102
J . ROGER BRAY A N D EVILLE GORHAM
used as fuel, and leaves as bedding for farm animals or as a soil treatment. In Germany such utilization prompted concern over site degradation, and provided a stimulus for Ebermayer’s (1876) classic work on
the production and chemical composition of forest litter. This study
demonstrated conclusively the importance of litter-fall in the nutrient
cycle of the forest, at the same time that its significance in soil development was being shown by Miiller’s (1887) pioneer investigation of the
types of forest humus layer. More recent studies of the importance of
litter-fall in the forest ecosystem have been reviewed by Lutz and
Chandler (1946).
I n the future, forest litter may assume additional significance. The
current rapid increase in human population, with its consequent
pressure on food supplies and accelerated depletion of non-renewable
resources such as coal and oil, will eventually necessitate much fuller use
of the world’s organic production (cf. Gaffron, 1946). To be thoroughly
efficient such utilization must be mainly a t the level of green plants,
the primary producers in the food web. It will also depend upon cheaper
sources of energy and on great expansion of biochemical engineering,
with current plant residues of all kinds serving as raw materials in
addition to the present mainstays - agricultural crops, tree boles, and
fossil plant deposits of coal and oil. Because much of the world’s land
is best suited to the growth of trees, and wood will in any case remain
a valuable raw material in its own right, forests will probably be a
major source of materials for the new biochemical technology, particularly since mature stands can in certain circumstances be managed
economically on a sustaining basis by selective felling. Moreover, forests
utilize both light and growing season to a much greater degree than
most agricultGa1 crops, especially if the trees arel evergreen. Total
yields of forest dry matter compare favorably with those of farm crops,
even without the constant cultivation and fertilization the latter receive
(Weck, 1955 ; Ovington and Pearsall, 1956; Ovington, 1956).
If forest production is to be used with maximum efficiency, the leaves
and other debris should be utilized along with boles and slash, since they
make up an important part of the total yield (see Table XX, p. 148).
One promising use of leaf litter is as a source of protein which could be
extracted from the leaves and incorporated into palatable foodstuffs.
Such protein is “not as good as milk protein, but is as good as, or even
better than, fish meal” (Pirie, 1962). Pirie (1953, 1958, 1961) has provided cogent arguments for attempting the extraction of protein from
forest and agricultural waste on a commercial scale, and the cultivation
of useful micro-organisms on the residue. The cultivation of edible
fungi on beds of forest litter or on the forest floor itself (“fungal farming”) is another use of litter which might add to the world food supply.
J . ROGER BRAY A N D EVILLE GORHAM
used as fuel, and leaves as bedding for farm animals or as a soil treatment. In Germany such utilization prompted concern over site degradation, and provided a stimulus for Ebermayer’s (1876) classic work on
the production and chemical composition of forest litter. This study
demonstrated conclusively the importance of litter-fall in the nutrient
cycle of the forest, at the same time that its significance in soil development was being shown by Miiller’s (1887) pioneer investigation of the
types of forest humus layer. More recent studies of the importance of
litter-fall in the forest ecosystem have been reviewed by Lutz and
Chandler (1946).
I n the future, forest litter may assume additional significance. The
current rapid increase in human population, with its consequent
pressure on food supplies and accelerated depletion of non-renewable
resources such as coal and oil, will eventually necessitate much fuller use
of the world’s organic production (cf. Gaffron, 1946). To be thoroughly
efficient such utilization must be mainly a t the level of green plants,
the primary producers in the food web. It will also depend upon cheaper
sources of energy and on great expansion of biochemical engineering,
with current plant residues of all kinds serving as raw materials in
addition to the present mainstays - agricultural crops, tree boles, and
fossil plant deposits of coal and oil. Because much of the world’s land
is best suited to the growth of trees, and wood will in any case remain
a valuable raw material in its own right, forests will probably be a
major source of materials for the new biochemical technology, particularly since mature stands can in certain circumstances be managed
economically on a sustaining basis by selective felling. Moreover, forests
utilize both light and growing season to a much greater degree than
most agricultGa1 crops, especially if the trees arel evergreen. Total
yields of forest dry matter compare favorably with those of farm crops,
even without the constant cultivation and fertilization the latter receive
(Weck, 1955 ; Ovington and Pearsall, 1956; Ovington, 1956).
If forest production is to be used with maximum efficiency, the leaves
and other debris should be utilized along with boles and slash, since they
make up an important part of the total yield (see Table XX, p. 148).
One promising use of leaf litter is as a source of protein which could be
extracted from the leaves and incorporated into palatable foodstuffs.
Such protein is “not as good as milk protein, but is as good as, or even
better than, fish meal” (Pirie, 1962). Pirie (1953, 1958, 1961) has provided cogent arguments for attempting the extraction of protein from
forest and agricultural waste on a commercial scale, and the cultivation
of useful micro-organisms on the residue. The cultivation of edible
fungi on beds of forest litter or on the forest floor itself (“fungal farming”) is another use of litter which might add to the world food supply.