Renovation of Old Groves.
Material improvement of old plantations may sometimes be effected and, unless the trees are known to be upward of fifty years old, generally repays the labor. Marked increase in crop has followed a heavy thinning out of trees upon the Government cocoanut farm at San Ramon, Mindanao. The improvement that a freer circulation of air and abundant sunlight have effected is very marked. Where it can be done, plowing is also sometimes feasible and should be followed by immediate crop improvement. The average native plow is not so well adapted for working over an old or neglected grove as it is for original soil preparation. It acts more as a subsoiler and will tear and lacerate more roots than is desirable. A single carabao, or one-horse American garden plow, is the better implement for this work. Extensive bat guano deposits are found in Mindoro, Guimarás, and Luzon. Some of them show richness in nitrogen and, when accessible at a moderate cost, would be useful in the renovation of old groves, where the shade would be adverse to the rearing of good crops of nitrogen gatherers.