“What we want to find out is, why the clover can get so much more phosphoric acid, potash, and nitrogen, than the wheat, from the same soil?”
MORE ABOUT CLOVER.
The Deacon seemed to think the Doctor was going to give a scientific answer to the question. “If the clover can get more nitrogen, phosphoric acid, and potash, from the same soil than wheat,” said he, “why not accept the fact, and act accordingly? You scientific gentlemen want to explain everything, and sometimes make confusion worse confounded. We know that a sheep will grow fat in a pasture where a cow would starve.”
“True,” said the Doctor, “and that is because the cow gathers food with her tongue, and must have the grass long enough for her to get hold of it; while a sheep picks up the grass with her teeth and gums, and, consequently, the sheep can eat the grass down into the very ground.”
“Very well,” said the Deacon; “and how do you know but that the roots of the clover gather up their food sheep-fashion, while the wheat-roots eat like a cow?”
“That is not a very scientific way of putting it,” said the Doctor; “but I am inclined to think the Deacon has the right idea.”
“Perhaps, then,” said I, “we had better let it go at that until we get more light on the subject. We must conclude that the wheat can not get food enough from the soil to yield a maximum crop, not because there is not food enough in the field, but the roots of the wheat are so constituted that they can not gather it up; while clover-roots, foraging in the same soil, can find all they want.”
“Clover,” said the Deacon, “is the scavenger of the farm; like a pig, it gathers up what would otherwise be wasted.”
“Of course, these illustrations,” said the Doctor, “do not give us any clear idea of how the clover-plants take up food. We must recollect that the roots of plants take up their food in solution; and it has just occurred to me that, possibly, Mr. Lawes’ experiments on the amount of water given off by plants during their growth, may throw some light on the subject we are discussing.”