Is climate change threatening the iconic cricket bat?

Climate plays a big role in cricket, but not in the way you might think.

While warming weather patterns put player health in the crosshairs, and may change the nature of pitch preparation, a crucial element of one of the world's most popular sports could also be at risk.

The bat.

Cricket's iconic hitting instrument hasn't changed much since the game's inception: the bat has almost always been a rectangular block of wood, ‘bowed’ into its iconic shape, and wedged with a cane or timber grip.

This is despite Australia's penchant for innovation: from Dennis Lillee's aluminium blade (banned), Ricky Ponting's graphite-reinforced willow (banned) and Gray-Nicolls’ carbon fibre infused handle (banned).

Those Aussie experiments tested the rules and led to a rigid definition of the bat being brought into effect: a blade must be made entirely of wood.

Typically, bats are made from so-called English or Kashmir Willow (in truth a timber from subspecies the white willow Salix alba).

There is very little difference between the English and Kashmir variations. Genetically, they are the same species, but grown in different regions. That place-of-growth results in the English variant being slightly less dense than the subcontinental version, a shade whiter in colour, and a softer ‘ping’ when struck by a ball (some players will also note the Anglo name often carries a higher price point).

Kookaburra Sport's bat maker Lachlan Dinger explains despite being the same species subtle differences between willow grown in different parts of the world has effectively narrowed the supply chain to these two regions. The UK has the best conditions, Kashmir is in the world's biggest bat market. But the mass scale of harvest and production on the subcontinent lends itself to higher grade bats.

"Probably, the average punter might not even be able to tell the difference, but certainly, if you’ve looked at enough bits of willow, be that English, Kashmir, Canadian, Serbian, wherever it's grown, you can tell the difference between them," Dinger tells Cosmos.

"On volume, it's harder to make Kashmir willow bats at the same quality level. I’m sure there’ll be the odd ‘unicorn cleft’ where it's really low density, really light, looks really nice, but they’re few and far between."

From the harvesting of the timber, a willow cleft – the rectangular timber block which is eventually carved into the blade – is selected by a bat maker.

Formula One teams spend millions of dollars making lighter, more aerodynamic parts; sleeker swimsuits are developed for professional freestylers and sneakers are constantly made lighter (and more expensive) for elite runners, but cricket bats have all-but reached peak performance.

Incremental improvement is likely to always happen, but as Gray-Nicolls’ master bat maker Stuart Kranzbuhler tells Cosmos, the shape of the bat has all-but-hit peak perfection.

When developing the (now outlawed) carbon fibre handle with RMIT scientists, Gray-Nicolls – one of the world's most famous bat makers – wanted to see if engineers at the university could unlock something bat crafters had missed.

"At the end of the day, what they actually developed, what they said would be the perfect shape cricket bat for optimal use, was exactly the bat we’d already designed, which was the Predator, which Andrew Symonds was using," Kranzbuhler says.

"We were pretty happy with that, we knew we were on the right track."

Despite synthetic materials and metals being trialled (and banned) in cricket, sustainability is something that bat makers like Kranzbuhler consider vital for the game's future.

New solutions, therefore, might be necessary.

English willow grows best in cool climes, usually taking 15 years to reach full maturity before harvesting.

And the southern regions of the United Kingdom are the goldilocks zone for willow – cold, but not too cold for premium Salix. The trees grow in summer, harden in winter and deliver a grain density perfect for smacking sixes.

Kranzbuhler describes English willow as a "hard grain in a soft wood". By further compressing that soft wood, bat makers imbue the lightweight bat with an even more powerful profile.

The best English willow provides elite players with a weapon that is light and impact resistant. When struck by a leather ball, the wood's air-filled cells are instantly deformed, but spring back as if the bowler's best efforts didn't exist at all.

The chemistry of the cricket ball

"There's no other timber, really, with those properties: that you could compress to the weights that we do in a way that would withstand the impact of a five-and-a-half-ounce ball at 140 kilometres an hour."

But as continually increasing human carbon emissions cause the world's climates to change, these prime growth conditions may be compromised.

