young tree; sapling
Refers to a tree that is still young and small, often in the context of planting, gardening, or forestry.
I planted a young tree in the garden.
この幼木はまだ実をつけない。
This young tree doesn't bear fruit yet.
Compound of 幼 (young, immature) and 木 (tree). The reading ようぼく follows the on'yomi of both characters.