The part of the tree that is created wood products.
xylem
Sapwood = living xylem.
Heartwood = dead, structural xylem.
What is the thin layer of living cells just outside the sapwood (xylem) that generates new wood cells and gives wood its grain?
Cambium
it produces new xylem (wood) and a smaller number of ray cells, creating the growth rings and wood grain.
Dead tree cells that no longer serve any purpose except to support the tree.
Heartwood
What cells, produced by the cambium, extend out from the pith perpendicular to the tree’s axis, and in hollow form store plant sugars?
Ray cells
they radiate outward from the pith and serve in storage and lateral transport.
Which layer covers the cambium, transfers food and nutrients from the leaves to the rest of the tree, and forms part of the protective bark?
Phloem (inner bark)
It conducts sugars from the leaves and protects the cambium.
When the cambium grows rapidly at the beginning of each growing season, what kind of wood does it create within the xylem?
Earlywood (springwood)
light-colored, less dense wood formed in the spring.
As the climate warms later in the growing season, the cambium slows down and produces darker wood that is denser and harder than earlywood. What is this called?
Latewood (summerwood)
darker, denser growth formed later in the season.
What is the most common method of sawing lumber, and why is it used?
Plain-sawing is the most common method because it produces the highest quantity of usable lumber. Plain-sawn boards show flat grain on their faces and quarter grain on the edges.
What is live-sawn lumber, and what are its characteristics?
Live sawing (also called through-and-through sawing) cuts straight across the log without turning it. It produces very wide boards that show a mixture of grain patterns (flat, quarter, and rift grain).
What is quarter-sawn lumber, and what are its advantages?
cut with growth rings at about 60–90 degrees to the board face, giving vertical grain. It is more stable, resists warping, and shows decorative patterns, but yields less lumber and is more costly than plain-sawn.
What are the dimension of a standard board foot?
12”x12”x1”
What is the generic name for the type of tree that softwoods typically come from?