The Effect of Number of Shoots on the Quantity and Distribution of Increment in Young Apple-trees: With three Figures in the Text

It is shown that the shoots of a young tree act additively ratherthan competitively, that is, each extra shoot produces a definiteextra increment in total weight, not that a constant incrementis divided among the shoots of the young tree. One-year apple-trees of 3 varieties were rigorously selectedfor size and weight, and in the spring disbudded to 1, 2, 3,or n, the natural number of shoots per plant. The treatmentswere applied in the 1st or 2nd year after planting and the incrementduring the treatment year was determined. Provided not morethan a few secondary shoots were produced on the current shoots,each additional primary shoot produced an increase in weight.In one variety plants with 1 primary shoot produced many secondariesand these plants were heavier than those with 2 primaries. The largest shoot was not greatly affected in size by the presenceof other shoots except in the variety which produced secondaryshoots readily. These were most abundant on plants with 1 primaryshoot, fewer on plants with 2, and almost negligible on plantswith 3 and n shoots. Treatment and varietal effects on the percentage distributionof increment as leaves, new stem, old-stem increment, and root,were small. The percentage of leaves in the 2nd year was abouthalf what it was in the 1st year; the percentage of root wasnearly the same in both years.