 by Dave Bonta

Buck in velvet

At daybreak, the sound of hooves on gravel: a small buck accompanied at some distance by a doe meanders up the driveway, sampling the vegetation first on one side and then the other. As he rounds the bend opposite my front porch, I get a better look at the branches sprouting from his head, covered in dark-brown velvet — only four, rounded points so far, but the size and spread suggests he’ll be at least a six-point, and therefore a legal target come October.

Horns, many people call them, but the remarkable thing about antlers is that they are shed and regrow every year in a matter of months, unlike true horns, which are permanent. The energetic cost to the animal must be enormous. A rack, they call it, as if it were designed by God or evolution as a place to hang coats or display trophies. But this most prized of natural artifacts is itself a trophy — to hunters, and perhaps also to the deer, who holds his head so differently from a doe.

It’s just light enough to let me observe what he eats as he approaches the house:

the leaves of several goldenrod stalks, starting at the bottom and working toward the top;
a couple twigs of a multiflora rose bush, one of two beside the driveway that are as compactly rounded as if they’d been kept pruned by hedge-trimmers;
half of a large, compound leaf of a black walnut seedling the same age as the deer;
one stalk of wild garlic, starting with the tight fist of baby cloves at the top;
several mouthfuls of orchard grass;
the tip of a leaf of bracken fern;
some brome grass in front of the stone wall that borders my garden.

He’s near enough now that that I can hear the chewing and the smacking of lips. He crosses the road, lured by the sight of black raspberry leaves, and starts working on the end of the very cane that hosts a paper hornets’ nest at its base. A moment later, the anters jerk upright, and he bats at his shoulder with a hind leg. Then with one leap he clears the drainage ditch and lands among the cattails, twisting and rearing like a wild mustang with a bronco-buster on its back. A few seconds of that and he prances over to the woods’ edge, head still held high, to join what I imagine must be his sister — last year’s twins. If any hornets are still following him, he doesn’t show it, and neither does she. Their association is safe for at least a little longer from nature’s maddening sting.

July 18, 2008 by Dave Bonta

Hat season

Ah, summer — time of berry picking, vine-ripened tomatoes, corn on the cob, and big ol’ floppy hats. Because it’s also high noon for deerflies, mosquitoes, no-see-ums, and, well, high noon. (There’s a video that goes along with this shot, by the way. Catch it at my mother’s blog.)

I’ll admit, though, I was a little shocked when my dad traded in his usual stylin’ John Deere cap for a shapeless straw hat he found in the closet. “The brim goes all the way around with this kind of hat,” he marveled. “The mosquitoes don’t come under it.”

I’m not entirely sure the hat was made for men, but whatever. My dad is nothing if not secure in his masculinity.

It might be that Ma Nature is sending us subliminal messages, though. Between the Indian pipes and the mushrooms, hat-like things have been popping up all over the place. I watched gnats swarming around a rotting amanita yesterday: they crawled all over the top-side, but I didn’t see a single one venture beneath the brim.

Which got me to thinking there might be a big evolutionary advantage to this sort of behavior, because the underside of a mushroom, or any other projecting shelf, would be an ideal place for a spider to lurk. Maybe to the Diptera, it’s not that mushrooms are hats; hats are great big mushrooms.

Just, you know, a theory.

When your hat is your home, you take it off at your peril. Things will never again seem as safe and dark and quiet as they did under a hat. Mosquitoes will come and sing in your ears, and not only because they’re looking for a blood meal. They get a darn good echo in there. Ears, being put on sideways, probably don’t look like hiding places for spiders in most cases.

But think of the way an ear is shaped. Maybe, just maybe, the mosquitoes too are looking for a hat.

July 5, 2008 by Dave Bonta

Richweed

If you can’t see the slideshow, or if you’re on dial-up, go here.

I found the cicada struggling to mount a leaf, clawing feebly at the smooth surface. It had somehow survived the avian gauntlet, but death would come soon one way or another. Elsewhere in the patch, stray wings of less fortunate cicadas were scattered about, looking very much like transparent maple keys.

