PROGRESS REPORT: PRUNING EFFECTS ON TREE GROWTH 

 AND FRUITING OF SPARTAN APPLE 



William J. Lord and Joseph Sincuk 

 Department o£ Plant and Soil Sciences 



Small trees on size-controlling rootsto 

 omically pruned, sprayed, and harvested than 

 ling rootstocks. Nevertheless, training and 

 comes increasingly important as planting den 

 the past, we had low density orchards with s 

 seedling rootstocks which performed well on 

 types and there was little concern about tre 

 We now have low, medium and high density ore 

 and each type requires somewhat different tr 

 cedures. The trees are spur-type, standard- 

 and tree vigor varies considerably especiall 

 rootstocks because of soil types. In spite 

 trees, some growers report that pruning hour 

 creased rather than decreased. Therefore, i 

 several long-term trials to compare pruning 

 in the past. Below is a summary to date of 

 on tree growth and fruiting of Spartan apple 



cks can be more econ- 

 large trees on seed- 

 pruning of trees be- 

 sity increases. In 

 tandard-type trees on 

 a wide range of soil 

 e height and spread, 

 hards in Massachusetts 

 aining and pruning pro- 

 type or interstems, 

 y on weaker growing 

 of the trend to smaller 

 s per acre have in- 

 n 1976 we initiated 

 systems with those used 

 a study of pruning effects 

 trees . 



The Spartan apple trees on M. 7 rootstock were plante 

 Horticultural Research Center, Belchertown, }AA in 1975. 

 1976, we established the following pruning programs: (A) 

 suggested by Dr. D.R. Heinicke in USDA Agriculture Handbo 

 (Figures IB, 2), hereafter referred to as the USDA system 



in tiers and central 1 

 annually, hereafter re 

 as the tier system (Fi 



(C) minimum of pruning 

 zagging' the central 1 

 ure 4) , hereafter refe 

 the slender spindle sy 



(D) pruning as done in 

 (Figure lA) , hereafter 

 to as regular pruning, 

 trees have been pruned 

 method . 



d at the 



In February, 



a program 

 ok No. 458 

 ; (B) limbs 

 eader headed 

 ferred to 

 gure 3) ; 



and 'zig- 

 eader (Fig- 

 rred to as 

 stem; and 



the past 



referred 

 Twelve 



by each 



Fig. 1A. 



Two year old tree being pruned by standard prun- 

 ing procedures. The lowest limb should be 18 to 

 20 inches from the ground, all others spaced 4 to 

 8 inches apart vertically on the trunk and each 

 one about 90° around the trunk from the one 

 below it. 



Fig. IB. 



Two year old tree being pruned as suggested by 

 the USDA. It has 2 layers of limbs. The leader 

 will be headed annually [heavy marks ( — ) indi- 

 cate heading cuts] . The one year old wood on the 

 branches is headed annually until branches on 

 which this wood is borne start to fruit. 



