H. BOTANY AND HORTICULTURE. 353 



H. BOTANY AND HORTICULTURE. 



WHY THE WINTER OF 1871-72 WAS INJUEIOUS TO YEGE- 



TATIOX. 



The transactions of the Massachusetts Horticultural Soci- 

 ety contain a recent report from prominent Boston horticult- 

 urists upon this subject. The causes combining to produce 

 the results were the unprecedented drouths of the two pre- 

 ceding summers, enfeebling tlie roots, and preventing strong 

 and vigorous growth; the want of snow, and the severe cold 

 of the winter freezing the ground to an unusual depth ; con- 

 tinued and violent winds, causing a constant evaporation of 

 sap, which the roots Avere unable to replace ; and sudden and 

 extreme alternations of heat and cold. Evero-reens suffered 

 most severely, for two reasons : because their roots are for the 

 most part near the surface, and because, unlike deciduous 

 trees, they are never completely at rest, and require a certain 

 amount of sap to maintain their foliage. Hence the evapo- 

 rative action of the winds Avas peculiarly injurious to them, 

 and hence, also, they the more readily succumbed to the sud- 

 den intense cold of March, following some days of warm 

 weather, which had excited their leaves to as great activity 

 as was possible at the season. 



This reasoning is confirmed by the experience of the past 

 season, which has been the direct reverse of the preceding 

 one a wet, warm summer, a moderately warm autumn, a 

 well -ripened grow^th, a constant and abundant covering of 

 snow during the Avinter, though with a degree of cold almost 

 unprecedented. As the result, evergreens never have done 

 better; Avhile, owing to the small amount of frost in the 

 ground, the roots of deciduous trees have been unusually 

 active, the movement of the sap throwing forward the buds, 

 which, in the case of fruit-trees, appear to be in many in- 

 stances killed. Trans. Mass. Hort. Soc, March^ 1873. 



DISTEIBUTIOX OF SEEDS BY AVIXDS. 



Mr. Alfred W. Bennett has called attention to the compar- 

 atively little-known article by Kerner upon the influence of 



