August is mostly hot and humid, but every year there are more and more mosquitoes. Many people blamed the excessive rain in the spring and summer of 2018 for the massive numbers of mosquitoes and black flies. It was almost as if we were living in the North Woods.
Our vernal ponds on top of Sapsucker Ridge became permanent ponds that provided adequate breeding places for mosquitoes once the hundreds of wood frog tadpoles metamorphosed and leaped away into the woods in late May and early June.
Other conservationists I talked with agreed that even the smallest vernal ponds didn’t dry up in late spring as usual. But while I agreed that our record-breaking wet year was partially responsible for the large mosquito population, I didn’t think that was the whole story.
The invasive white-nose syndrome, a fungal disease brought accidentally to a New York state cave in 2007 by Europeans, has killed 99% of our little brown bats in a few years. Previously we could sit outside on our veranda at dusk and watch as the bats flew overhead eating mosquitoes. Now that they are gone and despite the best efforts of biologists throughout the United States, all cave bat species will not recover to anywhere near their previous numbers for a century or more. Consequently, mosquitoes are so bad here that sitting outside on our veranda in the evening is only a fond memory.
The country church at Canoe Creek State Park that once housed a nursery colony of as many as 22,642 mostly little brown bats, now has 250 mostly big brown bats that have not been as susceptible to the disease.
A Blair County mine, gated by the Pennsylvania Game Commission, held 30,000 or more little brown bats before 2010, when white-nose syndrome was first detected there, but in 2015 it had a mere 54 of them, in 2018 it had 290, and last winter 150, according to PGC biologist Greg Turner.
“Each bat eats nearly one million insects a year,” Turner says in an email. And little brown bats, once Pennsylvania’s most common bat species, specializes in mosquitoes, according to Melvin Tuttle, founder of Bat Conservation International.
Many folks believe that nature can easily recover from such losses, but while killing coyotes, for instance, will encourage them to produce more offspring, a little brown bat female can produce only one pup a year.
Our plague of mosquitoes may also be carrying West Nile virus because we used to have a good population of ruffed grouse. Last spring, although my son Dave and I monitored all the places where we used to hear drumming in the spring on our 648 acres, we heard none. The days of being detained while driving down our wooded mountain road by displaying ruffed grouse or being stopped on our Far Field Road or First Field Trail by distressed females as their little, pale yellow, powder-puff chicks ran off and hid are over.
Insects from abroad are also wreaking havoc on our hemlock and ash trees. Although the hemlocks are dying a slow death instead of a fast one, probably because of occasional below zero winter temperatures that kill off many hemlock woolly adelgids, our ash trees have succumbed quickly to the emerald ash borers. Everywhere I walk on our land I see dead ashes where only a few years ago they were thriving and attracting songbirds, wild turkeys and squirrels to their winged seeds.
As if all the invasive insects and diseases aren’t enough to keep scientists busy, we are faced with an onslaught of invasive plants that are overwhelming our fields and forests. Every spring I pull out as many garlic mustard plants, a European invasive, from our primary forest as possible especially from our mile-long road bank that harbors a wide variety of native wildflowers and shrubs.
Japanese stiltgrass came in with the logging trucks on our neighbor’s adjoining property (now ours), and we didn’t realize the danger of this annual grass from East Asia, also known as Asian stiltgrass and Chinese packing grass. In fact, the dried grass filled with seeds was accidentally introduced in packing material for Chinese porcelain in Tennessee back in 1919.This one to two-foot tall weed forms a dense mat that smothers any small plants or seedlings in open areas in our forest and fields.
The 120-acre logged area we purchased in 1992 has since filled up with invasives including Japanese or red barberry, a Japanese native shrub introduced in the late 1800s in the United States as an ornamental. It forms dense stands that shade out and displace native species. Not only is it two to six feet high, but it can reach that width as well. In addition to spreading in the logged land, it also managed to invade our three-acre deer exclosure when a large maple tree came down in a wind storm, creating an opening in this section of our forest.
Yet in a 40-acre section of forest on Sapsucker Ridge that came down in an ice storm, not one barberry germinated. As I walk our trails, observing where various invasives take hold, I often puzzle about why this spot and not that one and know that the answers are complex as are most puzzles in the natural world.
Last September, while walking Butterfly Loop around the edge of our First Field, also hedged with barberry below the wooded ridge, I noticed iridescent blue fruit growing in terminal clusters from a vine hanging on a black locust tree. It had triangular-shaped leaves and downward curving spines on stems and leaf veins. To my horror, I identified it as mile-a-minute, still another invasive from East Asia.
Mile-a-minute grows in moist, sunny locations along road sites, rivers and stream banks, powerline right-of-ways and disturbed forest sites. I immediately ripped out all the plants I saw at the top edge of First Field and quickly discovered that its vine-like stems grow up to 20 feet long.
The next day, when I walked Greenbrier Trail through the logged area, I saw acres of mile-a-minute covering many barberry shrubs like shrouds. An invasive on top of an invasive. That was a first for me. I started yanking it out, but after an hour I gave up. There was far too much of it for me to remove. If only I had noticed it sooner.
With that lesson in mind, I finally identified the beautiful shrubs with lovely, white, four-petaled, two-inch-wide flowers at the base of our mountain as jetbead. Again from East Asia and again introduced as an ornamental to the United States in 1866. Named for their clusters of red, bead-like fruits that turn ebony, they create a thick shrub layer in forests that displace native shrubs and shade out understory species, such as tree seedlings.
I started pulling out the shrubs and quickly realized that there were more than I could handle. Our caretakers have taken over the job and have nearly eradicated it.
To reach our road, we cross a county bridge over the Little Juniata River and drive a couple hundred feet on a gravel township road where folks often dump cuttings from their gardens. That small section of roadside harbors numerous invasives such as English ivy and greater celandine. The latter plant has bright yellow, poppy-like flowers in May and June. Also known as “rock poppy” and “devil’s milk,” it comes from Europe and Asia and can outcompete native plants.
A friend had warned me years before that it was invasive so when I found several dozen plants growing on the Far Field Road bank, more than two miles from the colony along the township road, I regretfully yanked every plant out by the roots. So far, none have returned. A small victory indeed when stacked up against the dozens of invasive plants, insects, and diseases plaguing our fields and forests.
I never thought, at my advanced age, that I would see so many permanent changes on our land, primarily due to foreign trade and travel. Furthermore, I see little hope in eradicating these plagues here during my lifetime.
One day, in late August, I walk over to Greenbrier Trail and hear a singing hooded warbler. Then I notice a native Hercules’ club in green berry. I drop down to Ten Springs Trail where I find the trail bank is filling in with native maple-leaf viburnum shrubs and white wood asters. Walking back up our road, I discover a blooming turtlehead beside the stream. There is still much native beauty and wildlife on our mountain and I am grateful.