LOGGING PRACTICE IN THE LAKE STATES 43 
know specifically what measures are the most effective to bring 
about those conditions in the handling of this or that kind of forest. 
An attempt is therefore made to discuss here such specific measures 
and their effectiveness. This discussion will, for each type of forest, 
include both the first essentials for keeping forest land productive 
and, in addition, the more intensive measures without which the full 
productivity of the land can not be realized. Such measures, how- 
ever, as the necessary protective organization, which is alike for all 
forest types and can be adequately considered only for the region 
as a whole, will not be treated here. 
HARDWOOD-HEMLOCK FORESTS 
CUTTING ONLY TREES OF SAW-LOG SIZE 
The present practice, not uncommon where there is a market for 
chemical wood, mine timber, and ties, of cutting trees below saw-log 
size into these products, is very destructive to the future of the forest 
land. Even if the logged-off land is protected from fire, much of the 
young reproduction already on the ground dies when suddenly ex- 
posed to light, especially such species as hemlock, beech, and even 
some maple. ~ What is left of the reproduction, together with the 
sprouts from the stumps, may eventually make a fairly dense stand 
of timber, but it will take at least from 100 to 120 years before any 
saw-log timber can be produced again, and this is likely to be of 
low grade and of the less desirable species. If there is a market for 
mine timber, ties, and chemical wood, they should be obtained, as far 
as possible, from the tops and larger limbs of the felled trees or from 
second-growth stands in need of thinning. - 
In hardwoods it is not economical to cut trees below 13 or 14 
inches in diameter, because of the high cost of logging and the low 
grades of lumber obtainable from them. The most economical diam- 
eter limit will vary, however, with each individual operation, with 
the species, and with the market conditions, and should be deter- 
mined separately for each tract. 
The measures essential for keeping hardwood land productive are 
thus comparatively simple. They involve no essential change in the 
present logging practice, except that the trees belowsaw-log size should 
not be cut and that care should be taken in logging to cause as little 
damage as practicable to the remaining trees. In the birch—beech— 
maple forest. this would mean leaving trees below 12 or 18 inches in 
diameter, breast high. Where hemlock is present in the stand it 
should be cut to as low a size as is marketable for pulpwood, since, 
if left standing, hemlock is likely to be windthrown or, with the 
opening up of the forest, to die as the result of exposure to light. 
A typical northern hardwood forest is invariably made up of trees 
of different sizes and ages, from large trees 36 inches and over in 
diameter to a carpet of seedlings 1 year old, particularly of hard 
maple. An actual tally of 77 acres of birch—beech—maple forest 
showed the distribution of trees of different sizes on an average 
acre as indicated in Table 8. 
