Wood and Metal Compatibility in Korean Saju

Wood and metal compatibility in Korean saju depends on which wood and which metal. Wildflower 乙 and Sword 庚 are a classic combination. Big Tree 甲 + Sword 庚 and Wildflower 乙 + Jewel 辛 clash, and in Big Tree 甲 + Jewel 辛, metal shapes wood.

What are the wood and metal saju types?

Your saju type is the top character of your day pillar, one of ten, and it describes your core self; saju experts call it your Day Master. Saju is the Korean system of reading personality and timing from your birth year, month, day and hour, also known as the Four Pillars or BaZi, and our introduction is what saju is.

Two of the ten types are wood and two are metal:

• Big Tree 甲 (yang wood): upright, principled, a natural leader
• Wildflower 乙 (yin wood): adaptable, social, quietly persistent
• Sword 庚 (yang metal): decisive, blunt, built for action
• Jewel 辛 (yin metal): precise, refined, high standards

Yang is the outward, direct side of an element, and yin is the inward, flexible side. More on the ten types in our guide to what a Day Master is and on the saju type overview.

Your type comes from the day you were born in a 60-day cycle, so you need an exact birth date to find it. You can get yours free, with no sign-up, on the saju type page.

Does metal control wood in saju?

Yes. In the five-element control cycle, metal controls wood, the way an axe cuts a tree or shears trim a hedge. The control cycle is the order in which each element keeps another in check: wood controls earth, earth controls water, water controls fire, fire controls metal, and metal controls wood.

In saju, "control" is not the same as "harm". It means shaping:

• If you are wood, metal is the element of rules, responsibility and pressure. It is what makes you take yourself seriously, and it can also wear you down.
• If you are metal, wood is the element you control, which saju reads as what you pursue and manage: money, results and, traditionally, the partner you chase.

Saju also cares whether the two types share the same polarity. When a yang controls a yang, or a yin controls a yin, the control is read as harsher and more direct. When yang and yin meet, the control is read as more orderly, like a rule you agree with. That pattern runs through all four pairs below.

How does wood and metal compatibility compare across the four pairs?

Two of the four pairs clash, one is a classic combination, and one follows the plain rule of metal shaping wood. The table sums them up.

A clash is a pair of heavenly stems that push against each other, and a combination is a pair that pulls toward each other. In Korean, a clash is called chung (충) and a combination is called hap (합).

What happens when Big Tree 甲 meets Sword 庚?

Big Tree and Sword are a clash, the textbook case of metal controlling wood at full force. Both are yang, so neither backs down. The tree wants to stand where it is; the sword wants to cut a clear path.

What it looks like in real life:

• Respect at first sight, because each sees how strong the other is.
• Arguments that are direct and blunt, often about who decides.
• The tree partner can feel judged; the sword partner can feel the tree is being stubborn on purpose.

What helps: clear roles. This pair does better when each person owns separate decisions. A clash also brings movement, so this pair often gets a lot done together once it stops competing.

Why are Wildflower 乙 and Sword 庚 a natural pair?

Wildflower and Sword form one of the five classic stem combinations (乙庚). The other four are 甲己, 丙辛, 丁壬 and 戊癸. In a combination, two characters are drawn to each other, and the pair is said to transform into a third element; 乙庚 transforms into metal.

What it looks like:

• The sword brings direction and decisiveness. The wildflower brings warmth and tact.
• The wildflower softens the sword's edges; the sword gives the wildflower something firm to grow around.
• Korean readers often point to a combination like this as a sign of strong romantic pull.

The one thing to watch: because the pull is strong, the wildflower partner can bend too far to keep the peace. It works best when they still say no out loud sometimes.

What happens when Wildflower 乙 meets Jewel 辛?

Wildflower and Jewel are a clash (乙辛). Both are yin, so this clash is quieter than Big Tree and Sword, and it shows up as small, precise criticism rather than big fights. The jewel notices every flaw; the wildflower takes each comment to heart and pulls back.

What helps: the jewel partner saying what they like as clearly as what they would change, and the wildflower partner raising hurt feelings early instead of letting them pile up.

What happens when Big Tree 甲 meets Jewel 辛?

There is no clash or combination between Big Tree and Jewel. The relationship follows the basic rule, metal controlling wood, in its orderly yang-and-yin form.

The image is fine metal shaping a tree: pruning shears or a carving knife, not an axe. The jewel trims, and the tree grows in better shape.

What it looks like: a calm, structured pair. The jewel gives feedback and standards; the tree gives stability and protection. It goes wrong only if the trimming never stops and the tree partner starts to feel managed.

Can one day of difference turn a combination into a clash?

Yes. Here is a worked example with three made-up birthdays, calculated with fixed saju rules.

A day pillar is the pair of characters for your birth day: a heavenly stem on top, which is your saju type, and an earthly branch below.

• Joon and Sora: 乙 and 庚 combine. This is the natural pair.
• Joon and Hana: 乙 and 辛 clash. Hana was born just one day after Sora, yet her match with Joon reads very differently at the level of saju type.

The branches add another layer. Joon and Hana both have 卯 as their day branch, so they share the same "ground", which tends to make daily habits feel familiar even when the types clash. This is why a stem match is the headline, not the whole story.

Is the saju type match the whole story?

No. Your saju type is one character out of eight. A full compatibility reading also looks at the other seven characters in both charts, how your branches interact, and which ten-year luck cycle each of you is in right now.

A clashing pair can have charts that balance each other well once everything else is counted. The same is true of the other element pairs, as our guide to water and fire compatibility shows.

In Korea, checking a couple's compatibility from both saju charts has a name, gunghap (궁합), and it has long been part of how families think about marriage. A gunghap reading compares both full charts, not just the two types.

How can you check your own wood and metal match?

Enter both birthdays on the compatibility page to see your compatibility score for free. We calculate both charts with fixed saju rules, adjusted to the real sun time in each birth city, and then explain them in plain English. The full reading is paid, and with Read us together you can invite your partner into one room to read it side by side.

Are wood and metal a bad match in saju?

No. Metal controlling wood means shaping, not harm. One of the four wood and metal pairs, Wildflower 乙 and Sword 庚, is a classic combination, and every pair can work when both full charts are read together.

Which metal type is best for a Big Tree?

Jewel 辛 is usually the smoother match, because yang wood and yin metal meet in the orderly form of control. Sword 庚 clashes with Big Tree, but that also brings energy and drive.

Which wood type is best for a Sword?

Wildflower 乙 combines with Sword 庚, so it is the classic choice. Big Tree 甲 clashes with Sword, which can mean more friction but also a pair that rarely gets bored.