ht. Occasional vigorous
young trees just under present merchantable size are of doubtful
value because they are likely to blow down. The most promising
class of undergrowth found in fir forests of the Northwest is where
there has been sufficient light to produce a fairly thick stand
of young hemlock or cedar from five to fifty feet high.

If the undergrowth from which any second crop may develop is
insufficient to be worth much consideration, and reseeding must
be depended upon entirely, there may still be a question as to
species. If ample natural supply of fir seed can be expected, slash
burning is indicated. But if not and the owner is not prepared to
undertake the expense of artificial seeding, while at the same
time there is a promising natural hemlock supply, burning has no
object except the reduction of future fire risk. It may even retard
hemlock reproduction, both by destroying part of the seed supply
and by encouraging the growth of brakes on the area. The question
here is a really financial one. The cost of planting fir under these
conditions may be more than reimbursed by the resultant more valuable
and rapid growing crop. The owner must do his own conjecturing as
to future comparative values of the species.

So far we have discussed slash burning only in its sylvicultural
relation, finding that it encourages Douglas fir reproduction and
is consequently advisable in Northwestern Douglas fir types unless
there is an exceptionally promising second growth already started.
The balance will be further in its favor, in doubtful cases, because
of the protective feature. This is discussed more fully in another
chapter, but it is well to recall here that immunity from recurring
fire is the first essential of profitable reforestation. To secure
second growth by treatment which threatens its destruction later
is bad management unless the original saving is ample to cover
subsequent greater cost of protection. This is seldom the case.

_How to Reseed the Area._

Dismissing the exceptions noted, and returning to our rule that
another crop of Douglas fir is usually the best secured by following
nature--cutting practically clean, burning the ground and starting
a new even-aged stand--we have still to consider means of getting
this stand started. We may depend upon natural reseeding from trees
preserved for the purpose or from the surrounding forest, or we
may resort to planting. What are the comparative advantages of