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to take advantage of their natural dwarfing effect built right in- 

 to the scion variety. Spur types are already available for Deli- 

 cious, Golden Delicious, Spartan and Mcintosh, the varieties of 

 real interest to New England growers. Experience with the spur 

 types on the size-controlling rootstocks, while not being encour- 

 aging, is very limited, and here again, good comparisons will re- 

 quire much work. 



Some leading nurserymen are concerned about this problem and 

 are now looking at M. robusta 5, M. robusta seedlings, and even 

 Mcintosh seedlings as understocks for the spur-types. The softwood- 

 cutting method has been perfected for the production of M. robusta 

 stocks and it is expected that this stock will be used for some 

 time to come in Eastern Canada. In our plantings at Burlington, 

 we have bearing-age spur-type Delicious on clonal M. robusta , and 

 younger trees on M. robusta seedlings, and excellent growth of the 

 scion variety has been produced. 



Other varieties, including 3 spur-types of Mcintosh and 1 of 

 Spartan, are being grown in our plots on M. robusta clonal stock. 

 Experience with M. robusta seedlings has been limited and there is 

 reluctance to work with them, partly because of the confusion that 

 is certain to follow with clonal M. robusta . M. robusta seedlings 

 from open pollinated M. robusta 5 grown here at our Research Center 

 and those grown by Prof. Ed Rasmussen, (retired) at Durham, New 

 Hampshire, have always been more vigorous than domestic seedlings. 

 At least 1 Canadian nursery and 1 domestic nursery are now trying 

 M. robusta seedlings in a limited way. 



The suitability of Mcintosh seedlings as a stock for the spur- 

 types is well worth investigation. Mcintosh seedlings produced 

 here at Burlington proved to be almost as hardy as M. robusta 5 

 clonal stock in laboratory tests. A small planting of Starkrimson 

 Delicious on Mcintosh seedlings now starting to bear in Bill Darrow 

 orchard in Putney, Vermont, has made excellent growth. A Delicious 

 planting on domestic seedlings in Shoreham, is one of the best 

 young bearing-age Delicious plantings in Vermont. 



Our Canadian collegues are working with controlled crosses to 

 produce seedlings that will hopefully be size-controlling but still 

 be adapted to a wide range of soil conditions and be cold-hardy. 

 Numerous problems have been solved in the past by using good seed- 

 lings and it is certainly possible that new seedling understocks 

 will be available in the future for New England orchards. 



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