A COMPARISON OF TREE SIZE, PRODUCTIVITY AND FRUIT 

 QUALITY OF DELICIOUS STRAINS 



W.J. Lord, F.W. Southwick, R.A. Damon, Jr., and J.F. Anderson 



The performance o£ Delicious strains at the Horticultural 

 Research Center was discussed in a previous issue of FRUIT NOTES 

 (Vol. 44, No. 6). Information reported here includes 1979 findings 

 and data previously not presented. 



Experimental Design 



A planting was established in 1964 at the Horticultural Research 

 Center, Belchertown, MA to evaluate the following Delicious strains 

 on M7 rootstock: Richared, Turner Red, Jardine Red, Royal Red, 

 Gardiner Red, Red Prince, Rogers Red, Sturdeespur (Miller Strain), 

 and Starkrimson (Bisbee Strain), the last two being spurs. The experi 

 ment was a randomized block design with 6 single-tree replicates. 

 The trees were planted at 20 feet by 30 feet spacing. Summarized 

 below are our findings to date. 



Tree Size 



The trunk cross-sectional areas of the trees with the standard- 

 type growth habit were similar and about twice as large as those of 

 the spur strains (Table 1) . 



Table 1. Mean size of the 7 standard and 2 spur strains of Delicious, 

 1979. 



Growth Trunk cross- 2 Tree Tree 



habit sectional area (cm ) height (ft) spread (ft) 



Standard 342 13 19 



Spur 173 12 14 



The difference in tree height was not large because commencing in 

 1977 we restricted height on the standard strains. Of particular 

 interest to note is that we could have allowed 5 feet less spacing 

 in-the-row and between- the-row for the spur trees than the standard 

 trees without encountering tree crowding. 



No limb spreaders were used when the trees were young. This 

 practice, which has recently been adapted almost universally, may 

 have altered tree spread and productivity. Branches of spur strains 

 are more upright growing than those on standard strains, but our 

 differences are much less striking than what have been illustrated 

 in some publications and what we have observed in some other orchards. 



