EXPERIMENT STATION WORK WITH PEACHES. 411 



most part, however, they produced a good crop of healthy, well- 

 sized, well-colored foliage and made a very fair recovery. The obser- 

 vations with peaches and other fi'uits indicate that it is extremeh' 

 difficult to tell b}^ any ordinarj^ method of examination the real condi- 

 tion of trees at the end of a winter season and their ability to over- 

 come winter injury. 



Experiments were made by the station in pruning back the winter- 

 injured trees to different degrees as a means of rejuvenation. Some 

 trees were given a moderate amount of pruning, some were not pruned 

 at all, others were cut back to the large limbs or "dehorned," and in 

 some instances, yovmg trees were cut off below the snow line. In the 

 station experiments when peach trees 7 or 8 years old or older were 

 cut back to where the limbs were H to 2 inches in diameter, or 

 "dehorned," they failed to recover, and by the following September 

 all were dead. 



On the other hand, 3"oung peach trees 2 to 5 years old thus treated 

 made a splendid recovery, and trees thus primed back in January 

 made a better growth than when the cutting back was deferred until 

 March. Young trees in the same orchard not pruned at all either 

 died outright or the new growth was mostly in the top, making an 

 undesirable tree. One of the objections to pruning young peach trees 

 back so severely was that it induced a too great growth of young 

 wood which formed a bushy top and necessitated a great deal of 

 additional pruning. 



In the orchards of both old and young trees a moderate amount of 

 pruning back was compared with no pruning and with "dehorning." 

 Trees moderately pruned made in every instance a much better growth 

 than those not pruned at all. Old trees which died when ' ' dehorned ' ' 

 recovered when only moderately pruned. 



Much the larger number of injured trees were not pruned at all, 

 and, while many of these made a recovery which was satisf actor}" to 

 the grower, it was evident that the average condition of these trees 

 was not nearly so good as when they were given a moderate pruning. 

 The young pruned trees contained a much larger amount of dead 

 wood and the new growth was much more generally at the extreme 

 ends of the branches, which made the top of the tree too spreading. 



The Michigan Station also reports ° that severe priming of winter- 

 injured trees — that is, cutting back to wood l^ to 2 inches in diam- 

 eter — proved dangerous to the life of the trees. Moderately pruning, 

 or cutting back to wood one-half to three-fourths of an inch in diame- 

 ter, gave better results than light pruning in the usual way. It 

 appears that in the Michigan experiments trees lightly pruned after 

 the usual plan of heading in and thinning out part of the new growth, 

 grew more slowly, produced smaller, less thrifty foliage, smaller fruit 



a Michigan Sta. Bui. 177; Bui. 187; Spl. Bui. 11. 



