Monday, October 19, 2020

A Northwoods Almanac for 10/16/20

 A Northwoods Almanac for 10/16-29, 2020  

 

Sightings: Tamarack Gold, Loons, Pine Siskins, Lapland Longspurs

Tamaracks are in full golden splendor. As the only conifer in the North Country to drop its needles in the fall, the spectacle has a short shelf life, so enjoy it while you can. In the winter, many a person has misinterpreted the naked branches of the tamarack to mean the tree has died, but as Donald Culross Peatite wrote in his 1948 book A Natural History of Trees, “When spring comes to the North Woods, with that apologetic rush and will to please which well become the tardy, these same trees . . . begin, soon after the wild gees have gone over and the ice in the beaver ponds is melted, to put forth an unexpected, subtle bloom.  . . . There is no more delicate charm in the North Woods than the moment when the soft, pale-green needles first begin to clothe the military sternness of the Larch. So fine is that foliage, and so oddly clustered in sparse tufts, that tamarack has the distinction among our trees of giving the least shade.”


photo by John Bates


On 10/8, Mary and I watched an adult loon feeding a chick. This is exceptionally late  for an adult to still be feeding a chick given that the adults are soon to migrate, followed a few weeks later by the chick. Both the adult and the chick, however, were the same size, so perhaps this was a chick simply overly dependent on the adult. One way or another, it needs to learn full independence very quickly or its odds of surviving migration are slim.

A flock of 12 pine siskins appeared at our feeders on 10/7. I’ve seen reports of a hundred or more pine siskins overwhelming people’s feeders in southern and central Wisconsin, so I’m curious to see whether we will experience a similar deluge in the next few weeks.


pine siskin photo by Bev Engstrom


And in a walk on Powell Marsh also on 10/7, we were delighted to see a flock of eight Lapland longspurs who allowed us to approach very closely. Lapland Longspurs breed in tundra habitats across the arctic, their name referring to the Lapland region of Scandinavia. We rarely see these birds in migration, so this was a treat.


contributed photo

 

Wild Lakes

            I mentioned in my last column that I’m working on a new book describing the last and best undeveloped lakes in Northern Wisconsin for paddling. With winter biting at our heels, the book will have to wait until next spring to be completed. Still, Mary and I camped last week for three days on Lake Laura in Forest County, and we paddled seven new wild lakes while walking in to another two. 

It’s fascinating to me how each lake has an immediate personality based on the convolutions (or lack thereof) of its shoreline, its shoreline vegetation both onshore and in its shallows, its sediment composition (muck or sand or cobble or combinations thereof), its put-in (from asphalt boat landing to walking across part of a peat bog), its ease in getting to (can I drive right up to it or portage in on a rough trail), its immediate presentation of wildlife (loons calling, flocks of ducks, etc.), and its very subjective beauty, wildness, and mystery.

We were particularly taken by Savage Lake in Florence County, a 144-acre wild lake that was an adventure to find, and which was only three feet or so in depth for most of our paddle. The shoreline was often comprised of mature eastern hemlocks and white cedars, and the put-in was nothing more than a scrape between two hemlocks. We kicked up numerous flocks of ducks, and the beavers clearly were at work on the aquatic vegetation. It just had that feel of a wild place seldom visited, though there was a parking area and a sign for the lake once we found it.



We never saw another person for the hours we were in the area, and it was a beautiful fall Saturday afternoon.

Entering a wild place, as Paul Gruchow writes, “speaks not to what we have learned from books, but to whatever depends upon experience with the physical world: knowing how to read a footprint in the mud, how to steer a canoe into the wind . . . what sort of weather the clouds and the wind foretell . . . which bird sings overhead, what flower blooms in the marsh.

“It speaks to that which is a gift and not an acquisition . . . Nothing here - not the mists that rise in the morning, nor the wind that blows at midday, nor the curtain of colors that falls in the evening, nor the slap of a beaver’s tail in the night - can be commandeered, or caused to happen, or forbidden.

And it speaks “to our capacity for delight and wonder . . . to the sense of mystery surrounding our lives . . . to the latent feeling of fellowship with all creation.”

Indeed. I often have to remind myself that all I am called to do on these lakes is pay attention and to breathe it all in as deeply as I can. The lakes, like all life, wish only to be honored for who they are, and my deepest hope is that we’re doing just that while we’re there.

 

Leaves! CPOM 

Leaves, leaves, and more leaves; that’s THE story of October. Billions, well, more likely trillions of leaves, have fallen in the last three weeks, producing a dizzying kaleidoscope of colors on the ground and an incessant noise as one scuffles through the dry leaf litter. 

