46 PHARMACEUTICAL BOTANY 
DESCRIPTION OF THE WHITE PINE TREE (MATURE 
SPOROPHYTE) 
From an underground spreading root system there arises an erect 
aerial trunk or stem that extends from the ground to the apex of the 
tree, ending in a terminal bud. The trunk rarely exceeds 3 feet in 
diameter and 125 feet in height and is averagely 1 }/% to 3 feet in 
Pig. 20. —Transverse section of white pine needle (leaf) showing epidermis (a), 
infolded parenchyma cells of mesophyll (&, &'), oil reservoir (t), endodermis (d), 
clear cellular area (e) surrounding fibrovascular tissue in center (/). X400. 
diameter and 50 to 90 feet high. At a varying distance above the 
soil, depending upon environal conditions as well as the age of plant, 
whorls of lateral branches (three to seven in a whorl) are seen ema¬ 
nating from the trunk in horizontal fashion at various levels up to 
near the apex. These become, under conditions prevalent when the 
tree is grown in the open, gradually shorter until the summit is 
