Yǐ

Softness is what sets the second stem apart. 乙 (Yǐ) is yin wood, paired with 甲 and placed right after it. 三命通會 卷二 makes it wind in the sky and growing trees on the ground, 活木, living wood, whereas its 甲 is timber with the root already cut. 淵海子平 has the contrast too: its poem gives 甲 no branches or roots and says the roots of 乙 are planted deep.

The verse starts by overturning that softness. Sheep and ox stand for 未 and 丑, the yin earth branches, and the commentary says 乙 sitting on them can master that earth as a butcher handles an animal. One 丙 or 丁 is enough, it goes on, for 乙 to stand unafraid in the metal months of 申 and 酉, the Monkey and Rooster. The vine of the last line is 乙 leaning on 甲 or 寅, and with that support spring and autumn months are both acceptable.

A reader starts from the season and the water around this stem, since the commentary warns that in the 子 month with 辛, 壬 or 癸 showing, even a 午 gives little chance of growth. In the table used here 乙 has 長生, the stage of birth, at 午 and 死, the stage of ending, at 亥, counted backward from the yang pattern. That placement drew an objection in 滴天髓's own commentary, which asks why 乙 should die at 亥 when 亥 holds 壬, its true mother. To 乙, 壬 is a Direct Resource, so the stage table and the ten gods can pull in different directions at the same branch.