What happens to them all? Why aren’t we awash in a sea of leaves arching over our heads? There are two stories here: one involves the leaves landing on the forest floor, and the other involves leaves that fall onto our lakes and rivers.

 Let’s just consider the leaves now floating on our northern waters. Mary and I have spent much of the last month paddling undeveloped lakes, and on every lake, recently fallen leaves drifted colorfully, whether from overhanging shoreline trees or from wetland shrubs and herbaceous plants clothing the shores and extending out into the shallows.

By next spring, these leaves will be gone, but gone where? Most of us don’t consider the leaves as food for aquatic life, but indeed that’s exactly what they are. Since the forests along the headwater streambanks shade the river, limited photosynthesis typically takes place. In fact, as little as 1 percent of the stream's energy may derive from photosynthesis. Thus, in the headwater streams of the Northern Highlands where we live, the forest vegetation along a stream is the main energy source for life, typically providing most of the energy for organisms living in and along the stream. Leaves, needles, twigs, bark, and branches drop or wash into a stream and become a storehouse of organic material needed by stream organisms. 

This shower of organic materials from the forest provides a rich food base for a diverse population of insects and microbes that browse and shred the leaves, gouge tunnels into logs and branches, and rasp off algae and fungi. Nearly two-thirds of this debris is processed within the headwaters, with very little of it leaving the headwater system without being at least partially processed. 

This rain of leaves and twigs is termed “coarse particulate organic matter” (CPOM), and  streams are dominated by insects in particular that shred the leaves, but only after they’ve been colonized and conditioned by microbes that leach out soluble organics. Typically one-third or more of the dry weight of a leaf is lost through leaching in the first two days. The continued conditioning done by microbes like protozoans, bacteria, and aquatic fungi may yet take weeks or months depending on the plant species and on the stream temperature. Leaves from basswood, alder, and most herbaceous species process quickly. Maple and birch leaves process somewhat more slowly, while oaks, conifers, and most ferns break down very slowly. 

If the headwaters are turbulent, the mechanical action of the water abrades the leaves and helps tear them apart.

The shredder insects, like many stoneflies, eventually get into the act, skeletonizing the leaves, and converting about 40 percent of what they eat into their own tissue and respiration. The microbial organisms that helped condition the leaves for the shredders are also ingested, serving I suppose as the protein in the leaf sandwich.

So, shredders set the table for the collectors downstream, as well as for another group of insects called grazers or scrapers. Collectors filter their food from the water, or gather what they need from the sediments, while scrapers shear attached algae and other materials from rock and plant surfaces in the water. The shredders turn the CPOM into FPOM (fine particulate organic matter), acting like food grinders to make the materials smaller and more digestible downstream.

In smaller streams like the size of the Manitowish River, shredders and collectors are co-dominant. In mid-sized rivers, collectors and scrapers are co-dominant. In big rivers like the Mississippi where significant photosynthesis takes place, collectors are dominant.     As the particle size of leaves and other organic matter becomes progressively smaller downriver, the stream community becomes progressively more efficient at processing the smaller particles that arrive at its table.




In the meantime, predatorial insects like dragonfly larvae,  various fish, and a host of others, feed constantly throughout the stream orders. 

The takeaway? Streams (and lakes) are highly dependent on the forest systems around them. It’s a holistic system that begins with leaf fall in autumn. 

 

Celestial Events

            The new moon occurs tonight, 10/16. 

The peak Orionid meteor shower occurs before dawn on 10/21 - look for 20 per hour. 

On 10/22, look after dusk for Jupiter two degrees above the waxing crescent moon and Saturn just above it at three degrees above the moon.

The average low temperature in our area drops below freezing as of 10/22, this for the first time since April 22. Minocqua averages 183 days with low temperatures at or below freezing. That’s exactly half of the year.

 

Thought for the Week

“This is the true joy in life, the being used for a purpose recognized by yourself as a mighty one; the being thoroughly worn out before you are thrown on the scrap heap; the being a force of Nature instead of a feverish selfish little clod of ailments and grievances complaining that the world will not devote itself to making you happy.

“I am of the opinion that my life belongs to the community, and as long as I live, it is my privilege to do for it whatever I can. I want to be thoroughly used up when I die, for the harder I work, the more I live. Life is no ‘brief candle’ to me. It is a sort of splendid torch which I have got hold of for a moment, and I want to make it burn as brightly as possible before handing it on to the future generations.” - George Bernard Shaw

 

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