A Northwoods Almanac for 8/20/21
Bird Migration!
Fall migration has begun, a statement I’m always sad to make. Radar in Duluth on 8/12 showed strong southbound bird activity, and during the rest of the week, conditions with westerly and northerly winds were also excellent for more birds on the move. Among the early migrants this time of year are shorebirds, warblers, flycatchers, orioles, grosbeaks, and bobolinks. So, new species from further north may be showing up on any given day now, while we have no choice but to say goodbye to many of our local nesting birds. The young are full-grown, fledged, well-fed, and ready to fly long distances on their first incredible voyages across night skies to places they’ve never seen.
From 2013 to 2017 the Cornell Lab of Ornithology summarized migration data from 143 weather stations to provide the first large-scale counts of migratory bird activity across the United States. They estimated that an average of 4 billion birds pass from Canada across the northern border of the U.S. in autumn, while an average of 4.7 billion birds leave the U.S. for Mexico and points south each fall. As ornithologist Scott Weidensaul writes, “migration stitches continents together.”
Sightings – Double-crested cormorant, Blowdown photo, Indian pip
On 8/12, Peggy Allen reported seeing a juvenile double crested cormorant on a little pond right next to Howard Young Medical Center in Woodruff. She noted that it had been there for four dayss, swimming, fishing and hanging around with the ducks.
Peggy’s sighting is really unusual for our area. While cormorants are common on large bodies of water like Lake Michigan and Lake Superior, they’re much less common on small inland lakes, and relatively rare on little ponds like Peggy described.
Jill Joswiak sent me a photo of a large tip-up mound from a blowdown that occurred several weeks ago on the Franklin Lake Nature Trail east of Eagle River. Her friend Nicki Paulson is standing in front of it for perspective. The photo amply illustrates how shallow-rooted many trees are in the Northwoods.
On 8/4, Mary Madsen in Presque Isle sent me photos of Indian pipe flowers, now called corpse plant flowers (Monotropa uniflora), growing in the woods along her driveway. Many years ago I’d written about these as saprophytic plants, saying they lived off decaying organic matter. Well, in recent years, this plant has been found to be a parasite, stealing nutrients from mycorrhizal fungi in the soil. Mycorrhizal fungi live symbiotically with various tree species, trading water and minerals that the fungi absorb from the soil for nutrients the trees supply them via their photosynthesis. The Indian pipes tap into this mutually beneficial exchange, grabbing nutrients from the mycorrhizal fungi without any reciprocity.
Corpse plants are a waxy white flowering plant bereft of chlorophyll, and thus can’t photosynthesize on their own, leaving them to find a way to pilfer nutrients from other sources. Plants that feed on mycorrhizal fungi are call mycotrophs, and include species like spotted coralroot, pinesap, and beech-drops.
Once these pure white flowers are pollinated by bumblebees, they turn upwards and begin to turn black, eventually developing a dry fruiting capsule that holds tiny sawdust-like seeds. Apparently Emily Dickinson loved corpse plants, because one appears on the cover of her first book of poetry.
Germain Hemlocks SNA and Frog Lake and Pines SNA
Over the weekend, Mary and I led four hikes for the Natural Resources Foundation in the Germain Hemlocks State Natural Area and the Frog Lake and Pines State Natural Area. Both are quite different from one another primarily because of the soil where they occur. Germain Hemlocks SNA is 88-acres atop sandy loam soil, and thus supports a beautiful old-growth hemlock-hardwood forest comprised of Eastern hemlocks and sugar maples, with some yellow birches, basswoods, and red oaks. The site runs between three lakes and contains attributes one looks for in an old-growth stand, like large standing snags, an abundance of coarse woody debris covering the forest floor, and some scattered reproduction of hemlock. The natural area is named in honor of Clifford E. Germain, the first ecologist and coordinator hired in 1966 to manage Wisconsin’s State Natural Areas program. His vision helped grow the SNA program from 48 sites and 10,000 acres to 211 sites and over 50,000 acres during his 37-year tenure.
Frog Lake and Pines SNA, on the other hand, is situated upon very sandy soil, which supports an old-growth forest dominated by red and white pines, and also includes 42-acre Frog Lake, an undisturbed wilderness lake. About one-quarter of the shoreline around the lake consists primarily of mature to old red and white pines, a few of which are 36 inches or more in diameter. The 1,290-acre SNA lies within the 6,265-acre Manitowish River Wild Resource Area, formerly known as the Manitowish River Wilderness. Wetlands cover over two- thirds of the wilderness, with islands of pine scattered along the shoreline and inland. The Manitowish River, a state-designated “exceptional” river, meanders slowly for 16 miles through the SNA from the Hwy. 47 bridge downstream to the Turtle-Flambeau Flowage.
