During the excavation, several general observations were made. In spite of the 

 large number of rootlets measured, very few growing tips were found, a condition 

 common on plants in soils having little surface moisture (Kramer 1949). The sinker 

 roots, together with some laterals, disappeared into crevices in the diorite or hardpan 

 and could not be traced to their ends. Most, but not all, main laterals developed inde- 

 pendently and avoided their neighbors (fig. 1). Eight instances of what appeared to be 

 true intraspecific grafting and one interspecific (with aspen) were noted as well as 

 several instances of self- grafting- -phenomena that have been recorded for other spe- 

 cies (Bormann and Graham 1959). The taproot was excavated to a depth of 35 inches; 

 the diorite prevented further digging. Sinker roots sometimes grow deeper than tap- 

 roots (Busgen and Munch 1929), but no comparisons could be made in this study. 



A light surface fire had burned through the stand 5 years previous to the excava- 

 tion, and apparently had killed some of the root ends. However, the dying of roots and 

 their parts from various causes is apparently a common occurrence (Busgen and Munch 

 1929). 



A striking feature of the exposure of the main laterals was the competition pro- 

 vided by the dense network of herbaceous and woody ground cover in the top 18 inches 

 of soil (fig. 2). In fact, this competition, judged by the number of rootlets tallied, and 



Figure 2. main lateral 45 feet from the main trunk and 10 inches 

 beneath the soil surface lies just below this root mass. This root 

 has few secondary laterals and little taper, giving the "ropelike" 

 appearance described by other investigators. 



