1,500 - 



3 

 XI 



d) 1,000 



u 



(0 



a. 



500 



1983 



1985 



1987 



1989 



1991 



1993 



Figure 4. Annual yield per acre from Starkspur Supreme Delicious trees on eight rootstocks. 



M.9 EMLA. This strain of M.9 performed 

 very well in this planting. Trees were preco- 

 cious and productive. Tree size was nearly 

 perfect for this spur-tj^je Delicious, and tree 

 training was almost not required. Fruit size 

 from trees on M.9 EMLA were the largest in the 

 planting in most years. Trees on M.9 EMLA 

 must be supported fully. This strain of M.9 is 

 commonly available and is one of a few strains 

 that you might have received if you ordered M.9 

 and did not specify the strain. Overall, M.9 

 EMLA is worth asking for specifically. 



M.26 EMLA. Trees on M.26 EMLA per- 

 formed well, giving relatively high yields. Tree 

 size was at the large end of the dwarf category, 

 but trees were still very manageable. As with 

 all fully dwarfing rootstocks, trees must be 

 staked. If available we would prefer 0.3 to M.26 



EMLA. 



M.27 EMLA. Starkspur Supreme Delicious 

 is too weak to propagate on M.27 EMLA. Trees 

 do not grow sufficiently to attain adequate 

 canopy volume per acre, and they do not grow 

 enough to renew fruiting wood. Trees on M.27 

 EMLA were "runted out" in just a few years 

 after planting and did not perform well. In other 

 parts of the country, M.27 EMLA has done well 

 with vigorous cultivars and in high-density, 

 fully supported plantings. 



M.9. This strain of M.9 is often referred to as 

 "dirty 9", because it has not had latent virus 

 removed from it. It was significantly smaller 

 than M.9 EMLA in this trial and performed 

 similarly to M.27 EMLA. With vigorous culti- 

 vars, it is known to perform very well in high- 

 density, fully supported plantings. 



FruH Notes, Spring, 1994 