Few plants offer as many opportunites for arthropod watching when they aren’t in bloom as the large-leaved and aromatic Collinsonia canadensis. I’ve always referred to this plant simply as “horsebalm,” but apparently that name has been applied to other members of the Collinsonia genus as well, along with “stoneroot”; I should be calling it Canada horsebalm to be more specific, or better yet, richweed. Though prized by herbalists, and once an important medicine to the Iroquois and Cherokee, for us it’s mostly just a nice, citronella-scented plant that’s fun to point out to tour groups on hikes up the hollow — we always like to add an olofactory element to our tours. In another month or so it’ll send up spikes of yellow flowers, but why is it so popular with the six- and eight-legged crowd now? From what I could see, simply because its large, horizontal leaves help with thermoregulation: where they intersect with short-lived sunbeams in the otherwise cool forest, they’re great places to sunbathe.

Needless to say, this is a (semi-) macro photographer’s dream. Most of the woods is simply too dark to take photos without a tripod; I’m pretty much limited to snapping what’s in the sun. And since it was a cool morning, the insects were in no hurry to move on. But as usual, my attention was drawn as much to the stage set as to the actors: the shifting patterns of sun and shade, the color and texture of the leaves.

I wasn’t the only one drawn by the concentration of insect life. A funnel spider had set up shop, curling a leaf into a lemon-fresh lair of death. A~~n assassin bug~~ squash bug* seemed less interested in stalking prey than in feeding on a bird dropping. When I came in too close with the lens, it circled to the other side of its prize and assumed that pugilistic pose so typical of its kind. And a pair of harvestmen — or a harvestman and a harvestwoman, as the case may be — seemed most interested in each other. For the entire half-hour I was there, they stood face-to-face, barely moving except for their long front legs, which met and circled like foils in the world’s slowest fencing match.

I think I’ll be calling it richweed from now on.

*See comment by Rebecca Clayton below.

Flickr slideshow created following the very helpful instructions of Paul Stamatiou.

July 3, 2008 by Dave Bonta

Paths of infection

In a few more years, the path in this picture will be two centuries old. That’s fifty years older than any of the buildings in the hollow. They’re the healed remains of the roads the colliers built when they first clearcut the mountain, with results that must have been catastrophic for the hollow: floods, fire, massive loss of topsoil. But now, chances are if you come to visit in any other season than winter, our moss-covered trails are one of the things you’ll most remember about the place. They’re beautiful. In spring and summer, before the leaves fall and turn every step into a loud whisper, it’s possible to stalk through the forest as quietly as a burglar.

I always confuse the path with the destination. Don’t you? I start out intending to go somewhere, but then something catches my eye and I slow down for a closer look. Then I notice more. An hour hour later, I’ve only made it half a mile from the house.

Nothing draws the attention quite like someone or something with a disfiguring disease. Whatever is decimating the mountain laurel here begins with colorful eyespots: brown rimmed with red and yellow, like targets in reverse. With certain kinds of sickness, yes — the leading edge of infection is marked by unnatural brightness. That fever glow.

I found a black gum tree with a bad case of warts. Each wart is a hermit’s cell for an Eriophyid mite, a microscopic, two-legged relative of spiders. It goes through a mere two larval instars, and manages to have sex while maintaining its immaculate separation from others of its kind:

Mites do not mate with each other; sacs that the male leaves lying around on the leaf surface fertilize the female as she walks around.

Freedom from sexual contact can be liberating. Some species of Eriophyid mites alternate all-male generations with all-female generations. Very little is known about them beyond these basic facts. Some 90 percent of Eriophyidae have yet to be named and classified by taxonomists, so I suppose chances are good that this is one of them.

For the tree, the galls aren’t the sickness, they’re the treatment. The tree would say, with some justification, that each mite is walled in to keep it from spreading. But the mite, like thousands of other gall-making arthropods, is in fact practicing a kind of ju-jitsu, using the tree’s defenses against itself. The feeding chambers are not only ideal for solitary contemplation, if such be the bipedal mite’s inclination, but keep out most predators, as well.

After they attain adulthood, the Eriophyidae abandon their chambers. This is the time when accidental sex may occur. Many of them also take to the wind and float for miles, like the Daoist sages of legend. Some of them, no doubt, end up in my lungs.

This black gum bears the scars of somewhat larger animals — bears and humans. When I painted a trail blaze on it seven years ago, I can’t remember seeing the other marks there, but judging from the depth of scar tissue, bears have been carving up this tree for some time. Though they much prefer electric and telephone poles to communicate their “Kilroy was here”-type messages to other bears, any conspicuous tree, living or dead, will do. For hikers, this is a useful reminder that they aren’t the only ones using the trails. For bears, it is perhaps a gratifying reminder of the fact that our paint marks are no match for their claw marks. Bears often destroy human-made things left in the woods — it’s as if they regard us as some kind of enemy.

