Softwood anatomy

Longitudinal tracheids

Earlywood and Latewood

Latewood Earlywood

EW-LW transition - abrupt

Latewood

Earlywood

EW-LW transition - gradual

Latewood

Earlywood

EW-LW transition - intermediate

Latewood

Earlywood

EW-LW transition - abrupt

Latewood

Latewood

Latewood

Earlywood

Earlywood

Earlywood

EW-LW transition - gradual

Latewood

Latewood

Earlywood

Earlywood

EW-LW transition - intermediate

Latewood

Latewood

Earlywood

Earlywood

EW-LW transition - abrupt

Earlywood

Latewood

EW-LW transition - gradual

Latewood

Earlywood

Growth ring width variation

Three very different growth rates(Douglas-fir all shown at the same magnification)

Bordered pits

Inter-tracheid bordered pit

Bordered pits

Bordered pits – less common arrangements

Paired Alternate

Longitudinal parenchyma

Longitudinal parenchyma

Resin canals

Resin canals

Large diameter

Small diameter

Resin canals

Non-resinous Small resin canals Large resin canals

Resin canals

21

White pine Lodgepole pine

Spruce Douglas-fir

Resin canals

Non-resinous Small resin canals Large resin canals

Resin canals

Paired

Multiple

Traumatic

Rays – uniseriate rays

Uniseriate rays

Rays – fusiform rays

Fusiform ray(including horizontal resin canal)

Rays – fusiform rays

Fusiform ray(including horizontal resin canal)

Spiral thickening

Spiral thickening on inside of cell wall

Spiral thickening

Spiral thickenings

Cross-field pitting

Cross-field pitting

Lodgepole pine White spruce

Red pine Douglas-fir

Cross-field details

semi-bordered pits

bordered pitsbetween raytracheids

bordered pitsbetween raytracheids andlongitudinaltracheids

raytracheiddentations

Hardwoods

Red alder – aggregate rays

Red alder – aggregate rays

Genuine mahogany Red lauan

Red lauan – gum ducts