Wood
defects:
 Some
adjustment to predicted yield may be required to account for yield losses
to log defects like these woodpecker
holes in a live redcedar tree. TIPSY assumes that all trees are
solid wood without these kinds of defects. Top
Poor
stem form:
  Some
adjustment to predicted yield may be required to account for yield losses
due to stem defects like a) this forked
top on a western larch tree (left) and b) this crook
on a lodgepole pine (right). TIPSY assumes that all tree stems have
a smooth continuous bole with a single, live top. Top
Root
rot pockets:
 Some
adjustment to predicted yield may be required to account for yield losses
to diseases like this root rot pocket
in a second-growth Douglas-fir stand. TIPSY assumes that stands
are relatively—but not completely—disease free. Top
Ponds
and swamps:
 If
you conducted a ground-based survey of this stand and wanted a TIPSY
yield prediction for it, you would probably type out this small pond.
Thus, you would not need to apply OAF to the predicted yield to account for the
pond area. However, if you were working off of the typical forest cover
inventory file, this pond would not be identified. Thus, you would need
to apply an OAF to the predicted yield to account for the pond area. So, depending
on the resolution of your data, some adjustment to predicted yield may
be required to account for yield losses due to small water bodies, like
this beaver pond in a young lodgepole
pine stand. TIPSY assumes that, whatever the density, there are no
large holes in the stand. Top
Low
density:
  No
adjustment to predicted yield is required to account for wide spacing—like the very wide spacing in this young lodgepole pine stand. (Left
photo, right photo) TIPSY can
predict yield across a wide range of post-spacing densities and will
predict reduced yield for wide spacing. As long as there are no large
holes in the stand, no further adjustment to predicted yield is necessary
to account for the wide spacing, though adjustments may still be required
for the other factors illustrated on this web page.
Top
Disease:
  Some
adjustment to predicted yield may be required to account for yield losses
to disease like a) this gall
on an older lodgepole pine, (left) and b) this lodgepole
pine that has lost foliage to lophodermella (right). TIPSY assumes
that the stand is relatively—but not completely—disease free.
Top
Non-commercial
cover:
  Some
adjustment to predicted yield may be required to account for yield losses
to small pockets of non-commercial cover like a) this
patch of aspen within a young lodgepole pine plantation (left) and
b) this alder pocket within a spruce-balsam
stand (right). TIPSY assumes that there are no large pockets of
non-commercial cover. Top
EP922.02:
 Some
adjustment to predicted yield may be required because TIPSY is calibrated
to predict “potential yield”—the yield expected from uniformly
stocked, healthy stands. This photo of EP922.02
illustrates several common features of the data used to calibrate TIPSY.
Note the high degree of uniformity of site and stocking and the low
incidence of forest health damage. Top
Non-productive
area:
 Some
adjustment to predicted yield may be required to account for yield losses
to small patches of non-productive land like this slide
in the middle of a Douglas-fir plantation. The resolution of your
data determines whether you must apply an OAF to predicted yield. If you conducted
intensive ground sampling of this polygon and typed out the slide area,
you would not need to apply an OAF to predicted yield to account for the non-productive
area. However, if your input data was the typical forest cover inventory
information, the slide area was too small to show up, and you wanted
to apply the predicted yield to the entire polygon, you would need
to account for the non-productive slide area by applying an OAF to the predicted
yield. Top
Rock
outcrops:
 Some
adjustment to predicted yield may be required to account for yield losses
to small rock outcrops scattered throughout a polygon, like these small
rock outcrops in a lodgepole pine plantation. TIPSY assumes that,
whatever the density, there are no large gaps in the stand.
Top
Old
roads:
 Some
adjustment to predicted yield may be required to account for yield losses
due to old roads and skid trails, like this old
road in the middle of the plantation. The way in which you structure
your analysis and prepare your data determines whether you must apply an OAF to
predicted yield to account for the old roads. For example, if you make
some overall reduction for productive land lost to roads, you will
not need to apply an OAF to predicted yield to account for them. Also see the discussion
for Ponds and Swamps and Non-Productive
Area. Top
Senescence,
stand break-up, and succession:
 Some
adjustment to predicted yield may be required to account for yield losses
at very old ages in stands that are breaking up,
like this old lodgepole pine stand where the overstorey pines are
losing vigour and dying out, and spruces and balsams are growing into
the canopy. TIPSY assumes that live trees have live, single stem tops,
and does not have the capacity to simulate stand break-up and succession. Top
Espacement:
 Some
adjustment to predicted yield may be required to account for a difference
between the actual inter-tree spacing in a stand and the inter-tree
spacing assumed by the TIPSY simulation for that stand. Variation
in the spacing between trees is evident in this Douglas-fir plantation.
Each TIPSY run assumes a particular pattern of distances between trees.
Top
Slash:
 Some
adjustment to predicted yield may be required to account for yield losses
if excessive slash loading prohibits seedling establishment, like this
landing slash in a recently harvested
coastal Douglas-fir stand. TIPSY assumes that to whatever density
the stand is regenerated, there are no large piles of slash that
prohibit seedling establishment. Top
Animal
damage:
  Some
adjustment to predicted yield may be required to account for growth
reductions, log defects, and mortality due to animal damage, like a)
the damage on this young lodgepole pine
tree and b) the elk damage to this Douglas-fir. TIPSY assumes
that trees in the stand grow with only low levels of animal damage.
Top
Waste:
 Some
adjustment to predicted yield may be required to account for logging
waste if you want TIPSY’s merchantable volume predictions to
indicate the volume that will be removed from the site. Use of the appropriate
merchantability limits in TIPSY will help, but depending on the characteristics
of the trees left as waste, some additional adjustment may be required.
TIPSY’s merchantable volume/ha prediction includes the stem volume
between stump height and minimum top diameter of all live trees above
the minimum diameter. Top |
