Letters to the Editors: Autumn 2008
Porcupines, Chickadees, and Evolution
To the Editors:
As always, I enjoyed Bernd Heinrich’s informative and engaging piece on porcupines. At one point, referring to porkies’ habit of savaging tree branches for only a few nibbles, he wonders at what seems “terribly wasteful” behavior in light of his notion that animals are – or should be – more efficient in their foraging behavior.
As I was wondering the same thing, I thought of the chickadees and nuthatches at my feeder, who often toss out two or three perfectly good seeds before flitting off with one. The ground is covered with their “waste,” which is, of course, being gobbled up by hosts of sparrows, towhees, and other ground-feeders. Clearly the chickadees are not doing this “for” their friends below, and yet undeniably, this behavior causes many more critters to flock around them. If I were a chickadee, I would feel a lot safer surrounded by other like-minded critters than if I were alone. Should a hawk or a cat appear, their flight will warn me of the danger. My guess is that “feeding” others in this fashion is adaptive for chickadees.
How might this inform our thinking about the porcupines? That is, if we think of any given behavior as dictated solely by the individual’s inclinations (as we North American humans are wont to believe), then gnawing a treeful of branches to nibble a few needles would be inefficient. But if we think of behavior as shaped in significant measure by the communities around us, if we conceive of the community itself as an adaptive system, then porkies would appear to be good citizens, after all. Perhaps in some sense, those porcupines that have been “wasteful” in this way have benefited from the increased activity that their profligacy has generated.
This is not to say that Heinrich should be sanguine about losing his precious chestnuts or beeches to these sluggish thugs. I know just how he feels. Keen observer and master teacher that he is, I suspect he knows all this anyway. After all, he had the good grace to note that this observation challenges his conception. So my question is: is it useful to imagine that evolution works not just at the individual level or even the species level but at the level of the ecosystem itself?
L. A. Parks Daloz, Clinton, Washington
Bernd Heinrich replies:
The chickadee and nuthatch behavior that is described is indeed analogous to that of the porcupines. And they’re not the only ones that act this way. The blue jays and woodpeckers at our feeder are even more “guilty” of feeding the finches, short-tailed shrews, deer mice, and chipmunks. I use un-culled sunflower seeds in the shell, and at the feeder where there is a lot of choice, the birds try to find the best seeds of the lot. In a study we did a few years ago, we found that chickadees and red-breasted nuthatches pick up and throw away perfectly good-looking shells when those shells are empty. They take the full ones and fly off with them, then perch on a branch and hammer them open to get the meat inside. We learned also that they can be tricked into hauling off perfectly bad shells, provided they are filled with plaster-of-Paris and therefore weigh more than the empty duds. In short, the birds heft, and then either heave or leave.
Secondly, the birds scrape through the seeds to find the few that they don’t need to shell at all, discarding many of those with shells (that require work to open). Are we different? When we pick apples out of a pile at the grocery, we may not squeeze or taste every one to try to find the plumpest and sweetest, but we do the next best, still socially acceptable thing: we choose those without a bruise. The rest, whether we realize it or not, we donate to the mice, fruit flies, and bacteria.
Yes, the porkies are indeed “good citizens” to the rabbits and deer in the same way that we are generous donors to the mice and the flies. It is possible that such good citizenship is not just incidental and that it evolves, which, as the reader realizes, is what a major thread of evolution is all about. Think of the co-evolution of bees and flowers, berries and birds, predators and prey. But there needs to be feedback. Until proven otherwise, I doubt that the porkies’ behavior is shaped by deer and rabbits eating cast-off hemlock twigs, just because they are the porkies’.
Nor are we likely to be rewarded by the mice for leaving them bruised apples. In short, such helping behavior can’t be selected for. If it were indeed otherwise, then we’d first of all have to prove that a porcupine earns a reproductive advantage, by feeding a deer or a rabbit, over another individual who does not. If so, that might raise the possibility that such “helping” behavior could potentially have evolved. But, that’s still a long way from knowing if there is indeed an evolved partnership.
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Rusting in the North Maine Woods
To the Editors:
As luck would have it, I was reading Rust in Peace (Summer 2008) while sitting on the porch of the Historic Pittston Farm, deep in the heart of the North Maine Woods. The next day while kayaking down the South Branch of the Penobscot River to Seboomook Lake, you could see fence wire “rusting in peace” in the trees along the river bank. The spruce grove of today at one time must have been a hayfield or pasture for the farm’s animals. The Historic Pittston Farm, now an inn, is the last remaining of the four farms that were once owned and operated by the Great Northern Paper Company of Millinocket. On any given day, upwards of 75 or more lumberjacks and river drivers plus cooks and other staff would call the farm home. Also during the winter months, 75 or so horses would be at the farm to help in yarding the logs out of the woods. A trip to the farm provides a great look back at the bygone area of logging in the North Maine Woods. It has been fixed up by the new owners, and the meals are out of this world. Truly a unique outpost deep in the heart of the Pine Tree State.
