Much has been said and written on the subject of conservation and many excellent ideas have been advanced, but as yet too little has been accomplished in the way of practical results. Probably this is due largely to the fact that most people think of conservation as a problem for the federal and state governments, mine owners, great lumber companies, owners of vast tracts of land, and large corporations; and have not realized how much the responsibility for the care of our natural resources and the penalty for their waste rest with the whole people, that every one has a part in this work which has been called ''the greatest question before the American people.''
Some waste of this upper layer is constantly taking place from above, caused by wind and floods, and considerable additions are made to it by the decay of animal and vegetable matter, but in order to keep the soil at its best, the average soil waste should not amount to more than an inch every thousand years.
When this humus is once exhausted there is no way to repair the damage but to wait for the slow rock-decay. In the river valleys there is no immediate danger of exhausting the entire body of the soil, but on the hills and in the higher regions the soil-depth is very much less than four feet, and the danger of waste much more serious. There are parts of the earth that were once almost as fertile as ours where great cities once stood, but where now nothing is left but the bare rock.
So we know that the end is sure, even for the life of man upon earth, unless we learn to conserve our soil.
The value of our farm crops can not be overestimated. In food value they are