白太 is read as しらた (shirata) and means sapwood.
しらた
shirata
たいはく
Venus (planet)
たいはくせい
たいはくざとう
refined sugar
しらが
white hair
はくまい
polished rice
はくば
unrefined sake
はくねつ
becoming excited
はくじょう
confession
しらゆき
white snow
しらゆり
white lily
しらゆりじょしだいがく
Shirayuri Women's College
しろにんじん
parsnip (Pastinaca sativa)