For the tree, unless and until the trunk is completely girdled, none of this is a real impediment to continued growth and prosperity. Black gum trees are masters at walling off wounds with thick scar tissue. They almost all rot out at an early age, making them impossible to date by ring counts. But the outer shell of a mature black gum is hard as iron.

White pines fight disease with tars, which can sometimes keep them standing after death for as long or longer than they stood as living trees. A century after the forest fire, a short-lived path that the flames took up the trunk of a pine tree is still marked with charcoal and a livid blaze.

June 27, 2008 by Dave Bonta

A non-plague of non-locusts

The locusts are, it must be said, a bit of a plague on the locusts. The males call “Pha-roah! Pha-roah!” in a slow southern drawl while the females plunge their scimitar-shaped ovipositors into the thorny twigs, sometimes so deep that they break. All along the top edge of the field, the black locusts are acquiring a pruned and chastened look, as if they were the victims of some very localized storm.

Of course, 17-year “locusts” are really cicadas (see Brood XIV). According to some sources, when early European settlers first encountered periodical cicadas in eastern North America, the only parallel they could think of for such an extreme insect outbreak was the plague of locusts in the Bible, so “locusts” they became — despite the fact that, as members of the order Homoptera, they could scarcely be more distantly related to true locusts, which are grasshoppers, Orthoptera. According to the Locust entry in the Wikipedia, however, the conflation goes much further back, to “the Vulgar Latin locusta, which was originally used to refer to various types of crustaceans and insects.” The English essayist Thomas Browne was bemoaning the confusion between locusts and old-world cicadas as early as the 17th century. And obviously the popular description of the call of Magicicada septendecim as “Pharoah” shows the unabated influence of Exodus 10:4-15.

However, it would be a great exaggeration to say of these “locusts” that “they covered the face of the whole earth, so that the land was darkened; and they did eat every herb of the land, and all the fruit of the trees which the hail had left: and there remained not any green thing in the trees, or in the herbs of the field, through all the land.” Here’s what the folks at Cicada Mania say:

Question: Will the cicadas kill my trees, shrubs and flowers?
Answer: Possibly. Cicadas don’t kill flowers and shouldn’t damage shrubs, but they can do damage to young, wimpy trees like ornamentals. If you have wimpy little trees, you can net them to keep the cicadas off. Tree species that aren’t native to North America won’t fare as well as native species. Trees that lose a lot of branches typically revive after a year or two, but they will be ugly in the mean time. Cicadas actually are a benefit to trees, as they destroy the weaker branches. Please don’t use pesticides — you’ll destroy the good bugs as well as the “nuisance” bugs, and ultimately do your garden and the environment a huge disfavor.

Of course, as larvae, cicadas do subsist on tree sap, but given that cicadas and deciduous trees have evolved together, I doubt that they do much to weaken the trees. Though the science is inconclusive, it’s likely that their extensive tunneling benefits the trees by aerating the soil, and possibly by creating macropores for new roots and fungal mycelia. An AP article quotes a Dr. Frank Hale from the University of Tennessee:

The holes from which they emerge aerate the soil around the tree roots, Hale said. The millions of decaying cicada bodies supply nitrogen and other nutrients, which rain washes down the holes to the tree roots.

However, a Penn State Ag School publication for orchardists assumes the worst, and considering the unique stresses on heavily pruned and sprayed trees in monocultural plantations, it may well be on-target with its recommendation to prevent egg-laying at all costs. It also emphasizes netting if feasible, and mentions the harmful effects of pesticides on beneficial insects.

Do the various Magicicada species vary in their arboreal preferences? I’ve mentioned black locusts as a favorite for swarming and egg-laying activity (see my video at the Plummer’s Hollow blog), but I suspect that’s largely because of their location in the field-forest ecotone. The cicadas here do show an affinity for forest edges and openings, regardless of where they originally emerged. I don’t know if the fact that locust trees are nitrogen-fixing legumes makes them any more attractive as adoptive mothers to cicada larvae. We have noticed relatively few cicadas in the black walnuts that surround the main house, which might seem logical given the toxicity of walnut roots to many other plants, but it seems that if we had the rarer third species, Magicicada septendecula, that might not be the case:

