34 Experiment Station Bulletin 363 



of sap flow. Butternut yielded a small amount of sap; Yellow Birch and 

 Black Birch produced somewhat more, while Gray Birch flowed freely 

 and for a longer period. 



C. L. Stevens, Stuart Dunn 



Plantation Studies 



Analysis of the periodical measurements of height growth of 400 

 sample trees in white pine plantations, some of them covering a period 

 of five years, indicate that when using four-year-old transplants, trees 

 less than nine inches in height should not be included in the planting 

 stock. Trees over 18 inches tall are likely to show a mortality rate nearly 

 double that of the smaller sizes, and should either be thrown out at plant- 

 ing time, or given especial care in planting. During the next few years 

 the validity of this conclusion will be tested further. 



C. L. Stevens 



FRUIT PRODUCTION 



Coloring of Picked Apples 



Samples of 100 Mcintosh, Baldwin, and Yellow Bellflower apples 

 w^ere selected from single trees. Half of each sample was subjected to a 

 fine mist of cold water during hours of sunshine for comparison with un- 

 sprayed controls. 



Temperatures in sprayed fruits were from 18° to 33°F cooler dur- 

 ing the warmest period of each day than were those of unsprayed fruits. 

 Also, sprayed fruit started to color sooner than the unsprayed. How- 

 ever, after eight hours in bright sunshine, color gradually disappeared 

 from the upper surfaces of the sprayed fruit, and in an additional eight 

 hours the areas became increasingly brown in color. 



These experiments show that surfaces of picked apples exposed to 

 bright sunshine may be injured within eight hours. Such injury is not 

 due to high temperatures and could occur on cool, clear days as well as on 

 warm days. 



The sprayed fruit stored well but was obviously unmarketable. 



Russell Eggert 



Leaf Scorch in Deciduous Fruit Plantings 



Soil was obtained under Mcintosh apple trees affected severely with 

 scorch and treated in the greenhouse with (1) magnesium sulphate, 100 

 pounds per acre; (2) calcium limestone, two tons per acre; (3) magne- 

 sium limestone, two tons per acre; (4) control. Four replications were 

 made of these treatments. All plots, including the control, received ni- 

 trogen in solution as 5-0-0 at the rate of 800 pounds per acre. As with 

 turnips under previous similar treatment, no effect on growth resulted 

 from magnesium applications. Growth with both lime treatments was 

 not only greater, but reproductive organs appeared at an earlier date. 

 The yield of ears of corn with calcium and magnesium-lime treatments 

 was double that with the control or with magnesium sulphate. No scorch 



