ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

Weights of typical trees on these treatments are multiplied by the appropriate
values in this tabluation to produce the biomass estimates per hectare shown in
table 1.
Tab1 e 1 .--Biomass in 1977 of planted and seeded lodgepole pine
PI anted
Above ground 48.3 61.2 26.9 11.2
Roots 7.3 8.8 4.4 2.1
Total 55.6 70.0 31.3 13.3
Seeded
Above ground 2.7 11.4 4.0 0.5
Roots 0.7 2.0 0.6 0.1
Total 3.1 13.4 4.6 0.6
Nutrient and ash concentrations in the planted lodgepole pine are shown in
table 2. Except for iron, the concentrations did not statistically differ with
respect to treatment. Far less iron was found in the new needles from the chipped-
removed and chipped-returned sites than from the broadcast burned and piled-burned
treatment areas. A similar, but less marked, relationship held true for the iron
contents of the other above-ground tree components. In contrast, the opposi te
occurred in the roots; the iron content of roots on the near-complete (chipped)
units was more than twice that found on the conventionally harvested units.
Only four samples, of five trees each, make up each of the observations in
table 2. As a result, the slightest variation within treatments masks any differ-
ences among them. The data indicate no marked nutrient deficiencies, supporting
field observations of healthy stock on all but the chipped-returned treatment.
Mu1 tiplying nutrient concentrations by the weights of typical trees on these
treatments produced results that show marked differences among treatments in the
amount of some nutrients taken up by the developing tree biomass (table 3). But,
this directly reflects the size and vigor of these trees, not their nutritional
we1 1-being. Gram for gram they all may be equally well nourished.
ORGANIC SURFACE
Soils
The nutrient content of the surface organic layer (Ao), including that of all
chips and debris less than 3 cm in diameter, is shown in table 4. Over the 5-year
post- treatment timespan, nitrogen and cal ci um contents generally increased, and
potassium and magnesium contents decreased. Even though chips had lower concentra-
tions of most elements than the usual forest 1 i tter, the large volume of chips on
the chipped-returned site, in addition to the residual 1 i t ter underneath, resulted
in a larger quantity of every nutrient on this treatment than on any other. After 5
years, total nitrogen was least under burned piles, largely because it was
volatilized when the organic material on the soil surface was burned. Phosphorus
content of the forest litter seems to have been unaffected by treatment. The