36 EXPERIMENT STATION BULLETIN 351 



Plots of well-established plants were staked out and some were treated 

 with varying concentrations of fertilizers and some with lime. Those 

 treated with nitrogen are the only plots showing any response to fertiliza- 

 tion as indicated by the vigorous growth and dark green color. None of 

 the plots treated with lime in any concentration have shown any response. 

 In conjunction with the Botany department a few plots were treated with 

 ammonium sulfamate in varying concentrations in order to determine 

 possible weed control. The ammonium sulfamate in all doses greater than 

 1/16 pounds per gallon on 100 square feet proved lethal to blueberry as 

 well as to weeds, indicating the ineffectiveness of this material as a selec- 

 tive spray. 



The department of Entomology, cooperating, reports that there 

 were no infestations of insects on bushes during the past year. 



A. F. Yeager, R. Eggert, A. R. Hodgdon, M. C. Richards, J. G. Conklin 



Improvement of the High-Bush Blueberry 



Observations of high-bush blueberry plantings of standard varieties 

 in selected areas of the state indicate a lack of soil adaptation for a suc- 

 cessful development of the high-bush blueberry in some sections. 



Varieties in the experimental plots that are making the most desirable 

 growth are on soil of somewhat porous texture. Those on clay soils are 

 making little or no growth, even though those soils are equal in fertility, 

 or higher in fertility than the lighter soils. The department of Agricul- 

 tural and Biological Chemistry, cooperating, is making a careful analysis 

 of soil samples selected from under many wild bushes that are making 

 vigorous growth. Fertilizers applied under bushes growing in clay soil 

 have given no response. An early spring application of sulphate of ammo- 

 nia on plants in sandy soils is giving excellent growth. 



R. Eggeri, a. F, Yeager 



Fruit Cultural Studies 



Mature Northern Spy apple trees with sod mulch look much better 

 than those without mulch. They are distinctly darker in color and more 

 vigorous. Young trees with a rye cover crop were nearly killed by ex- 

 cessive drying of the soil. 



L. P. Latimer, A. F. Yeager 



Varietal Trials 



Raspberry varieties which best survived this past severe winter were 

 Tahoma from the State of Washington and P78 from North Dakota. Sun- 

 rise, Chief, Ruddy and Latham showed some injury. Taylor and Indian 

 Summer killed to near the ground, and Marcy was injured still more. 

 Among the blackberry varieties Snyder and a numbered variety from the 

 New York Geneva Experiment Station were the only ones which en- 

 dured the winter without injury. Alfred is being discarded as a useful va- 

 riety because of winter injury and also because of its failure to produce 

 fruit even when not injured. Brainerd also winter kills too seriously to 

 be of any value to this section. iMost foreign plant introductions proved 

 to lack hardiness, although Plant Industry #136141, n/biis thyrsoides 



