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STEM MORPHOLOGY

bud - an underdeveloped and unelongated stem composed of a short axis with compressed internodes, a meristematic apex, and primordial leaves and/or flowers. 
 

terminal bud - a bud at the tip of a stem responsible for terminal growth. 
 

axillary bud or lateral bud - buds along side the axis of a stem; they at were produced by the terminal bud during growth; once they grow out and form a lateral stem they become terminal buds of the lateral branch. 
 

flower bud - a bud containing a floral meristem which develops into flowers; usually larger than vegetative buds. 
 

leaf scar - a scar marking the former point of attachment of a leaf or petiole to the stem. 
 

internode - the part of the stem between nodes 
 

node - part of stem marking the point of attachment of leaves, flowers, fruits, buds and other stems. 
 

lenticel - rough areas on stems (and some fruits, ex. apple) composed of loosely packed cells extending from the cortex through the ruptured epidermis; serve as "breathing pores" for gas exchange. Only occur on young stems. 
 

growth rings - bud scale scars from the last terminal bud; they denote flushes of growth (usually per year). Can be used to age stems because usually 1 set of growth rings is produced per year on temperate trees in the Temperate Climatic Zone.