Steve Yenco, Lisbon Falls, Maine
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A Need for Mentors
To the Editors:
Bob Perschel’s article on timber marking moved me to write. I would only pray and fervently hope that others might serve as equal mentors to younger foresters.
R. C. Greenman, Delmar, New York
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Overcoming the Slump
To the Editors:
I am writing in response to Stephen Long’s Summer 2008 The Long View concerning the recent downturn of the forest products economy. I think good sustainable forestry goes beyond what happens in the woods. Although leaving an intact forest is of grave concern, the social and ecological impacts of current logging methods and the markets supplied ought to be carefully scrutinized. How much damage is wrought by the manufacture, acquisition, and fuel consumption of machinery and transportation of wood? Is this wood used wisely?
The fact that a simple economic downturn and rise in the cost of diesel have heavily impacted the industry is an obvious sign of its inherent unsustainability. Rather than bemoaning the hard times and hoping things return to normal, we should make use of this opportunity to transition to a more sustainable model.
Current logging practices tend to emphasis time efficiency while ignoring resource efficiency. Mechanization saves labor but requires a larger input of resources, mainly fuel. We all know about the ecological (global climate change) and the social (war) impact of insatiable demand for oil. A trend away from mechanization would provide a myriad of benefits: logging would take far more time and thereby create more steady labor for more people. There would be less dependence on oil. Lower overhead and smaller loans for equipment would result in a greater proportion of money going to wages instead of manufacturers, insurance companies, and banks, which would mean less pressure for loggers to maintain high production, resulting in a safer workplace and a more conscientious job.
If there are two million unsold homes, are we making good use of all the wood? I think the global market is based upon the senseless transport of materials to create products of dubious usefulness. I’d rather see veneer maple used as firewood than in a door or cabinet in an unoccupied, 3,000-square-foot house far away.
The Northern Forest can help supply its inhabitants with our main need for fuel, as well as the materials to maintain, repair, or replace buildings, implements, and other necessities. Local processing and sale would strengthen our economy and create jobs, save enormous quantities of fuel used for transport, and significantly reduce the threat of moving invasive species around.
Sustainability builds upon itself. Minimal use of technology and resources leads to less need for income. The resulting low cost and good quality of products creates local demand.
Anders Krauss, Sheffield, Vermont
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Overcoming the Slump
To the Editors:
The housing market is down. The American timber industry is in a huge slump. Big mills are closing, loggers are going out of business, and thousands of jobs have been lost, with little hope for the future. Both our timber and our jobs continue to be exported to the Far East. Globalization has changed our local timber market, and forest owners and the forest are hurting, too. After reading Stephen Long’s The Long View in the Summer 2008 issue, I had to contact you to share what we do.
Our family’s forest-to-finished-flooring business gives us the advantage in the market today by selling our annual timber harvest directly to our customers as high-value, manufactured products.
We developed this business 20 years ago on our 200-acre woodlot to generate enough money to spend the time to do excellent forestry and logging.
We grow 400 board feet of high-quality hardwood per acre annually, a high rate for our region. We currently need to cut only a small portion of our growth to supply our business. We harvest up to one tree per acre each year, using “arthroscopic logging” with the smallest possible equipment, always taking the worst tree first. Flooring sells for $10 per square foot in the city – our income potential is amazing. This business could support one good job for every 40 acres of timber.
A WoodMizer sawmill and solar-heated lumber kilns are used to produce boards that we manufacture into flooring and other high-value products in our remodeled dairy barn. We install our mixed-species, character-grade, custom-blended flooring in our customers’ homes, earning us full retail value for our trees.
By keeping the business simple and complete – we eliminate every middleman, broker, and shipper – we keep all the value right here. We earn 1,000 times the market value for small-diameter trees, 100 times the stumpage value of our low-value sawlogs, and 10 times the value of our best standing trees. Finished wood products are very valuable.
We have created a new timber market where the forest owner is in full control and earns a good profit for his effort and investment. A fantastic forest and a wonderful way of life is the end result. I encourage all forest owners to learn about this alternative to the traditional timber markets. www.TimberGrowers.com has information on our business.
Jim Birkemeier, Spring Green, Wisconsin
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