GLOSSARY. 389 



Transit. A surveyor's instrument for measuring angles, etc. 

 Transpiration. The process by which water is taken up by the 



roots of plants and given off to the air through the leaves 



and branches. 

 Tree. A perennial woody plant with a single stem which from 



natural tendencies generally divides into two or more 



branches at some distance from the ground. 

 Tree-crown. That part of a tree that is branched, forming a 



head. 

 Tree-digger. Ordinarily a plow-like implement having a sharp 



knife-like blade that is drawn through the soil by a team 



and cuts the roots off the trees at a distance from the base 



of the tree-trunk. Where large quantities of trees are to 



be dug this is a most important implement. There are 



various kinds; one style cuts on both sides of the row at 



one time. 



Tri. Prefix meaning three. 



Triangulation. The method of survey by dividing into triangles. 

 Tripod. A three-legged support for an instrument. 

 Turgid. Distended; applied to leaves and other parts when 



filled w r ith water. 

 Umbel. An umbrella-like form of inflorescence, (e. g. flower 



clusters of Caraway. Parsnip.) 

 Unisexual. Bearing either male or female organs, not both. (e. 



g. flowers of Willows.) 



Variety. A distinct and valuable variation from the original. 

 Valve. One of the parts of a dehiscent pod. 

 Valvate. Opening by valves. 

 Volume. Amount or mass of a tree or log. 

 Water capital. The entire water of the earth. 

 Weed. A plant out of place, a generally troublesome plant, not 



of any appreciable economic value. 

 Whorl. Applied to leaves when arranged in a circle around the 



stem. 



Wings of a leaf. The expanded portion; the blade. 

 Windbreak. A single row or belt of trees, which serves as a 



protection from wind. 



Wood. The hardened tissue of a stem. A forest. 

 Working plan. A pre-arrangement of the method of growing 



and harvesting a forest crop of a particular tfact. 



