If there are uneven places on the sodded area, these depressions can be filled in with very loose, fine soil; and the grass will grow through it. In dry weather, a sodded area may be mulched with a half inch of fine loam to protect it.
SOILS. Soils are of many kinds. The classification of soils depends upon one’s point of view. Gardeners ordinarily call a good, friable, dark-colored, rich Soil a garden loam. No Soil is so good that it cannot be improved. It is improved in two general ways: by tilling (see _Tillage_), and by the application of various substances.
In considering the improvement of lands by the application of foreign substances, two distinct things are to be considered: the improvement of the physical texture, or tilth, of the Soil; the increasing of its plant-food. These are coördinate objects. In some cases one may be of prime importance, and in another case the other may be more necessary. Lands which have a fair store of available plant-food may be unproductive. Such lands may be very greatly benefited by stable manure, even though that manure may have lost a large part of fertility by being baptized under the eaves of the barn. If plant-food alone is needed, then some concentrated or commercial fertilizer may be the best thing to apply. In most cases the main or chief amelioration of the land is to be wrought by tillage, stable manures, mulches, green crops, and the like; if special results are desired, commercial fertilizers may be added more or less liberally, as the case demands (see _Manures_, _Fertilizers_).
The top-dressing of Soils is often very beneficial because it tends to prevent the escape of moisture, and often improves the physical texture. If the material contains plant-food, the land will also be directly enriched. The trimmings from lawns may be a distinct protection to lands if allowed to remain (see _Lawns_); and the leaves which blow into clumps of shrubbery may often be allowed to remain with good results. However, if the leaves become too thick year after year, they tend to induce a surface rooting of the shrubs. This, however, may be no disadvantage unless the mulch were finally to be removed. One of the very best top-dressings for borders and shrubbery is spent tan bark, since it does not pile up on the ground, but tends to work into it. Well-rotted sawdust often has the same effect. These materials are much used by gardeners, when they can be had, since they can be raked into the soil in the spring, and need not be removed.