Vol. 16—1962 - NorthEastern Weed Science Society

Another pote1U:ialuse for chemicals in forest management has to do with the thinning'
of plantations that are compoBedot species that are liable to infection by~
annosus f Tbisrooc rotting organiBm'epreads both subtei'raneally and by spores and
is particularly serlousin plantatiou& tIU\t are in the pale stage. Thinning by the conventional
method of cutting creates stUmps that are infection sites for the activated
spread of the pathogen but it is possible to circumvent thi8:difficulty if the trees to be
thinned arc poisoned by frilling and allowed to disintegrate in place. Since so many of
the earlier tbinnings in plantations do not yield usable wood, it is entirely possible that
this means of thinning will not only cost less but be productive of fewer hazards.
There are many woodland owners today who are interested in growing Christmas
trees. Where there is available open land, there are few problems that a good mowing
cannot cure. The situation is somewhat different with those who plan to raise their
trees in areas that are already wooded. It is possible for them to clear off a patch of
woods and to maintain this area in an open condition at the expense of much time and
labor. A more feasible method involves the thinning of the present forest cover to
permit enough light on the forest floor to encourage the growth of coniferous transplants.
We have tried this and it seems to work. We thinned an oak-maple-hickory stand
rather heavily and after sprouting had taken place, treated the cut stumps with a
2, 4, 5 - T solution in kerosene. Some months later we planted the area to 2 x 0
Norway spruce, and after one growing season they appear to be doing well. The competition
from what hardwood sprouts remain is inconsequential.
The release of conifers from hardwood competition has always seemed to be a
most logical occasion on which to use chemicals. In view of what I have said previously,
I hope you will forgive if I do not wholly subscribe to this seemingly obvious contention.
I am ready to admit, however, that there are some sites where the relative productive
potential of the site under conifers is so superior to anything that we can hope to derive
from hardwoods grown on the same site, that little doubt exists as to the advisability
of chemical release work. I am immediately reminded of some of the problems that
our cohorts to the south are faced with. But there are large areas of the Northeast
where conifer release is not justified economically or sUviculturally and, as I have
tried to indicate previously, wemust know more about site quality as it affects growth
and be more certain in our predictions that future markets will offer suitable compensation
for the costs involved.
There are many other subsidiary uses of chemicals in forest management and,
depending on what you do and where you happen to be, they may be of considerable significance
to the success of an operation. I have encountered references to the use of
chemical weed control in watershed management and in fire protection and both, in
their respective local areas, were considered to have great promise. The emphasis,
however, continues to be on the herbicidal control of "undesirable" species, and it is
this type of blanket prescription which prompted me to enter upon this discussion of
change, uncertainty and the insufficiency of our present knowledge about what is or is
not desirable.
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