Discussion
With anticipation
of sampling from 36 sites, six (6) sites per strata, initial results of
the stand selection criteria are quite poor. Sites in the Southwest/Low
strata were limited to only eight stands prior to applying the
selection criteria, limiting the stand population from which to select
from. However, this does nto explain the low overall number of stands
per strata.
In light of this
information, two reasons may explain the poor
results. First, the GIS data may not accurately represent the true
forest characterstics. The Darkwoods property changed hands between
logging firms several times over the past century. This
allows for the potential of data loss or mis-translation between
different managers, as each company likely had different methods of
tracking and managing stand information.
Second, the GIS
information
may be correct, but the stand selection criteria may simply be too
strict. A forest exhibiting characteristics exactly as I searched
for are likely very rare in the real world, so I should not expect to
find more than a few suitable stands, as was the case. However,
determining the most limiting criteria may be important in
understanding the nature of the forests in the Darkwoods.
To address this, I performed a search of stands using modified selection criteria as follows:
1. NE or SW aspect dominated stands;
2. Within NDT 2-4 classification boundaries;
3.
Presence
of at least two separate cohorts with the following
characteristics:
3a.
Primary species <=
60% of stand composition AND is either ponderosa pine (Pinus ponderosa), Rocky Mountain
Douglas-fir (Pseudotsuga
menziesii
var. glauca), western larch (Larix occidentalis) or lodgepole
pine (Pinus
contorta),
OR
3b.
Secondary species >= 35% of stand composition AND is either
ponderosa pine (Pinus ponderosa), Rocky Mountain
Douglas-fir (Pseudotsuga
menziesii
var. glauca) or western
larch (Larix
occidentalis).
4. Stand is not designated with EPA status.
Note: These are the same criteria as before, but do not include the anthropogenic influence criteria.
After processing these criteria, a dramatic increase in the number of selected stands was apparent (Figure 8). Of the resulting 448 stands, the "Northeast" aspect class had 56 stands within the "High" elevation class, 119 within the "Mid" and 94 within the "Low." In the "Southwest" aspect class, 63 were in the "High" elevation class, 111 in the "Mid" and five (5) in the "Low" (Table 7).
These results indicate stand age and logging as a major limiting factors in the preliminary stand selection process. Given a minimum number of 3 sites per strata as necessary to perform statistical analysis between sample sites, these results would prove useful for further analysis. However, stand age and logging are major indicators of historic anthropogenic influence in forest structures, and are, therefore, factors I cannot overlook.
