]STew York Agricultural Experiment Station. 463 



respects would produce trees that are early bearers, or more 

 regular in bearing or more fruitful. The present trend of science 

 is against such a possibility. Even were it possible, there are a 

 number of practical drawbacks. 



Thus, from tree generation to tree generation constitutes a 

 period of time too long for most men to bend their efforts, espe- 

 cially with that clear conception of exactly what is wanted that 

 is required in the intricate problem of plant selection. The varia- 

 tions at best, are but slight and hundreds of trees would have to 

 be examined to find one or two from which to start a new race. 

 One would have to make sure, too, that the selected plants would 

 not fall behind their fellows in other characters. The variations 

 mentioned are almost certainly the result of environment and 

 are not passed on from one tree generation to another so that, 

 even were the obstacles not so great in practicing selection that 

 few men would be able, or would take the pains to surmount 

 them, heredity could not be counted as a factor in causing the 

 formation of buds. 



Another phase of the subject of fruit-bud control is the biennial 

 bearing habit of some varieties of the several fruits and especially 

 of the apple. So marked is this habit in apples that we can 

 ascribe it as one of the characters of that fruit. A good deal of 

 attention has been given by orchardists and experimenters to 

 biennial bearing in apples but as yet no one has been able greatly 

 to change nature's way. It is maintained by some that the 

 biennial bearing habit is due to the heavy crop which exhausts the 

 tree's energies and that a light crop follows because of such ex- 

 haustion. This can be but partly true; for all can call to mind 

 two, three, or four heavy crops of some varieties after which the 

 trees settle down to bearing in alternate years. 



ISTor does thinning, often proposed as a remedy for over-bear- 

 ing, prove of much value. Pruning seems to alter the condition 

 but little. \Ye have on record several experiments in which blos- 

 soms were stripped from the trees during the bearing year to 

 cause the setting of fruit during the off year. The trees so treated 

 usually bear some fruit the off year but seldom a satisfactory 

 crop. Xor is the matter one of food supply. Orchards amply 

 supplied with food are not always annual bearers, l^eeuliarities 

 of the season have something to do with alternate bearing but do 

 not wholly account for it. Eliminating all the above conditions — 

 admitting, however, that all have some influence on the bearing 

 habit — we must conclude that the biennial bearing habit of 



