But those nations were by no means so weak and defenceless as the miserable and helpless Americans; and in proportion to the natural fertility of the countries which they inhabited, they were, besides, much more populous.
Planting and tillage frequently regulate more than they animate the active fertility of Nature; and after all their labour, a great part of the work always remains to be done by her.
The field has lost its fertility, and I have struggled with successive optimistic plantings of beans and squash and cucumbers and even, hopeful folly on that neglected soil, young orange trees.
Once you throw off those conditions in which coffee has evolved over millennia, it throws off flavor, it throws off the abundance and fertility of the crop.
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Eventually, however, the extra work begins to increase output less and less, until additional workers add nothing further to production, because the fertility of the soil is exhausted.
Two years at a time, our land is in green manure, which is where it's basically regenerating and building fertility, restoring health after many years of arable production.
If, then, the peculiar distribution of sequoia has not been governed by superior conditions of soil as to fertility or moisture, by what has it been governed?