EMLA also were very productive on a per acre 

 basis. Averaged over the last five years, trees on 

 MAC.9, 0.3, M.9 EMLA, M.26 EMLA, and M.7 

 EMLA produced annually 940, 840, 830, 730, 

 and 680 bushels per acre, respectively. Over the 

 same period, trees on M.27 EMLA produced 

 only 310 bushels per acre annually. Table 2 

 presents cumulative )deld per acre. Trees on 

 MAC.9 produced 8270 bushels on a per acre 

 basis over the life of the planting. Trees on M.9 

 EMLA and 0.3 produced 6290 and 6140 bush- 

 els, respectively. Trees on M.27 EMLA pro- 

 duced only 2770 bushels per acre, partly be- 

 cause of inadequate canopy height and there- 

 fore small bearing surface per acre. 



Conclusions 



Several conclusions about specific 

 rootstocks can be made from this study. First, 

 however, it must be emphasized that these data 

 were collected fi-om Starkspur Supreme Deli- 

 cious, a low-vigor cultivar, and some results 

 may have been different with a more vigorous 

 cultivar such as Mcintosh. Secondly, some of 

 the conclusions must be tempered by results 



obtained in other locations. 



0.3. This rootstock performed very well. It 

 was relatively precocious, and produced high 

 3delds over the fourteen-year life of the planting. 

 Tree size was slightly smaller than M.26 

 EMLA, so trees were very manageable. Fruit 

 size was large from trees on 0.3. Even though 

 most of the trees in this planting were not 

 staked, staking should be considered a require- 

 ment with 0.3. One problem with 0.3 is that it 

 is of limited availability, because it is so difficult 

 to propagate. Specifically, it does notdevelop 

 roots very readily in the stool bed. Some work 

 suggests that this problem may be overcome in 

 the nursery, but has not yet resulted in a signifi- 

 cant quantity of 0.3. Overall, it is a rootstock 

 very much worthy of trial if you can get it. 



M.7 EMLA. This rootstock performed very 

 well with a spur-type Delicious as a scion. It was 

 somewhat more precocious than normally ob- 

 served. Generally, it was not as productive as 

 0.3, M.9 EMLA, and Mark, but still performed 

 very well. Trees are vigorous and do not lend 

 themselves to high-density planting, but it is 

 probably still the best choice for a free-standing, 

 semidwarf tree. 



Fruit Notes, Spring, 1994 



