Pinus strobus

Pinus strobus L. – Eastern White Pine

group: 	SOFTWOODS

Macroscopic structure of wood

heartwood/sapwood: 	heartwood

description: 	wide sapwood, yellowish white (very often blue stain); heartwood is yellowish (when first cut), later it has tendency to change colour to light reddish brown (indistinct difference between these zones)

rings: 	slightly distinct boundary between rings, wide rings; very gradual transition from early wood to late wood in ring

resin canals: 	very numerous, visible in X, R and T

rays: 	invisible

texture: 	slightly flatsawn (T) and radial figure (R); little decorative wood

Microscopic structure of wood

brief overview: RC; ray HetC, low; windowlike pitting, ray tracheid cell wall smooth

ring: 	very gradual transition from early wood to late wood tracheids in ring	X

bordered pits on tracheids: 	one in a row	R

tracheid thickenings: 	absent	R, T

resin canals: 	very large, predominantly solitary, very numerous	P, T

epithelial cells: 	thin-walled epithelial cell, big (4–6)	X, T

rays: 	heterocellular	R

width of rays	uniseriate and fusiform	T, (X)

height of rays: 	low to medium high, 5–15	T

cross field pitting: 	windowlike (1–2)	R

ray tracheid: 	one or more rows along the upper and lower margins and in the middle of the ray, smooth-walled ray tracheid	R axial parenchyma: 	absent	X, (R, T)

other: 	thin-walled tracheids

Wood properties

density: 	light

ρ 0: 	390 kg/m3

ρ 12-15: 	415 kg/m3

ρ green: 	700 kg/m3

shrinkage: 	medium

- volumetric (βV): 	9,3 %

- radial (βR): 	2,7 %

- tangential (βT): 	6,3 %

mechanical properties: 	not strong

ultimate strength in compression ||: 	34 MPa

ultimate strength in bending: 	61 MPa

ultimate strength in tension ||: 	76 MPa

hardness: 	soft

Janka's hardness: 	23 MPa

technological properties: 	no problem with drying, working, finishing (resin makes problem with finishing), sapwood is more permeable to preservatives than is heartwood

resistance: 	heartwood rated as moderate resistant to decay, sapwood rated as slightly or non-resistant to decay

Wood utilization

in Europe small amount of wood; timber, windows, doors, matches, wood wool, fuel wood etc.

References