No. 2, March, 1921] HORTICULTURE 145 



tilizer treatments, it would be well to keep yield records for two or, even better, three years 

 on the different plots before applying the fertilizer. It is stated that the partial failure of 

 some of the early experiments should not discourage the continuance of such a fundamental 

 line of investigation, and that pomological research will be improved by the passing out of 

 the old types of fertilizer experiment. — E. C. Auchter. 



954. Auchter, E. C. Some influences of thinning, pollination, and fruit spur growthon 

 the yearly performance record of fruit spurs and on the size of fruit produced. Proc. Amer. 

 Soc. Kort. Sci. 16: 118-131. (1919) 1920.— Investigations in apple thinning, pollination, and 

 fruit-spur growth were carried on from 1912 to 1919, inclusive, at the West Virginia Experi- 

 ment Station. Results of the studies were as follows: (1) Apple-thinning experiments, car- 

 ried on from 1912 to 1919, inclusive, show that neither the tree as a whole nor the individual 

 fruit spurs are influenced by the removal of part of the crop so that the tree or spurs bloom 

 again the following season. Fruit thinning, then, does not affect the annual bearing of 

 apple trees.— (2) The size of the individual specimens left on the tree after thinning is greatly 

 increased during the same year as a result of the removal by thinning of part of the crop. 

 More marketable fruit is produced by the thinned trees and increased size of each apple in 

 cases where the trees are bearing a good crop of fruit. This influence on size is lessened or 

 lost altogether when trees are bearing light crops.— (3) The spurs on certain varieties of 

 apples bloom more regularly than those of other varieties, but this does not mean that such 

 spurs and varieties bear more regularly. A more likely explanation, with reference to fruit 

 spurs only, of why certain varieties are annual bearers, is given in Nos. 7 and 8. — (4) 

 Spurs which set fruit one year, generally do not blossom the next year. — (5) Spurs which 

 blossom one year but do not set fruit, often blossom the next year. Others do not however. — 

 (6) These results indicate for the varieties studied that the spurs, which blossom two years in 

 succession make a greater yearly growth, have more leaves and a greater total leaf area in 

 the year preceding the second successive blooming year. Such spurs have a greater total 

 length and thus all indications show that they are more vigorous. Thus growth and vigor 

 to a certain degree do not oppose, but rather encourage, fruitfulness. — (7) These results indi- 

 cate that a variety is not an annual bearer because the same spurs bear in succession. They 

 indicate that either a certain percentage of the total spurs on such varieties do not bloom 

 in the heavy crop year and thus such spurs bloom and set fruit in the next year, or if all the 

 spurs do bloom, a certain percentage of the spurs do not set and thus more readily bloom 

 and set the next year.- (8) These results suggest that probably a larger proportion of the 

 spurs on the biennial bearers not only bloom, but also set fruit in the crop year. Such 

 spurs then do not readily bloom the next year. Observation shows that trees bearing heavy 

 crops make very little spur growth during such years. We would expect then from No. 6 

 that very few spurs on such trees would bloom the following year. If greater spur growth 

 was s,ecured on the annual bearing varieties, then, a greater proportion of spurs would bloom 

 in the off year, especially the non-blooming spurs of the year before.— (9) Certain varieties 

 which produce fruit yearly, form fruit buds terminally and laterally on one year old 

 growths to such an extent that the production of fruit from these sources is often enough to 

 class a variety as an annual bearer without reference to its fruit spurs. It is also possible 

 that some varieties produce a higher percentage of fruit spurs yearly than do others, and as 

 these gradually form fruit buds, some annual fruit may be produced. However, there are 

 many so-called annual bearers that do not produce fruit by any of these methods and a more 

 reasonable explanation of their annual bearing is given in Nos. 7 and 8. — (10) If the state- 

 ments under Nos. 7 and 8 finally prove to be justified in later work, then the whole prob- 

 lem of biennial and annual bearing appears to be affected to a degree by the sterility and 

 pollination problem and is not one of growth and nutrition only. — (11) It may be possible 

 to break up the biennial bearing of certain varieties of apples either by altering certain 

 cultural, fertilizer, or pruning methods as suggested by different investigators, and after 

 seeing what light certain pollination studies may throw on the problem, but at this time, 

 we have no definite information to offer on this point, based upon investigational work of 

 this station.— (12) There appears to be a good correlation between the weight of the indi- 