Seven years ago, major floods in Kashmir put paid to supplies of Kashmir willow. Such events are expected to worsen as average temperatures increase.

And now, Britain's warming winters are, quite literally, going against the grain.

"One-hundred percent, climate change is affecting it," Kranzbuhler says.

Increases to temperatures in Britain's south will speed the growth rate of the tree during those hardening winter months. That risks shifting what is generally considered the superior English-origin willow towards a grain profile of the Kashmir-grown product.

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That worries bat makers who want to offer the best possible product for their brands at every level of the game.

"Trees are growing faster, and then they’re a little bit sporadic as well… you mightn't get a cold year, and so you’re getting inconsistent grain growth, then you might get a freezing cold year where a tree might actually stop growing," Kranzbuhler says.

"The old growth trees aren't there any more, everything is renewed growth… inferior trees are coming through, you still get some very nice ones, but for the majority, it isn't what it used to be."

It's not just changing climate impacting the traditional growth of willow trees.

Cane, too, is in shorter supply, and that's the primary material in the bat handle.

And as more and more bats are sold, that means more willow trees need to be grown and felled.

As Dinger observes, players are potentially buying multiple bats in the time it takes a single tree to mature.

Combined with the influence of climate, he's starting to see a drop in the quality of willow available to build bats.

"If someone buys a bat every two years, they’re effectively buying seven bats in the time it takes for the tree to grow," Dinger says.

"Grading is done on a cosmetic basis, but we’re starting to see more wide-grain timber, which is traditionally not as sought after. Your closer, slower rate-of-growth that gives you that closer grain is becoming less common.

"As a result, we’re seeing a difference in what we have to accept as a grade one, two or three [cleft] from the willow merchant."

That has bat makers considering ways to make their products more sustainable.

To do that, however, rule makers might need to consider updating the laws of cricket to allow viable, cost-effective alternatives to traditional materials – whether a composite product like Gray-Nicolls’ outlawed carbon-fibre handle, a 3D printed product which mimics the properties of cane handles, or a new blade material altogether.

While any timber could be used for a bat, willow is, for now, unmatched among the trees.

But other plant fibres could offer a sustainable alternative to wood. One option is bamboo.

Developed by Cambridge University engineers and brought to life by boutique bat maker Garrard & Flack, the laminated bamboo bat offers a cheap, easily grown material to manufacturers.

And while Gray-Nicolls and RMIT found the shape of the blade might be close-to-perfection, the research conducted by Cambridge found bamboo offers one particular benefit.

"What we really found is that the bamboo outperforms the willow on so many levels," Ben Tinkler-Davies tells Cosmos. He led the research that brought the bamboo bat to life.

That's partly thanks to a larger ‘sweet spot’ – the region of the blade which transfers the most power to the ball while also leading to minimal vibration throughout the bat – emerging as a unique characteristic of the Cambridge product.

This performance enhancement means bamboo bats could be made smaller to emulate the weight profile of traditional willow.

But the big benefit is in the sustainability profile of using laminated bamboo.

While merchants need more trees to meet the demand of manufacturers, Tinkler-Davies says the industry also suffers from a waste problem. Over a quarter of willow clefts are discarded due to natural defects.

That's good for firewood, but bad for an industry which can't afford to spare what willow it has.

Unfortunately, the current stipulation by the law makers that blades be wholly wooden might again be tested by this product.

That's because despite its brown, rigid characteristic, bamboo is a member of the true grass family Poaceae.

Could a grass blade turn the game on its head in the name of sustainability? Tinkler-Davies hopes so.

"We’ve gone from having one prototype back then… to a few different iterations and we’re currently looking for industry partners to work with and hit the ground running," he says.

"But I think the bigger question, the bigger movement, is talking with the MCC [the Marylebone Cricket Club at Lords] and trying to engage the biggest stakeholders in cricket who are willing to really push the boat out and try something new."

Cosmos contacted the MCC for comment on the Laws of the Game but is yet to receive a response.

Originally published by Cosmos as Is climate change threatening the iconic cricket bat?

Matthew Agius is a science writer for Cosmos Magazine.

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