Within the same brood, the three species are always perfectly synchronized, but they are separated microspatially by having different habitats within the same woodland. Magicicada septendecula prefers ovipositing in hickories and walnuts, and emerges in higher proportions under those trees than under comparable oaks. Both M. septendecim [the “Pharoah” species] and M. septendecula occur together in upland woods, but septendecim exhibits much less host specificity than septendecula. The latter species is much rarer than septendecim; it can usually be heard chorusing in local patches within a woods occupied by septendecim. Magicicada cassini is a species of floodplain woods, and characteristically can be seen to replace septendecim and septendecula as one moves down a wooded slope leading to a stream. Over much of the eastern United States, however, the original forest has been extensively disturbed. Periodical cicadas survive and reproduce surprisingly well in cutover, scrubby second growth. Tree species characteristic of floodplains, like American elm, are often a component of upland second growth, and, especially in such situations, cassini, septendecim, and septendecula become intermixed though they remain reproductively isolated. The present lack of microspatial separation in many situations, then, is an artifact of human disturbance.
—Henry S. Dybas and Monte Lloyd, “The Habitats of 17-Year Periodical Cicadas (Homoptera: Cicadidae: Magicicada Spp.),” Ecological Monographs, Vol. 44, No. 3 (Summer, 1974)

That might explain why the M. cassini cicadas are so much louder and more numerous around Canoe Creek State Park, much of which is floodplain or early-succession second growth. At our annual Audubon Society picnic last week, they were nearly deafening. In fact, a friend just told me that the dog-day cicadas are usually very numerous there, too — and regardless of the species, they make excellent fish bait, he said. Hardly the stuff of plagues.
__________

Today is the deadline to submit links to the next Festival of the Trees. Details are here.

June 21, 2008 by Dave Bonta

The shortest night

The morning after the summer solstice, which arrived just before 8:00 p.m. here, the garlic tops have each coiled another half-turn. Irises that were once blue dangle curled brown locks and raise flags of surrender, milky as a blind man’s eyes. It’s chilly. I grab my hooded sweatshirt off the doorknob and stand staring for a moment at my reflection in the bald brass.

A 100-foot section of the mowed path leading from the garage into the woods is bejeweled with cicada wings, hundreds upon hundreds of them, covered with dew and glinting in the morning sun. What brought them there?

They had to have been brought: it’s not an area where either the emergence or the courtship of the 17-year cicadas have been particularly intense, or indeed noticeable. There are no overhanging branches from which birds might have discarded the wings as they ate — in fact, the wings peter out as soon as small trees begin to line the trail.

I suspect raccoons. What else could it be? I can picture them gathering there in the light of the just-past-full moon, squatting companionably as they pull the wings off their squirming victims and chew, chew, chew.

June 16, 2008March 6, 2014 by Dave Bonta

Father’s Day surprises

Father’s Day dawned clear and cool. After making an appointment with my dad to cut his hair later in the morning, I took my camera for a walk. Along the Road to the Far Field, in one of the large clearings created by the icestorm of 2005, I surprised a chipmunk next to a fruiting red elderberry bush. It froze when I hove into view, and the bright sun might’ve helped dazzle it a little as I inched closer for a clear shot through the brambles. Ecologists who study the effects of deer on forest health consider red elderberry a good indicator of low browse pressure, and we’ve been happy to watch its spread through moister portions of the property in recent years, thanks to the abundant patience and excellent marksmanship of our hunter friends. As this photo graphically demonstrates, lower deer numbers are good news not just for plants, but for other animals, too.

I made my way to the thicket below the Far Field, where I knew the dense carpet of mayapples would be entering their autumn now as their fruits approached maturity. First they break out in a rash of yellow spots. Then larger areas of brown appear around their edges, turning them thin and brittle as old newspaper.

A few paces into the woods, in a patch of shade too dark to permit a decent photo without a tripod, I found a dense network of slime on the ground, as if a snail had been trying to weave a spider web. Then as I circled the field on a path I’d mowed just a few days earlier, I found two orange and olive tentacles poking out of the ground, foul-smelling and rubbery to the touch, about four inches long and half an inch in diameter at the base. They were in bright sunlight, but still I managed to screw up and didn’t get a single clear photo.

This was the best I could do. It reminded me of a web comic I’d seen recently, in which an apparently fortuitous discovery has unpleasant repercussions. They turned out to be stinkhorns of the Mutinus genus, which lack the bulbous heads of their Phallus cousins: probably Mutinus elegans.

