Go Board Wood Grain Explained: Masame, Itame, Tenmasa, Tenchimasa and Shihomasa

When you look at Japanese go boards (goban) online, two boards of the same wood and the same thickness can be listed at very different prices. Much of that gap is the grain: which part of the log the board was cut from, and in which direction.

Japanese board listings describe this with a handful of words: masame, itame, tenmasa, tenchimasa, shihomasa, kiura, kiomote. Once you know them, a listing tells you far more, and you will know which photograph to ask for before you decide.

The short version

• Grain is decided by kidori (木取り): where in the log the board is cut, and at what angle to the growth rings.
• Masame (柾目, straight grain) is generally ranked above itame (板目, flat grain) and is rarer.
• Tenmasa, tenchimasa and shihomasa are kinds of masame, named by how the grain runs on the end grain (the front and back sides of the board) and the other faces.
• You cannot tell them apart from a photo of the playing surface. Ask for photos of the ends and sides.
• Itame boards are divided into kiura and kiomote; kiura is ranked higher.
• Rankings differ between makers. Treat any hierarchy as “commonly said”, not as a fixed rule.

Grain comes from how the log is cut

A board’s grain depends on where and how it was sawn from the log.

• Cut so the growth rings meet the playing surface at close to a right angle, and you get masame: straight, parallel stripes across the surface.
• Cut along the rings (tangentially), and you get itame: arching, flame-like patterns.

Masame boards are taken from the radius of the log, avoiding the core and the pale sapwood, so one log yields only a limited amount. That scarcity is what links grain to rank and price. Board makers say a masame board needs a large, old tree; one Japanese maker (Maruhachi) puts it at a tree of at least 400 years.

Grain matters most in hon-kaya (本榧, genuine Japanese torreya), where kidori moves the price a great deal. The difference between hon-kaya and the substitute woods is covered in Honkaya vs Shinkaya.

Masame: straight grain

On a masame board the growth rings stand close to upright against the surface, so the top shows straight, parallel lines. It has a calm, even look, and it has traditionally been ranked highest for go and shogi boards.

There is a practical side as well. Masame is generally said to warp and move less than itame as the wood shrinks and swells, so the board stays flat more easily over the years. For gifts and commemorative boards, where rank matters, masame is the usual choice.

Itame: flat grain

Itame shows arching, wave-like or flame-like patterns. More itame can be cut from a single log, so these boards are usually more affordable.

Itame ranks below masame, but it has a bold, characterful figure, and some enthusiasts prefer it. For anyone who wants a real wooden board within a budget, an itame board is perfectly serviceable.

Kiura and kiomote

Itame boards are further divided by which side of the plank faces up:

For go boards, kiura is ranked above kiomote, and kiomote is the lowest grade in the usual hierarchy. If a listing says kiura, that is a point in its favour among itame boards, not a defect.

Tenmasa and tenchimasa

Look at a masame board from the front or back side (the koguchi, 木口, the end grain) and you see the growth rings rising toward the playing surface. How far those lines run straight gives the name:

Tenmasa is a cut that puts the emphasis on the beauty of the playing surface. With tenchimasa both the top and the underside are masame, so the more beautiful face can be chosen as the playing surface, while the left and right sides show flat grain.

Both put straight grain on the playing surface, so a photo of the top alone cannot tell you which you are looking at. You need to see the end grain.

Shihomasa: straight grain on all four faces

Shihomasa (四方柾) means masame on all four long faces: the top, the underside, and the left and right sides. Getting complete straight grain on four faces requires a very large log, so these boards are extremely rare and are often treated as the top grade, with prices to match.

Note that oimasa (追柾), a cut between masame and itame in which flat grain appears on one side of the playing surface, is often mistaken for shihomasa: one Japanese board maker (Maruhachi) says that most boards described as shihomasa are in fact oimasa taken for shihomasa. For an expensive board, check photos of both ends and both sides.

How the grades are usually ranked

A commonly cited ranking is:

shihomasa > tenchimasa > tenmasa > oimasa > itame (kiura > kiomote)

This is a general guide, and makers do not all agree. One Japanese maker places tenmasa at the very top as “the finest cut for the beauty of the surface”, while another lists shihomasa, tenchimasa, tenmasa in that sequence. Real value also depends on thickness, origin, and the wood’s colour, lustre and knots, not grain alone.

• Grade first: shihomasa, tenchimasa, tenmasa
• Balance: a clean, straight masame
• Budget, or for the figure: itame (kiura)

How thickness affects value is covered in Go & Shogi Board Thickness.

What to look at in photos

When choosing from photographs, check:

1. The playing surface: do the stripes run straight (masame) or arch (itame)?
2. The end grain (koguchi): do the lines run straight only near the top (tenmasa) or all the way to the underside (tenchimasa)?
3. The left and right sides: straight grain here as well suggests shihomasa.
4. Colour consistency, knots and resin pockets.

Lighting changes how grain looks, so ask for several photos. If you are buying from outside Japan, it is entirely reasonable to ask the dealer for photos of the ends and sides before you pay. A dealer who knows boards will understand why you ask.

FAQ

Is masame always better than itame? In rank and resistance to warping, masame is generally placed higher. Itame has its own appeal, and the right choice depends on budget, taste and use.

What is the difference between tenmasa and shihomasa? Tenmasa is masame whose end grain runs straight only on the upper side. Shihomasa has masame on the top, underside, and both left and right sides. Shihomasa is generally the rarest and most expensive.

Does grain affect how the board plays? Masame is said to warp less. Storage conditions (dryness, humidity, direct sun) usually matter more, so where you keep the board is just as important.

Can I judge grain from photos alone? To a fair extent, if you have photos of the surface, ends and sides. For a high-priced board, see it in person if you can, or ask a specialist dealer to explain the kidori.

Related pages

• How to Choose a Go Board: Wood, Form and Thickness
• Honkaya vs Shinkaya
• Go & Shogi Board Thickness
• Where to Buy Go Equipment Outside Japan

This page summarises general terminology for go board grain, based on explanations from the Nihon Ki-in and Japanese board makers (checked October 2026). Grading and terminology differ between makers; for a particular board, confirm the kidori with a specialist dealer. Kayajudo is an independent guide to Japanese go and shogi equipment, and we can also order boards, stones and pieces from makers and shops in Japan for you and ship them abroad — see Ordering from overseas.