Pores varying in size from rather large to minute, the largest being in the early wood.
Pores in early wood plugged with tyloses, collected in a few rows.
Pores in early wood in a rather narrow band, round, variable in size, densely filled with tyloses.
Change from early wood to late wood is gradual and the difference in density is not great.
Pores in early wood moderately large, not abundant, nearly round, filled with tyloses.
Pores in early wood in a broad band, oval in shape, mostly free from tyloses.
Pores in early wood in a rather broad band (occasionally narrow), oval in shape, see Fig. 148, tyloses present.
Pores in early wood not large and mostly in a single row, Fig. 150 (several rows in slippery elm), round, tyloses present.
The part of the wood in a growth ring of a tree that is produced earlier in the growing season. The cells of early wood are larger and have thinner walls than those produced later in the growing season. Compare late wood.