Note 212 — Chapter III · (continued 2)

"The roots of vegetables," says D'Héricourt, "perform the office of a perpendicular drainage analogous to that which has been practised with success in Holland and in some parts of the British Islands. This system consists in driving down three or four thousand stakes upon a hectare; the rain water filters down along the stakes, and, in certain cases, as favorable results are obtained by this method as by horizontal drains."—Annales Forestières, 1857, p. 312.