292 



Mineral Nutrition of Plants 



CHLOROPHYLL 



2.6 



2.4 



2.2 



^ 2.0 

 a> 



2T 1.8 

 a 



- 1.6 



c 

 <o 

 o 



a) 



Q. 



1.4 



1.0 



TOTAL 



NITROGEN 



B --o 



C ■ * 



D — -a 



E ■ 



F —a 



Sept. 



June 



July Aug. 



Sept. 



June July Aug. 



Figure 3. Leaf chlorophyll and nitrogen in leaves from Mcintosh apple 

 trees under various urea spray and nitrogen fertilizer treatments in 1947. 

 The treatments were as follows: 

 F 0.0 lb. N ground A 1.2 lb. N — 3 sprays 



B 0.6 lb. N ground D 1.2 lb. N — 3 sprays -)- 



E 1.2 lb. N ground 0.6 lb. ground 



C 2.4 lb. N— 6 sprays 



factory average nitrogen responses of Mcintosh apple trees in Western 

 New York, in the Champlain Valley some of the growth standards of 

 group 2 may be more closely correlated with the most satisfactory nitro- 

 gen responses. It also seems possible that under the high light condi- 

 tions of the Mcintosh producing area in British Columbia, the measure- 

 ments of groups 4 and 5 may be correlated with the best nitrogen 

 balance. 