People from all over the state traveled to the Northwoods for the opportunity to walk in these sites, and they reveled in not only their beauty, but in their ecological stories. Because the dense canopy of hemlocks dominate the Germain site, the area is in perpetual shade, and the understory is typically damp and windless. Thus, fires are typically very uncommon here, and when the forest is disturbed in some manner by nature, it’s by a windstorm blowing down some trees.
Frog Lake, being dominated by pines, is much more wide open to the sun, and thus is a drier site far more susceptible to fires. In fact, a fire ecologist did a study of the tree rings from one old red pine in the stand, and found that the tree began life in 1805, and showed fire scars in 1833, 1846, 1855, 1864, 1877, 1895, 1909, and 1910.
So, we talked with our groups about the differences in these plants communities, each community being adapted to natural disturbances caused either predominately by wind or by fire. For instance, common understory herbaceous plants in a dry pine forest are trailing arbutus, hepatica, barren strawberry, and wintergreen. In a moister hemlock forest, common herbaceous plants include wild sarsaparilla, rosy twisted-stalk, large-flowered bellwort, and shinleaf. Some plants overlap like partridgeberry and Canada mayflower, but they’re the exception, not the rule.
Different plant communities, of course, support different bird species, so dominant birds in a big pine stand include blue-headed vireos and pine warblers, while a hemlock stand has far more black-throated green warblers, yellow-rump warblers, winter wrens, and Blackburnian warblers.
Beauty, however, was the overarching element found in both sites. Pines, as John Eastman wrote, are “the larynx of the wind”, whereas the wind in hemlocks, as Donald Culross Peattie wrote, is “no roaring like the pine’s, no keening like the spruce’s. The hemlock whistles softly to itself. It raises its long, limber boughs and lets them drop again with a sigh, not sorrowful, but letting fall tranquility upon us.”
A Very Hot July
July 2021 was the planet's hottest month ever recorded. Official global temperature records date back 142 years to 1880. The last time the world was definitely warmer than today was some 125,000 years ago, based on paleoclimatic data from tree rings, ice cores, sediments and other ways of examining Earth's climate history.
The combined land and ocean-surface temperature was 1.67 degrees Fahrenheit above the 20th-century average of 60.4 degrees F, according to the National Oceanic and Atmospheric Administration (NOAA).
July 2021 also marked the 45th consecutive July and the 439th consecutive month with temperatures, at least nominally, above the 20th-century average, NOAA said.
Due to human-caused climate change, Earth's average temperature has risen more than 2 degrees Fahrenheit (1.2 degrees Celsius) since the late 19th century. It may not sound like much, but it has enormous consequences.
IPCC (Intergovernmental Panel on Climate Change) Report
The Intergovernmental Panel on Climate Change just released Climate Change 2021: the Physical Science Basis, which includes a full report supported by 4000 pages of technical details. Much easier to read is the 42-page “Summary for Policy Makers” at: https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf
The conclusions are dramatic and more than sobering. Among many other things it says, “Human influence has warmed the climate at a rate that is unprecedented in at least the last 2000 years. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.”
But read it for yourself, and note that the IPCC was formed in 1988 by the United Nations, and 195 member governments participate, including the US and Canada. The IPCC is now on its sixth “assessment cycle,” which includes all the reports released from 2015-2021. This report on the physical science will be followed by two more, on impacts/adaptation, and then on mitigation. For the physical science report, 234 scientists from 66 countries volunteered their time to read, compile and summarize all the relevant scientific literature. There are 14,000 references and 78,007 expert and government review comments incorporated. All 195 member governments had to sign off on the report. That deserves repeating – all 195 governments had to agree. When have you ever heard of 195 governments agreeing on anything? Thus, as far as a global consensus goes on any topic, this is as good as it gets.
Thought for the Week
“The clock starts ticking for every living thing in the North on the last days of summer – the dance of hornets and hummers gorging at the feeders, the last gulps of chlorophyll savored by maple trees showing off a red leaf here and there contemplating their autumnal wardrobe, the frogs putting in one last word or two on subjects they have debated back and forth across the marsh since early spring, the birds laying out their tiny suitcases for destinations far and sunny locations wide, and we humans scurrying about in boats with motors and boats with paddles and on beaches of sand and on decks without bugs and on docks with ripening tomatoes. There’s a renewed rush to everyone’s purpose as the sun goes down earlier and starts to rise later and the shadows get cooler and the nights get longer and the days of mid-summer daydreams starts the long fade into our hazy memories.” – Bob Kovar, Manitowish Waters
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