The 2026 World Cup kicks off in just a few weeks.
2026年世界杯再过几周就要开赛。
The grass on which the tournament's 104 matches will being played has a vital but often overlooked role.
承载本届赛事104场比赛的草皮发挥着至关重要却常被忽视的作用。
Scientists have fed, mowed and stamped on miles of turf to getting it right.
为了把草坪做到最佳状态，科学家们给数英里的草皮施肥、修剪，并在上面反复踩踏测试。
It happened just eight minutes into the match.
事情发生在比赛开始仅8分钟后。
Ángel Di María stole the balls from a Canadian defender and took off toward his opponent's goal.
安赫尔·迪马利亚从一名加拿大后卫脚下断球后，朝对方球门飞奔而去。
One of Argentina's greatest footballers of all times had only the keeper to beat in a decisive moment in the group stages of the 2024 Copa America football tournament.
在2024年美洲杯足球赛小组赛阶段的一个决定性时刻，阿根廷有史以来最伟大的足球运动员之一面前只剩下守门员需要攻破。
But as he dribbled the ball towards the goal, he seemed to struggle to control it.
但当他带球冲向球门时，他似乎很难控制住球。
Confronted by the Canadian goalkeeper at the edge of the penalty area, all Di Maria could muster was a relatively weak toe poke.
迪马利亚在禁区边缘面对加拿大队守门员时，所能做出的只是一次相对无力的脚尖捅射。
The keeper blocked it easily.
守门员轻松挡下了这个球。
After the match, the Argentinean coach and players offered an explanation for what might have gone wrong.
赛后，阿根廷队教练和球员就可能出现的问题给出了解释。
The reigning World Cup champions claimed the quality of the grass on the pitch in Atlanta, Georgia, in the US, affected their performance.
这支卫冕世界杯冠军球队称，美国佐治亚州亚特兰大球场上的草皮质量影响了他们的表现。
The stadium where the match was being played – normally home to NFL side the Atlanta Falcons and Major League Soccer teams Atlanta United – usually has an artificial pitch, but it had been replaced with a temporary grass surface just days before the tournament.
举办这场比赛的体育场通常是NFL球队亚特兰大猎鹰队和美国职业足球大联盟球队亚特兰大联队的主场，平时使用的是人造场地，但在赛事开始前几天刚被换成临时天然草皮。
Players complained that the ball jumped like "a springboard", describing the pitch as a "disaster".
球员们抱怨说，球像“跳板”一样弹起，并把球场形容为一场“灾难”。
Concerns about the quality of the pitches continued to dog the tournament as games were played in other stadiums around the US.
随着比赛在美国各地其他体育场进行，对球场质量的担忧继续困扰着这项赛事。
With the 2026 World Cup approaching, it is criticism that co-hosts US, Canada and Mexico will be eager to avoid.
随着2026年世界杯临近，联合主办国美国、加拿大和墨西哥都会急于避免这种批评。
And They've brought in a team of specialists to makes sure there are no complaints.
他们还请来了一支专家团队，以确保不会有人抱怨。
Over the past eight years researchers have bounced balls, stomped boots and abused patches of grass in the search for the perfect turf.
在过去八年里，研究人员为了寻找完美草皮，不断让球在草地上弹跳、用球鞋踩踏，并对一块块草坪进行高强度折腾。
They've fed, watered and nurtured different mixes of grass species to see how they'll cope.
他们给不同草种组合施肥、浇水并精心培育，以观察它们如何适应。
And they've measured blades of grass millimetre by millimetre to find their perfect length.
他们还逐毫米测量草叶，以找出最理想的长度。
"It's a lot of pressure," says John Sorochan, a professor at the University of Tennessee, who has been contracted by Fifa to helps oversee the growth, installation and care of the grass pitches at all 16 World Cup stadiums, including five that are covered by domes.
“压力很大，”田纳西大学教授约翰·索罗坎说。他受国际足联聘请，协助监督全部16座世界杯体育场草皮球场的培育、铺设和养护，其中包括5座有穹顶覆盖的场馆。
"Those are the ones that really have me worried," Sorochan says, "Because the Sun's gonna come up, but it's not going to come up inside.
