Eschner, A. R. 1965. Forest protection and streamflow from an Adirondack watershed.
Ph.D. Dissertation, State University of New York, College of Environmental
Science and Forestry, Syracuse, 209 pp.
Summary:
Water and the need for a regular, assured streamflow was one of the main
reasons cited for the passage of laws establishing the Adirondack Park and
authorizing the retention and purchase of land for the Preserve in the late
1800’s. Today, water and its many potential uses is a focal point for
much of the conflict on the status of the Forest Preserve lands. This
thesis provides information which will make possible intelligent evaluation
of the effects of the Preserve on its streams.
On the Sacandaga River watershed a slow one-directional change in land use
and increase in forest cover has been correlated with a decrease in annual,
dormant season, and April runoff over the 39 year period from 1912 to 1950.
In 1912, the total forest stand density and the density of conifers was
near the lowest it has been, after logging, insect attacks and a series of
fires.
As the forest density and crown cover of conifers increased up to 1950,
the streamflow decreased. Also, the average length of time it took
for the most concentrated one-half of the annual streamflow to run off increased
by 19 days, from 67 days to almost three months.
The storm of November, 1950 disrupted the patterns of stand development
and streamflow change. Continuing mortality of trees weakened or exposed
by the storm damage has not permitted the reestablishment of any well-defined
pattern in either stand development or streamflow since that time, although
the changes in quantity and timing of flow reflect the changes in vegetation
and verify in a large measure, the relationship inferred for the previous
period.
It is reasonable to assume that other areas of the Forest Preserve have
had similar changes in vegetation over the period represented by the Sacandaga
record. However, streamflow changes such as those described on the Sacandaga
River watershed above Hope may not be demonstrable for a number of reasons.
There are 20 gaging stations which have been measuring the streamflow from
Adirondack watersheds for more than 40 years, however, the records of 18 of
them mention some upstream regulations in the form of diversion of flow, dams,
or reservoirs, almost all of which appear to exercise a more significant degree
of control than that on the Sacandaga above Hope.
Most of the other streamgaging stations in the Adirondacks measure the flow
from watersheds which have a larger proportion of private land, where logging
has been continuing. Until the 1930’s most of this logging would have
been for conifers and would have helped to keep this most effective component
of the forest stands (in intercepting snow, shading the snowpack, and thus
influencing streamflow) at its early twentieth-century low level.
Although there may be other justifications for its continuance, the policy
of maintaining the Adirondack Forest Preserve as “wild forest lands” does
not serve, particularly well, the watershed management purpose which contributed
to its establishment. A diversity of cover giving the favorable snowmelt
pattern which developed over the 39 year period up to 1950 might have been
accomplished in a shorter time by cutting to create openings and favor conifers.
A managed forest of sound, vigorous trees would be less subject to damage
by such natural catastrophes as insect attack, disease, and high winds with
their adverse effects on Adirondack streamflow.