Many of the metaphors we use to try and come to grips with the inherent weirdness of nature aren’t terribly accurate, but the association of stinkhorns with human sex organs is right on target. In Mr. Bloomfield’s Orchard: the Mysterious World of Mushrooms, Molds, and Mycologists, author Nicholas P. Money writes,

Most of the volume of the erect fruiting body is air. But mechanically speaking, the stinkhorn is comparable with the mammalian penis because both erections are maintained by pressurized fluid rather than a column of solid tissue. The penis contains flattened reservoirs that become engorged with blood, while the tissue of the stinkhorn receptacle is built to tear apart to make a honeycomb supported by pressurized water within its hyphae.

One major difference, of course, is that mammalian erections don’t bulge with fertile spores or smell like rotting corpses, and aren’t designed to be eaten by flies and slugs, which will plant the seeds of a new generation of stinkhorns in their excrement.

That wasn’t the only place where bizarre reproductive rituals were taking place. All along the top edge of the field, the 17-year cicadas were singing and flying, clicking and crawling through the scrubby locust trees — appropriately enough, given their alternate common name, “17-year locusts.” I shot a video and posted it to the Plummer’s Hollow site, in an entry headlined “Cicada courtship in full swing.” I like the way biologists persist in referring to mating behavior as courtship: such an old-fashioned word, conjuring up visions of hay rides, shucking bees, and minuets in the parlor.

Ebony Jewelwing, from the Undiscovery Channel.

I was surprised to see several male ebony jewelwing damselflies on the ridgetop, half a mile at least from the nearest stream. They were, however, engaged in classic jewelwing flit-and-pause behavior. I like the video not just for the jewelwing — which is out-of-focus part of the time — but the soundtrack, which features a wood thrush, a scarlet tanager, a pileated woodpecker, chipmunks, and a train whistle, all set against a background surf of cicadas. (This was a couple hundred yards in from the edge of the field.)

In Indian musical theory, I’m told, the drone note symbolizes the inescapable horizon. Over the past week, the cicada chorus has contributed an almost constant, high-pitched drone as a backdrop to other elements of the soundscape. And from my front porch, first thing in the morning, that drone does literally emanate from the eastern horizon: the crest of Laurel Ridge, where the sun first strikes. By mid-morning, though, the cicada choruses become more dispersed.

Speaking of Laurel Ridge, the mountain laurel was at its height of bloom yesterday, meaning that no more blossoms remained in bud — and that the earliest blossoms were already on the ground. As decimated as the laurel has been by winter-kill and diseases over the past six or seven years, we didn’t expect to see the woods turned white with their blossoms ever again, but this year comes close to the way it used to be every other year, back in the 90s and before. 2008 has been a remarkable year for flowering shrubs and trees of every description, from shadbush and red maple to wild azalea and tulip poplar.

When I got back to the house, I dug out my barber’s kit, we found an old sheet, and I had Dad sit on the veranda for his haircut. He’s slowly healing from surgery to remove a tumor on his lower spine last month, which involved slicing into the dura mater and coming right up against a cluster of nerves. Enough pain and numbness remain to make a trip to the barbershop seem like a daunting prospect.

The hair was thin and didn’t take long to cut — a scattering of tufts on the concrete floor. A half hour later, when Dad came out on the veranda again for some reason, he saw them there and couldn’t figure out what they were for a second. “That can’t be my hair!” he said. It had been silver for what seemed like forever, I guess, but now it was undeniably white, as white as snow. In a morning full of surprises, the passing of time was still the most surprising thing of all. I’m sure the 17-year cicadas would agree.

June 9, 2008 by Dave Bonta

Lines for a June heat wave

Click to see larger

A half-grown groundhog —
“Wait while I get the camera,” I say,
& it does.

Recognized by its glide,
the first monarch butterfly
back from the south.

In the air-conditioned mall,
the plastic flowers are safe
from the blistering heat.

Drinking from a tap
in the base of an old elm,
a Penn State squirrel.

I run into someone
I first met 17 years ago,
in cicada time.

So good, I don’t want to finish it:
fresh strawberries sliced
into stewed rhubarb.

Inside the package
stamped “Royal Mail,”
a book of small stones.

Driving the tractor into the woods,
mountain laurel blooming
above the roar.

Back from mowing,
I find a ground beetle trapped
in the kitchen sink.

A game in a dream:
no one knows the rules, or how to win.
I wake to heat lightning.

*
For another view of the half-grown groundhog, see here.

