If your birth year carries a 戊 (Wù) heavenly stem, the stems of all twelve months are locked in from the start. This is the bazi month stem table for wu year charts, built by the Five Tigers rule (五虎遁 wǔhǔdùn): a 戊 year opens its first month on 甲 (Jiǎ), and each month after advances a single stem. The full year runs below.
The 12 month pillars for a Wu 戊 year
Every month begins at a major solar term (節 jié), not on a calendar date. Find your birth branch and read across.
| Month | Branch | Starts at (solar term) | Month pillar |
|---|---|---|---|
| 1st | Tiger 寅 Yín | Li Chun 立春 (~4 Feb) | 甲寅 Jiǎ Yín |
| 2nd | Rabbit 卯 Mǎo | Jing Zhe 惊蛰 (~6 Mar) | 乙卯 Yǐ Mǎo |
| 3rd | Dragon 辰 Chén | Qing Ming 清明 (~5 Apr) | 丙辰 Bǐng Chén |
| 4th | Snake 巳 Sì | Li Xia 立夏 (~5 May) | 丁巳 Dīng Sì |
| 5th | Horse 午 Wǔ | Mang Zhong 芒种 (~6 Jun) | 戊午 Wù Wǔ |
| 6th | Goat 未 Wèi | Xiao Shu 小暑 (~7 Jul) | 己未 Jǐ Wèi |
| 7th | Monkey 申 Shēn | Li Qiu 立秋 (~7 Aug) | 庚申 Gēng Shēn |
| 8th | Rooster 酉 Yǒu | Bai Lu 白露 (~7 Sep) | 辛酉 Xīn Yǒu |
| 9th | Dog 戌 Xū | Han Lu 寒露 (~8 Oct) | 壬戌 Rén Xū |
| 10th | Pig 亥 Hài | Li Dong 立冬 (~7 Nov) | 癸亥 Guǐ Hài |
| 11th | Rat 子 Zǐ | Da Xue 大雪 (~7 Dec) | 甲子 Jiǎ Zǐ |
| 12th | Ox 丑 Chǒu | Xiao Han 小寒 (~5 Jan) | 乙丑 Yǐ Chǒu |
A 戊 year opens on 甲 wood and reaches its own stem 戊 in the fifth month, the Horse. That 戊午, earth on the peak of summer fire, is the hallmark of the Wù column.
A worked example
Take a birth in the Horse month (午 Wǔ) of a 戊 year. The fifth row gives 戊午 (Wù Wǔ) — the year stem repeating on the month, earth over full-summer fire, one of the most concentrated fire-earth pillars in the whole cycle. The Horse month opens at Mang Zhong (芒种 mángzhòng) around 6 June, so a birth on 4 June of that year has not yet entered the Horse and still sits in the Snake month, giving 丁巳 (Dīng Sì). A day or two on the calendar rewrites the pillar, which is why the solar term decides the row, not the date. What that blazing branch then does to each Day Master is laid out on the Horse month page.
Which years read from this column
Calendar years ending in 8 carry the 戊 stem: 1988, 1998, 2008, 2018. The Li Chun boundary is not academic here — Li Chun 1988 fell on 4 February at 22:42, which means a morning birth on 4 February 1988 was still inside the previous 丁卯 year and reads from the Ding-year column, while a birth an hour before midnight had crossed into the 戊 year and belongs here. The same logic sends every January birth of a calendar 戊 year back to the previous table.
The arithmetic behind the rows
Written out, the Five Tigers rule is: first-month (寅) stem index = (year-stem-index mod 5) × 2 + 2; each later month adds 1, mod 10. Year stems pair: 甲/己, 乙/庚, 丙/辛, 丁/壬, 戊/癸 share columns. With 甲 numbered 0, a 戊 year has index 4: (4 mod 5) × 2 + 2 = 10, and 10 mod 10 = 0, which is 甲 — hence the 甲寅 opening. Eleven single steps later the column closes on 乙丑. The same arithmetic gives 癸 (index 9) the identical result, which is why the two stems share this page’s layout.
What the month pillar governs
The month pillar carries the month palace, read first for career climate and for the parental line. Its deeper importance is structural: the month branch holds the season’s ruling element, and the season sets the baseline temperature of the entire chart. That is why the month branch counts for so much when we weigh a strong or weak Day Master — a Day Master born in its own season starts already supported. In a 戊 year the month stems begin on wood and climb through fire and earth, which governs how strongly the season backs the Day Master.
Concretely, the branch’s season — spring 寅卯辰, summer 巳午未, autumn 申酉戌, winter 亥子丑 — hands every Day Master one of the five states (旺相休囚死 wàng xiàng xiū qiú sǐ). A Wu Earth Day Master born under this year’s 戊午 signature month sits in summer, where Fire feeds Earth at the Supported grade; that comfortable position and its risks are worked through in Wu Earth born in summer. The same chart recast into the 甲寅 Tiger month would open the year under Wood’s pressure instead.
Reading it in context
Read the month stem as the first step, not the conclusion; it works alongside the branch’s hidden stems and the surrounding pillars. Because the Five Tigers rule pairs 戊 with 癸 (Guǐ), the month table for Gui 癸 years is identical to this one and makes a clean cross-check. For all five columns together see the master month stem table, and for what the Tiger month itself hides, the stems and branches alphabet sets out the hidden stems.
Wu-year month stem FAQ
Is the 甲子 Rat month in this table special?
It is the first pillar of the entire sixty-cycle, and in a 戊 year it lands on the eleventh month. Nothing mystical follows from that, but it makes the row easy to remember and a quick way to verify you are reading the right column.
My 1988 birthday is 4 February. Which year am I?
It depends on the hour. Li Chun 1988 arrived at 22:42 that night, so births earlier in the day still belong to the 1987 丁卯 year; only a birth after 22:42 opens this 戊 table. This is the textbook case for checking the exact term time rather than the date.
Why does 戊 share a column with 癸?
The formula reduces the year-stem index mod 5, and 戊 (4) and 癸 (9) reduce to the same remainder. All five pairings — 甲/己, 乙/庚, 丙/辛, 丁/壬, 戊/癸 — fall out of that one step.
Confirm your own Wu-year month pillar against the exact solar-term boundary — plot your full chart free with the Butcher Boy calculator and match it to the table above.