“那些才是真正让我担心的球场，”索罗坎说，“因为太阳会升起，但它不会在室内升起。
Plants needed light, ideally sunlight, to growing."
植物需要光，理想情况下是阳光，才能生长。”
With the 2026 men's World Cup now just weeks away, the cumulative result of more than 170 different experiments conducted by Sorochan and his fellow researchers is about to be putting to the tested.
距离2026年男足世界杯如今只有几周时间，索罗昌和他的研究同事们开展的170多项不同实验所积累出的成果，即将接受检验。
They have built on decades of research on the science of cultivating and installing turfgrass on sports pitches.
他们以数十年来关于运动场草坪培育和铺设科学的研究为基础。
Yet the grass pitches they have developed for the different stadiums across the US, Canada and Mexico will be trampled by 21 players at a time for more than 90 minutes per game, across 104 matches.
然而，他们为美国、加拿大和墨西哥各地不同体育场开发的草坪球场，将在104场比赛中，每场被21名球员同时踩踏90多分钟。
The ambitions of the world's top football players and billions of fans around the world will rest on how the grass holds up.
世界顶级足球运动员的雄心，以及全球数十亿球迷的期待，都将取决于草坪能否经受住考验。
Just five millimetres can determine if a pitch plays like "velcro" or a pristine natural carpet that aids the quick passing of the ball needed for exciting play, Sorochan says.
索罗坎说，仅仅五毫米就能决定一块球场踢起来是像“魔术贴”一样滞涩，还是像一张完美的天然地毯，帮助实现精彩比赛所需的快速传球。
It took him and his colleagues hours of experimentation to determine the exact height at which each pitch should be mowed.
他和同事们花了数小时进行实验，才确定每块球场应修剪到的精确高度。
On miniature pitches at their research facilities in Knoxville, Tennessee, US, they shot footballs out of bright red machines, carefully observing and measuring their speed and bounce.
在美国田纳西州诺克斯维尔研究设施里的小型球场上，他们用鲜红色机器发射足球，并仔细观察和测量足球的速度与弹跳。
They wheeled a boxy, steel contraption across the grass so that a football boot attached to a post could pound the surface and test its springiness.
他们推着一个方盒状的钢制装置在草地上移动，让固定在立柱上的足球鞋反复撞击草面，以测试它的弹性。
The researchers tested the turf for not only how the ball interacts with the surface but also the traction it gives players.
研究人员测试了草坪，不仅看球与场地表面如何相互作用，也看它能给球员提供多大的抓地力。
They looked for ways to minimise divots during matches and avoiding wet spots that might interrupt the flow of a game.
他们寻找办法，尽量减少比赛中出现的草皮坑痕，并避免可能打断比赛节奏的湿滑区域。
Worst still, a poor surface could have catastrophic consequences – leading to career ending injuries for players worth millions.
更糟的是，糟糕的场地表面可能造成灾难性后果，导致身价数百万的球员遭受足以终结职业生涯的伤病。
The geographic spread of stadiums also means the pitches have to flourish in dramatically distinct climatic zones – from the humid heat of Mexico City and Miami to the cooler of Toronto and Boston.
体育场分布地域广泛，也意味着这些球场草坪必须能在截然不同的气候区中茁壮生长，从墨西哥城和迈阿密的湿热，到多伦多和波士顿的凉爽环境皆是如此。
To cope with this, the researchers have developed roots systems, irrigation methods and maintenance schedules that are specific to each location.
为了应对这一点，研究人员已经开发出适用于各个地点的根系、灌溉方法和养护计划。
They have also tested different grass species to find the ideal type for the conditions.
他们还测试了不同草种，以找出最适合这些条件的理想类型。
In warmer climates the turf will consist of Bermuda grass while cooler climates will have a mix of Kentucky bluegrass and perennial ryegrass.
在气候较温暖的地区，草坪将由百慕大草组成，而气候较凉爽的地区则会混用肯塔基早熟禾和多年生黑麦草。
Sorochan and his team determined that Bermuda grass pitches should be cutting slightly shorter, because they're denser and dry more quickly than pitches of Kentucky bluegrass and perennial ryegrass.
