Do all soils contain enough lime for the use of plants?
What amount is needed for this purpose?
What is its first-named effect on the soil?
Its second? Third? Fourth? Fifth?
How are acids produced in the soil?
As food for plants, lime is of considerable importance. All plants contain lime—some of them in large quantities. It is an important constituent of straw, meadow hay, leaves of fruit trees, peas, beans, and turnips. It constitutes more than one third of the ash of red clover. Many soils contain lime enough for the use of plants, in others it is deficient, and must be supplied artificially before they can produce good crops of those plants of which lime is an important ingredient. The only way in which the exact quantity of lime in the soil can be ascertained is by chemical analysis. However, the amount required for the mere feeding plants is not large, (much less than one per cent.), but lime is often necessary for other purposes; and setting aside, for the present, its feeding action, we will examine its various effects on the mechanical and chemical condition of the soil.
1. It corrects acidity (sourness).
2. It hastens the decomposition of the organic matter in the soil.
3. It causes the mineral particles of the soil to crumble.
4. By producing the above effects, it prepares the constituents of the soil for assimilation by plants.