Our association with
plants predates our human condition. Although the appreciation of plants by
humans is probably innate, the ability to exploit plants so successfully is
in large part a result of humankinds capacity to transmit knowledge culturally.
Of all the various plant groups - algae, mosses, ferns, gymnosperms
and flowering plants - Flowering plants have furnished us with nearly all of
the species we use for food and clothing and in countless other ways. Since
the flowering plants, or angiosperms, comprise nearly two-thirds of all species
of plants and are the dominant vegetation on the earth's land surface, their
great use perhaps should not come as a surprise; but their significance does
not derive as much from their numbers as from the fact that they are the only
plants that produce fruits and seeds. Of the 250,000 or more species of known
flowering plants, it has been estimated that there are about 30,000 edible plant
species, however only 3000 or so have historically been used to any extent by
humans for food. Of these about 200 have become more or less domesticated, and
entered into modern world commerce.
This trend has led to our present situation, in which only about
20 species, all highly modified by humans, are of major economic importance.
Only about dozen species or so are the primary foods that stand between us and
starvation. The grasses are foremost in this regard (Figure 1). Of the 300 or
so families of flowering plants, none is of greater importance to us than the
grass family, known scientifically as the family Gramineae (Heiser, C. B., 1973.
Seed to Civilization: the Story of Food, Harvard University Press,
Food from Fungi. Frank A. Gilbert and Radcliffe F. Robinson. Economic Botany.
Volume 11. pp. 126-145.
Bryophytes as Economic Plants. John W. Thieret. Economic Botany. Volume 10.
Economic Uses of Lichens. George A. Llano. Economic Botany. Volume 2. pp. 15-45.
Agriculutral Crop Statistics