﻿WHITE PINE UNDER EOKEST MANAGEMENT. 



17 



penetrate into it the subsoil becomes more and more important in 

 the growth of the tree. Its roots once well established in fertile, 

 moist soil, future growth of the seedling depends very largely upon the 

 character of the vegetation surrounding it. In hot', exposed situa- 

 tions it needs, during the first summer, a slight protection from the 

 intense heat and light of the sun. On old fields and pastures this is 

 afforded by short grasses and low scattered herbaceous vegetation, 

 like sweet fern and blueberry. A light cover of ferns or other small 

 herbs will often cast just enough shade to protect the pine seedling, 

 yet afford it sufficient sunlight with which to manufacture food. x On 

 the other hand, white-pine seedlings grow so slowly during the first 

 four or live years that they are very easily killed by tall, dense, vege- 

 tation of any kind, such as berry bushes, golden rod, fireweed, fern 

 brakes, or rank wild grasses. Not only does such vegetation keep 

 out needed light, but its roots take from the soil the moisture which 

 the young white pine requires. Under the protection of young, fast- 

 growing hardwood sprouts, witch hazel, dogwood, and similar under- 

 growth, white-pine seedlings may thrive for a year or two, but the 

 shade of such stands is usually too dense for continued growth of the 

 pine (see PI. Ill, fig. 2, and PI. IV, fig. 1 ) . In stands containing broad- 

 leaf trees many white-pine seedlings are smothered by fallen leaves. 



To determine the influence of different degrees of shade upon the 

 vitality and rate of growth of white-pine seedlings a number of sam- 

 ple plots were laid out in 1905 at Keene, N. H., in stands of different 

 crown density, but in other respects alike. Table 1, based on counts 

 in 10 plots of 1 square rod each, shows the average size and number 

 of seedlings per square rod in 1905 and the number and size of those 

 still alive in 1909. 



Table 1. — Vitality and rate of growth of seedlings under different degrees of shade. 



Crown cover. 



Average number of 



• seedlings per 



square rod. 



Per cent 

 living. 



Average height. 



Average 

 growth in 

 4 years of 

 seedlings 



. 



1905 



1909 



1909 



1905 



1909 



which 

 survived. 





271 

 102 

 100 



15 

 62 

 94 



5.5 

 60.8 

 94.0 



Inches. 

 1.5 

 1.5 

 1.5 



Inches. 

 4.5 

 10.0 

 11.0 



Inches. 



3.0 





8.5 





9.5 







GROWTH OF INDIVIDUAL TREES. 



An important characteristic of white pine is that its growth is 

 steady and uniform up to an advanced age. In this it differs from all 

 the other eastern and many of the western pines, in which the rate 



1 Influence of Shade and Other Factors on Plantations, by G. W. Kimball and E. E. Carter. Forestry 

 Quarterly, Vol. 11, No. 2, p. 176. 



673S°— Bull. 13—14 2 



