Hidden Stems 藏干
Cáng Gān · The stems concealed inside each branch — one, two or three per branch.
What it means
Each Earthly Branch conceals one to three Heavenly Stems. The main hidden stem matches the branch's own element; the middle and residual stems are leftovers from the season before and hints of the frame the branch belongs to. Yin, the Tiger branch, hides Jia, Bing and Wu — Wood, Fire and Earth together — while Mao, the Rabbit, hides only Yi.
Why it matters
Hidden stems are where most of the real content of a chart sits. Two charts can look similar on the surface and differ completely once the branches are opened, and a practitioner weighing which element is strongest counts hidden stems as well as visible ones. They also explain why some branches behave like mixtures: a branch holding three stems can act in three directions depending on what else is present.
| Branch | Main 本气 | Middle 中气 | Residual 余气 |
|---|---|---|---|
| 子 (Zi) | 癸 | — | — |
| 丑 (Chou) | 己 | 癸 | 辛 |
| 寅 (Yin) | 甲 | 丙 | 戊 |
| 卯 (Mao) | 乙 | — | — |
| 辰 (Chen) | 戊 | 乙 | 癸 |
| 巳 (Si) | 丙 | 庚 | 戊 |
| 午 (Wu) | 丁 | 己 | — |
| 未 (Wei) | 己 | 丁 | 乙 |
| 申 (Shen) | 庚 | 壬 | 戊 |
| 酉 (You) | 辛 | — | — |
| 戌 (Xu) | 戊 | 辛 | 丁 |
| 亥 (Hai) | 壬 | 甲 | — |
Where this site uses it
The chart tool exposes the hidden stems of each branch alongside the visible pillar, so the weighing is visible instead of happening off-screen.