-5- 



In 1978 soil treated with NH^NO^ for 7 consecutive years had 

 less exchangeable Ca and Mg than untreated soil from between 

 the trees. In contrast exchangeable Ca was similar in untreated 

 soil and in soil fertilized with KNO^ or Ca(NO,)^. Soil K was 

 higher under the trees than between the trees out N source did 

 not influence K, which had been applied equivalently under all 

 trees . 



the 



The 

 el imi 

 or 



NH^NOj 

 secut ive 

 those obt 

 tially in 

 our study 

 tree and 

 applied i 



original experimental design was changed in 1980 with 

 nation of the KNO, treatment but with the continuation of 



i(N0,)2 applications. Our data in 1981 after 10 con- 

 annual applications of Ca(N0,)2 are in agreement with 

 ained in 1978 (Table 1) in tnat its use has not substan- 

 creased the amount of exchangeable Ca in the soil. Thus, 

 continues to emphasize the difficulty of affecting soil, 

 fruit Ca when fertilizing with CaCN0,)2 because the amount 



s small when it is based on the N needs of the trees. 



******* 



PRELIMINARY FINDINGS FROM THE MULTI -STATE 

 COOPERATIVE APPLE INTERSTEM PLANTING-"- ' ^ 



William J . Lord 

 Department of Plant and Soil Sciences 



The preliminary results from a cooperative interstem plant- 

 ing established in 10 states in 1976 are published in the Fruit 

 Varieties Journal, 1982 (Vol. 36, No. 1) and authored by David 

 Ferree of the Ohio Agricultural Research and Development Center, 

 Wooster, Ohio. The purpose of this multi-state planting is to 

 study the growth and yield potential of 2 scion cultivars with 

 an M9 interstem for dwarfing on 3 vigorous rootstocks under a 

 diversity of climatic conditions. 



Trees for the plantings were propagated by double grafting 

 a 6-inch stempiece of M9 on scions of Sturdeespur Delicious or 

 Empire and on rootstocks of MMlll, Ottawa II or Antonovka Seed- 

 lings. Ottawa II and Antonovka rootstocks were selected because 

 they provide good anchorage and cold hardiness. MMlll served as 

 the control. This rootstock has shown good soil adaptability 

 but lacks precocity when used as the understock on 2-piece trees, 



States cooperating in this study were Illinois, Indiana, Iowa, 

 Kansas, Kentucky, Massachusetts, Michigan, Missouri, Ohio and 

 Wiscons in. 



Editors Note. The trees for the Massachusetts planting were 

 exceptionally poor, causing tree loss the year of planting, poor 

 growth of surviving trees and lack of fruitfulness . Other inter- 

 stem trees were planted on this site in 1979, and no tree loss 

 has been experienced and growth is vigorous. 



