Anatomy of a Bowl — Bias Explained
A lawn bowl is not a perfect sphere. It is deliberately manufactured with an asymmetric shape — one side is slightly flatter than the other — which causes the bowl to curve as it slows down. This built-in curve is called the bias.
The bias side of the bowl is marked with a small disc or circle. When you deliver a bowl, the bias side always curves toward the ground — meaning the bowl will always curve toward the side you place facing down at delivery.
A bowl curves because of its asymmetric shape — the bias side curves inward as the bowl slows
Bias is measured on a scale. Narrow bias bowls curve less and travel on a straighter path — better for slower greens or beginners who want more predictability. Wide bias bowls curve significantly — preferred by experienced players and on faster greens where the bowl has more time to curve.
On slower greens, narrow bias bowls are often easier to control because the bowl doesn't travel far enough for a wide bias to fully develop. On faster greens, the extra time of travel means wider bias bowls are very common at competition level.
The bias is tested and stamped by World Bowls to ensure it meets a minimum standard. You'll see a World Bowls stamp or sticker on approved bowls. Always check for this when purchasing second-hand bowls.
Choosing the Right Size & Weight
Bowls come in sizes from 00 (smallest) to 6 (largest), though most adult players use sizes 2 to 5. The right size is one you can comfortably hold without straining — your middle finger should just reach around the running surface with your thumb resting naturally on top.
Weight matters too. Heavier bowls hold their line better on windy days and carry momentum well on slow greens. Lighter bowls are easier to control for players with less upper body strength, especially on fast greens where less effort is needed.
Most clubs have a set of "trial" bowls in various sizes. Spend time with several before buying. A good club coach will help you identify the right size — don't rush this decision, as it will affect your game for years.
Understanding the Green & Rink Markings
The playing surface in lawn bowls is called the green — a large, flat, finely maintained area of grass (or carpet indoors). The green is divided into sections called rinks, and each game is played within the boundaries of a single rink.
| Feature | Description |
|---|---|
| Green | The entire playing area, typically 31–40 metres square |
| Rink | A lane within the green, approximately 4.3–5.8 metres wide |
| Centre line | The line down the middle of the rink where the mat is placed |
| Boundary pegs/strings | Mark the edges of the rink; bowls outside are dead |
| Dead ball line | The line at each end beyond which the jack is dead |
| T-line | A line at each end marking the minimum jack position |
Multiple rinks run parallel across the green, allowing several games to be played simultaneously. You are only allowed to bowl within the marked boundaries of your rink — any bowl that travels outside the rink boundary, or past the far end, is considered dead and is removed from play.
"The green is not just turf — it is a living surface that changes by hour and season, demanding respect and attentiveness from every player."
The Jack, the Mat, and the Ditch
Three key pieces of equipment define the shape of every end: the mat, the jack, and the ditch.
A toucher is a bowl that physically touched the jack during its delivery. Touchers are marked with chalk and remain live even if they end up in the ditch. This is one of the most important rules to remember, as a toucher in the ditch can still count as the shot bowl.