BORON CONTENT OF APPLES AT DIFFERENT STAGES OF DEVELOPMENT

In view of the current interest in boron as one of the elements essential for the normal growth of plants, and as a factor concerned in the occurrence of physiological disorders of the apple, the writers have determined the boron content of this fruit at various stages in its development. The material used was fruit of the variety Golden Russet originally collected by one of us (DELONG) for another purpose. This fruit was apparently normal in all respects and quite unaffected by any physiological disorders. Dates of collection and other descriptive data are given in table I. It should be noted that all of the samiples are composite, approximately equal numbers of fruits having been gathered from each of several trees at each collection. These trees were of uniform age, all in a vigorous condition, and bore, in the season of collection, fair to good crops of fruit. The orchard soil is a sandy loam with a clay subsoil. The orchard is not cultivated, but the weed-grass growth is clipped in June. The chief fertilizer used is barnyard manure.