Java Edition:

Name Default value Allowed values [hide]Description
axisy xThe log or stem is oriented east–west.
yThe log or stem is oriented vertically.
zThe log or stem is oriented north–south.

Bedrock Edition:

NameMetadata Bits Default value Allowed valuesValues for
Metadata Bits
[hide]Description
pillar_axisNot Supportedy xUnsupportedThe log or stem is oriented east–west.
yUnsupportedThe log or stem is oriented vertically.
zUnsupportedThe log or stem is oriented north–south.