248 ANDERSON 



equipment and no more botanical training than you now have. We'll take 

 this tree as the center of a hundred-foot circle. What has happened here in 

 a century? Don't neglect any kind of evidence, just because it seems trivial. 

 The world is full of easy keys to important problems; only once in a while 

 does a genius come along and label these trivial keys as significant evidence. 

 I warn you there is such a key here, and most of you will ignore it — though 

 it is in plain sight and requires no book learning to interpret correctly. Any 

 one of you could solve this problem given a day or two; several of you I 

 know will work it out laboriously this afternoon; is there anybody here who 

 can find the easy way in the first five minutes?" 



There wasn't. In twenty years I have had just two students who had the 

 wit to notice that all the time I was talking to them my left hand was play- 

 ing idly with a scrap of barbed wire which sticks out an inch or so from a 

 scar on the big oak. Off to the left about thirty feet is another tree with a 

 similar scar, though without any barbed wire, and way off to the right in more 

 or less of the same straight line is another oak with two such horizontal scars, 

 one about a foot above the other. There had, you see, been a wire fence strung 

 through the woods, using the trees as posts. When the land on both sides of 

 it was acquired for an arboretum, the barbed wire was mostly removed, but 

 it had stayed in place so long that some of the trees had buried it in their 

 bark. This was more than just a fence row; it was a section line, the bound- 

 ary between two farms which had been differently managed. One had been 

 cut over and fairly heavily grazed ; the other family had only taken out a tree 

 here and there. If one figures out where the fence once ran and then comes 

 and stands on the fence line and faces first toward one farm and then turns 

 round about and faces away from it, he sees two different landscapes. On one 

 side there are few large trees, no big oak, and a good number of vigorous 

 young trees in groups of two or three, showing where an old stump had 

 sprouted. There are plants which indicate a former pasture, a few surviving 

 grasses, and one prairie rose not too happy in the shaded woodland. There 

 are a number of dead red cedars, red cedars being planted everywhere there- 

 abouts by the birds but able to survive only in the sunlight. In the other 

 direction there are big oaks, little underbrush, no stump sprouts, no cedars, 

 and scattered dogwoods. Facing west, one looks into a tjqjical first-growth 

 white-oak-sugar-maple woodland; facing east into vigorous second-growth 

 woods. If he looks up and down the old fence line he can see how, for some 

 decades, the woodland trees sent husky branches out sidewise toward the 

 sunlight of a brushy pasture, branches which are just now beginning to die 

 in the heavier shade of the maturing second growth. 



The greatest delight I ever had as a teacher was when at last one alert 

 student glanced at the barbed wire I had been handling, looked back and 

 forth along the line of old trees for further scars, stood on the former fence 

 line looking first due east and then straight west, then gave me a wink and 



