1: Columella (II, 13) justly says about manure, "Wherefore
if it is, as it would seem to be, the thing of the greatest value to
the farmer, I consider that it should be studied with the greatest
care, especially since the ancient authors, while they have not
altogether neglected it, have nevertheless discussed it with too
little elaboration." He goes on (II, 14) to lay down rules about the
compost heap which should be written in letters of gold in every farm
house.

"I appreciate that there are certain kinds of farms on which it is
impossible to keep either live stock or birds, yet even in such places
it is a lazy farmer who lacks manure: for he can collect leaves,
rubbish from the hedge rows, and droppings from the high ways: without
giving offence, and indeed earning gratitude, he can cut ferns from
his neighbour's land: and all these things he can mingle with the
sweepings of the courtyard: he can dig a pit, like that we have
counselled for the protection of stable manure, and there mix together
ashes, sewage, and straw, and indeed every waste thing which is swept
up on the place. But it is wise to bury a piece of oak wood in the
midst of this compost, for that will prevent venomous snakes from
lurking in it. This will suffice for a farm without live stock."

One can see in Flanders today the happy land smiling its appreciation
of farm management such as this, but what American farmer has yet
learned this kind of conservation of his natural resources.]

[Footnote 32: The occupants of the motor cars which now roll so swiftly
and so comfortably along the French national highway from Paris to
Tours, through the pleasant _pays de Beauce_, can see this admirable
and economical method of manuring still in practice. The sheep are
folded and fed at night, under the watchful eye of the shepherd
stretched at ease in his wheeled cabin, on the land which was ploughed
the day before.]

[Footnote 33: These of course are all legumes. The intelligent farmer
today sits under his shade tree and meditates comfortably upon the
least expensive and most profitable labour on his farm, the countless
millions of beneficent bacteria who, his willing slaves, are
ceaselessly at work during hot weather forming root tubercles on his
legumes, be it clover or cow peas, and so fixing for their lord the
free atmospheric nitrogen contained in the soil. As Macaulay would
say, "every school boy knows" now that leguminous root nodules are
endotrophi