9. 



The peach orchard set in 1980 has 15 peach and 6 nectarine 

 varieties under evaluation. Five pear varieties have been added 

 for evaluation in the past 2 years. Additional pear varieties 

 will be set next spring. 



Small fruit varieties and selections are also evaluated at 

 the Research Center. The emphasis has been on strawberry variety 

 evaluation in recent years. This past summer, 9 numbered selections 

 and about 10 varieties were evaluated. Scott a newly released var- 

 iety from the U.S.D.A. was evaluated for 4 seasons and will be 

 recommended for trial planting in Massachusetts. Several grape 

 varieties that show promise are Alden, Lakemont and Steuben. 



******* A ******:% A A*** 



IV. Adaptability of apple tree rootstocks to representative or - 

 chard soils in Massachusetts . Peter L. Veneman 



Several new rootstocks have been introduced during the last 

 few decades and claims pertaining to their adaptability to various 

 environmental conditions sometimes have been contradicting and 

 confusing. These claims as well as statements regarding the "old" 

 rootstocks (M9, M7 , M26, MM106 and MMlll) often are not based on 

 reliable field trials. Observations by pomologists and commercial 

 fruit growers indicate that local differences in soil type pro- 

 bably are largely responsible for variations in growth of apple 

 trees on particular kinds of rootstocks. An evaluation of the 

 effects of different environments on apple tree growth seemed 

 justified and several studies were initiated to research this 

 interaction. Following is a brief description of the various 

 soil- rootstock research projects and a synopsis of this year's 

 progress . 



Size-control rootstocks are, in general, more demanding than 

 seedling rootstocks in respect to drainage, depth of soils and 

 water holding capacity. When choosing which rootstock to use it 

 is important to have a proper understanding of the particular 

 rootstock-soil type interaction. The right match between rootstock 

 and soil may be the difference between commercial success or fail- 

 ure of the planting. A wide variety of different soil types is 

 used in Massachusetts for growing apple trees. It is impossible 

 to do an experimental planting on each different soil type but the 

 most commonly used soils are closely related, which allows extra- 

 polation of the results of a limited number of research sites to 

 most Massachusetts and New England conditions. This project con- 

 sists of two stages, one of which is concerned with the carefully 

 monitored growth of selected rootstocks on 9 representative or- 

 chard soils. The second stage involves the evaluation of the 

 growth of the different size controlled rootstocks as related to 



