COTTONWOOD IN THE MISSISSIPPI VALLEY. ao 
tops. Where the size of logging operations does not warrant setting 
up such secondary plants, it will often be possible to barge the logs 
or bolts of the inferior species to hoop mills, excelsior factories, or 
cooperage plants located in the principal cities along the river. Even 
though the price received no more than covers the woods and trans- 
portation cost, the importance of encouraging cottonwood reproduc- 
tion will often justify such a disposal. 
Charcoal burning and wood distillation is another industry which, 
if it could be profitably conducted in these bottoms, would aid 
materially in close utilization. Practically every species could be 
utilized down to a diameter of 2 or 3 inches, including tops and 
limbs of felled trees. Maple, elm, sycamore, willow, birch, and hack- 
berry should produce a good grade of charcoal, and be delivered at 
the pit for $2 per cord. The development of a anarket for small- 
sized material would have the additional advantage of making thin- 
nings from young stands of cottonwood practicable. In many in- 
stances, however, the utilization of the poorer species will obviously 
be out of the question. A choice must then be made between leaving 
them until a market develops or deadening them. 
THINNINGS. 
The removal of a portion of the trees from a stand not fully 
mature is termed a thinning. Thinnings, if properly done at the 
right time, will result in accelerating the growth of the trees left, 
and at the same time utilize many of the smaller trees which would 
otherwise die from supression. A thinning will frequently pay for 
itself. Cottonwood responds in a marked degree to increased light. 
Its pronounced ght requirement is in itself an unmistakable indica- 
tion that thinnings will be beneficial. It is evident, further, that in 
cottonwood stands where in the course of natural development the 
cverage number of trees per acre falls from 700 to 50 between the 
ages of 10 and 40 years there must be great loss in growth rate due 
to competition. 7 
Unfortunately, no example of systematic thinning in young cot- 
tonwood stands was found in the present study. On one plot, how- 
ever, a good many of the trees had been removed in a rather hap- 
hazard and unsystematic manner, most of them apparently of the 
smaller sizes. The beneficial results of this chance opening up 
were, however, quite apparent. This particular stand was in south- 
eastern Arkansas, and occupied good bottomland soil near the 
present course of the river. Its age was 17 years. It was stated that 
rivermen had been in the habit of drawing upon this stand from 
time to time for ship poles, barge braces, and the lke. Cuttings 
were said to have been made for quite a number of years, although 
apparently none had been made very recently. Over most of the 
