sachusetts Horticultural Research Center 

 (Belchertown). Each of these sites clearly in- 

 cluded overly vigorous trees. Trees used at Fay 

 Mountain Farm were mature Mcintosh/ 

 MM. 106, those at Rice Fruit Farm were mature 

 Cortland/M.7, and trees at the Horticultural 

 Research Center were mature Gardiner Deli- 

 cious/MM.106. At Fay Mountain Farm and Rice 

 Fruit Farm, trees were partitioned into four 

 blocks. Approximately half of each block was 

 root pruned on May 13, 1991 (4 to 8 days after 

 petal fall) with a "Phil Brown Welding" root 

 pruner. Both sides of the tree row were root 

 pruned. Trees at the Horticultural Research 

 Center were pruned similarly, but only a single 

 tree in each of seven blocks was pruned. Fruit 

 drop was assessed periodically throughout the 

 harvest season, and the length, diameter, and 

 weight of terminal growth was measured during 

 the winter. 



1991 Results 



Table 1 shows the effects of root pruning on 



shoot growth. Shoot growth clearly was reduced 

 at Fay Mountain Farm and Rice Fruit Farm; 

 however, no effect was measured at the Horti- 

 cultural Research Center. It is puzzling why 

 root pruning significantly reduced growth at 

 two locations and not the other. One possible 

 explanation may be the soil conditions at the 

 Horticultural Research Center (the site is rela- 

 tively wet), or the discrepancy could relate to the 

 cultivars, that is, Delicious at the Horticultural 

 Research Center and Cortland and Mcintosh at 

 the other sites. We have repeated the experi- 

 ment at the Horticultural Research Center this 

 year in the same block, but using Mcintosh trees 

 rather than Delicious trees. 



Figures l,2,and3showfruitdropduringthe 

 harvest season at Rice Fruit Farm, Fay Moun- 

 tain Farm, and the Horticultural Research Cen- 

 ter, respectively. Clearly, root pruning resulted 

 in significant reductions in drop at Rice Fruit 

 Farm and Fay Mountain Farm; however, as 

 with growth, there was no effect on drop at the 

 Horticultural Research Center (possibly for the 

 same reasons as mentioned above). 



Fruit Notes, Summer, 1992 



