this fossil oak (genus Quercus) from Oregon one
can see the large vessels making up the earlywood and the
smaller diameter vessels arranged in flamelike patches making
up the latewood. Wide, multiseriate rays cut across the growth
rings. Very fine uniseriate rays can be seen in the wood
between the more visible thicker rays. Vessels in angiosperms
range in size from 50 to 300 micrometers in diameter depending
upon the species.