CONIFER NEEDLE INTERNAL MORPHOLOGY

1. Shape
   square  
   oval-rectangular  
   sectoroid  
   
2. Size
3. Internal Anatomy
   • Epidermis
   • Stomata, Guard Cells
     • position
     • sunken or not
     
   • Hypodermis, mono- bi-form
   • Mesophyll (parenchyma)
     • cell shape
     • wall form, elongate, crenulate
     • spongy (spaces)
   • Resin Ducts
     • Size
     • Position, external, internal, medial
     • # cells lining
     • wall thickness of lining cells
       
   • Vascular Cylinder (Stele)
     • Xylem
     • Phloem
     
   • Endodermis (Bundle Sheath)
     • thickness of wall
     • evenness of thickening
     • continuous, discontinuous
   • Transfusion Tissue
     • +/- thickened cells
     • shape of thickened cells
   • Vascular Bundle
     • Xylem, Phloem
         (in drawings, orient Xylem UP, adaxial)
     • Divided or Not
       spruce - how many dividing cells
       pine - haploxylon, diploxylon

TYPES TO DRAW

CUPRESSACEAE Thuja plicata
PINACEAE Tsuga caroliniana
PINACEAE Picea
PINACEAE Pinus one-needle
PINACEAE Pinus five-needle

Picea engelmanni vs. P. pungens




Pinus edulis vs. P. contorta