May 31, 2008 by Dave Bonta

None dwell in their tents

Let their habitation be desolate; and let none dwell in their tents.
Psalm 69:25 (KJV)

Eastern tent caterpillars (Malacosoma americanum) are a common sight this time of year, especially in their last instar, after they abandon their tents. They stray onto the porches and wander over the furniture, looking for protected places in which to pupate. On a visit this past Monday, my three-year-old niece Elanor decided that they were cute — not typically my own reaction — and began petting them, prompting the caterpillars to arch their heads back like housecats. Yesterday afternoon, I watched one crawling up the neck and across the face of a box turtle, which merely shut one eye while the caterpillar took its measure.

The tents began appearing at the end of April in unusual numbers, especially on black cherry trees, which are the favorite food source for tent caterpillars and occur in unnatural abundance across Pennsylvania due to 150 years of clearcut logging practices and the reversion of old fields and pastures. Black cherry is a common first-succession tree species in many forest types, and thanks in part to its relative unpalatability to white-tailed deer, it can form almost pure stands in many areas that would have formerly hosted oak-hickory, beech-hemlock, or mixed deciduous forests. Here in Plummer’s Hollow, many of our southeast-facing slopes are dominated by black cherry stands, and I figured they’d be completely defoliated by this time.

Instead, Sapsucker Ridge is white with blossoms, filling the air with an ambrosial scent. One finds only a few black cherries as badly defoliated as the one in the second photo; the tree above is more typical. Though dotted with tents, only scattered branches have actually been stripped of their leaves.

A closer look reveals that most of these tents are filled with dead caterpillars. The few still alive twitch spasmodically. What happened? I’d guess that the unusually cold, wet weather over the past few weeks is at fault. Nighttime temperature routinely dropped into the low 40s this month, and sometimes even into the high 30s; daytime temperatures rarely exceeded the mid-50s; and rain was almost constant for the first three weeks of the month. Not only would the cold have shut down their temperature-sensitive digestive systems for prolonged periods, but the rain would have kept them confined to their silken tents, and the two together would’ve made them much more susceptible to starvation and disease. According to the Wikipedia article on tent caterpillars,

The tent is constructed at a site that intercepts the early morning sun. The position of the tent is critical because the caterpillars must bask in the sun to elevate their temperatures above the cool ambient temperatures that occur in the early spring. Studies have shown that when the body temperature of a caterpillar is less than about 15 °C [59 °F], digestion cannot occur. The tent consists of discrete layers of silk separated by gaps and the temperature in these compartments varies markedly. Caterpillars can adjust their body temperatures by moving from one compartment to another. On cool mornings they typically rest in a tight aggregate just under a sunlit surface of the tent. … Later on in the spring, temperatures may become excessive at mid day and the caterpillars may retreat to the shaded outside surface of the tent to cool down.

Entymologist Vincent G. Dethier’s wonderful and evocative classic, The World of the Tent-Makers: A Natural History of the Eastern Tent Caterpillar (University of Massachusetts Press, 1980) describes in Chaper 13 (appropriately enough) the battery of predators and diseases that keep this native insect in check. He details the spread of a deadly virus from colony to colony, then adds:

As if that were not enough the unusually wet late spring had been kind to molds, mildews, smuts, blasts, and bacteria. A particularly virulent spore-forming species of bacterium struck many of the colonies. … The enormous population of tent caterpillars had been cropped by weather, starvation, ants, bugs, parasites, fungi, viruses, bacteria, and misadventure in general. It had been a particularly trying year. Summer had hardly begun and the die had already been cast for the year to come. There would be fewer moths, fewer egg masses, and fewer colonies of the next generation.

So a spring that spells bad news for many farmers is good news for the wood products industry, which relies heavily on black cherry in Pennsylvania. Unlike fall webworms, which come too late in the season to have much of an impact on the trees they defoliate, tent caterpillars can greatly stress the trees they defoliate during their periodic outbreaks.

As global climate change plays hob with our weather patterns, it will be interesting to watch the effects on insect outbreaks, and over the long term, on forest succession. For example, if black cherries continue to predominate as many foresters would like, more-frequent icestorms would have a much greater impact than they would if less brittle species such as red oaks and tulip poplars took their place. Warm winters are said to promote the spread of pest insects, but what about warm winters followed by cold springs? I’d heard that the state was due for some pretty large gypsy moth outbreaks this summer as well, but here in Plummer’s Hollow, at least, their caterpillars are few and far between.

Cross-posted to the Plummer’s Hollow blog.

May 20, 2008September 9, 2013 by Dave Bonta