“Well, to some extent they injure the soil because they tend to destroy the limestone and increase the acidity of the soil, and also because they contain more or less manufactured land-plaster and thus serve as soil stimulants; but the chief point to keep in mind concerning the use of the common so-called complete commercial fertilizer is that they are too expensive to permit their use in sufficient quantities to positively enrich the soil.  Thus the farmer may apply two hundred pounds of such a fertilizer at a cost of $3.00 an acre, and then harvest a crop of wheat, two crops of hay, pasture for another year or two, plow up the grounds for corn, apply another two hundred pounds for the corn crop, follow with a crop of oats, and then repeat.  He thus harvests five crops and pastures a year or two and applies perhaps four hundred pounds of fertilizer at a cost of $6.00.

“As an average of the most common commercial fertilizers sold to the farmers in the Eastern and Southern States, the four hundred pounds would add to the soil seven pounds of nitrogen, fourteen pounds of phosphorus and seven pounds of potassium, while a single fifty-bushel crop of corn will remove from the soil ten times as much nitrogen, five times as much potassium, and nearly as much phosphorus as the total amounts applied in this six-year or seven-year rotation.

“In this manner the farmer extends the time during which he can take from the soil crops whose value exceed their cost.  He applies only one-fourth or possibly one-half as much of the most deficient element as the crops harvested require, and thus he continues for a longer time to ’work the land for all that’s in it! ’”

“Well, isn’t that the limit?” said Adelaide, with emphasis on the “isn’t,” for which she received a disapproving look from her mother, so far as her almost angel-face could give such a look.

“So far as human ingenuity has yet devised,” replied Percy, “this system appears to be the limit; but this limit has not yet been reached on any Westover soil.  If anyone can devise a method for extending this limit he should apply it on a type of soil covering more than two-fifths of the total area of St. Mary County and more than 45,000 acres of Prince George County, Maryland, some of which almost adjoins the District of Columbia.  This soil has been reduced in fertility until it contains only one-third as much phosphorus as your poorest land.  I found a Western man who had come down to Maryland a few years ago.  He saw that beautiful almost level upland soil, and it looked so good to him that he bought and kept buying until he had ‘squared out’ a tract of eleven hundred acres.  He still had left money enough to fence the farm and to put the buildings in good repair.  He was a live-stock farmer from the West who just knew from his own experience and from that of the Secretary of Agriculture, in the use of a little clover or farm manure in unlocking the great reserves of an almost virgin soil, that all his Maryland farm needed was clover seed and live stock.  Sheep especially he knew to be great producers of fertility.