Wood is the element of growth. In Korean and wider East Asian thought the five elements (오행 ohaeng) are better read as five phases of change than as five substances, and wood is the phase when things push up and out: shoots in March, a new idea, the first year of anything.
Wood belongs to spring and to the east, where the sun rises. Its color in the Korean five color scheme (오방색 obangsaek) is 청 cheong, the blue-green of new leaves and deep water, one word that covers both. Of the classical virtues it is linked with 인 仁, benevolence.
In the cycles, water feeds wood, the way rain feeds a tree, and wood feeds fire, the way timber feeds a hearth. Wood breaks up earth with its roots, and metal cuts wood. Two stems carry wood, Gap 甲 and Eul 乙, and two branches, the Tiger 寅 and the Rabbit 卯.
A lot of wood
A chart heavy in wood is often read as full of drive and plans, someone always growing something. The tradition's note of caution is about direction: a forest with no clearing can get tangled, so some metal to prune it and fire to use it are read as helpful.
Little or no wood
A chart with little or no wood is common and does not mean anything is missing from your life. The tradition reads it as a chart where growth comes through other channels, and it simply means wood years, wood luck pillars and wood people can feel like a fresh breeze.
In Korean life
Wood's blue-green is one of the five colors in 색동 saekdong, the rainbow striped sleeves of children's hanbok, and in the five color garnish (오색 고명) on dishes such as japchae and tteokguk. Korean given names are sometimes chosen with an element in mind, and characters with the wood radical 木 are a classic choice when a family wants to add wood.