索罗钱和他的团队认定，百慕大草球场应修剪得略短一些，因为它们比肯塔基早熟禾和多年生黑麦草球场更密实，也干得更快。
To help make the pitches more uniform and durable, plastic fibres similar to those used in artificial turf, have been woven into the sod.
为了让球场草坪更加均匀耐用，类似于人造草坪中使用的塑料纤维已被编织进草皮中。
Still, footballers who play in Europe, where pitches are typically cool climate grasses, might be surprised walking onto a Bermuda grass pitch in Miami or Kansas City.
不过，在欧洲踢球的球员可能会感到意外，因为欧洲球场通常使用冷季型草，而他们在迈阿密或堪萨斯城走上的会是百慕大草球场。
" They'll look at this and say, 'This isn't what I've in Germany – this is more like a putting green,'" Sorochan says.
索罗钱说：“他们会看着这个说，‘这和我在德国用的场地不一样，这更像是高尔夫球的推杆果岭。’”
Each pitch will be slightly different, he admits.
他承认，每块球场都会略有不同。
But because of his research he believes the variation will be minimal.
但基于他的研究，他认为这种差异会很小。
"It's just the massive scale of temporary fields that are gonna be built at one time" that makes Trey Rogers III, a professor at Michigan State University (MSU), anxious.
让密歇根州立大学教授特雷·罗杰斯三世感到焦虑的，“只是这些临时球场要在同一时间大规模建成”。
He has been aiding Sorochan in preparation for the World Cup.
他一直在协助索罗坎为世界杯做准备。
The pitches must be perfect, almost miraculous.
这些球场必须完美，几乎要达到奇迹般的程度。
Fifa has put its faith in Sorochan and Rogers, celebrities in the obscure field of grass science.
国际足联把信任寄托在索罗坎和罗杰斯身上；他们是草坪科学这一冷门领域的知名人物。
The pair have never faced a challenge like the 2026 World Cup – and the stakes are high.
这两人从未面对过像2026年世界杯这样的挑战，而其中的利害关系十分重大。
But it isn't the first time they've laid down turf for football's biggest stage.
但这并不是他们第一次为足球界最大的舞台铺设草坪。
Rogers fell in love with grass working on a golf course in the American South.
罗杰斯在美国南部的一座高尔夫球场工作时爱上了草坪。
But his moved to football came in 1992 when Fifa was looking for help installing a grass pitch inside the Pontiac Silverdome in Michigan for four matches during the 1994 World Cup.
但他转向足球领域是在1992年，当时国际足联正在寻求帮助，要在密歇根州庞蒂亚克银顶体育场内铺设一块草坪，以供1994年世界杯期间的四场比赛使用。
The stadium was home to an NFL team, the Detroit Lions, who played on artificial turf.
这座体育场是NFL球队底特律雄狮队的主场，而他们平时在人造草皮上比赛。
Like many Americans, Rogers knew nothing about the biggest sporting event on the planet.
和许多美国人一样，罗杰斯对这个地球上最大的体育赛事一无所知。
"I uttered the famous words that nobody ever lets me forget," Rogers says.
罗杰斯说：“我说出了那句有名的话，大家到现在都不让我忘掉。”
"'What's the World Cup?'
“‘世界杯是什么？’
."
。”
Even so, Fifa selected Rogers to be in charge of growing and installing a grass pitch inside the stadium.
即便如此，国际足联还是选中了罗杰斯，让他负责在体育场内培育并铺设一块草皮球场。
After a series of experiments, his team at MSU decided to grow a mix of Kentucky bluegrass and perennial ryegrass in a sandy soil.
经过一系列实验后，他在密歇根州立大学的团队决定在沙质土壤中种植肯塔基早熟禾和多年生黑麦草的混合草种。
The sand would aid drainage while the two grass species could grow in a cool climate with relatively little direct sunlight.
沙子有助于排水，而这两种草能够在气候凉爽、直射阳光相对较少的环境中生长。
Rogers and his colleagues planted seed outside the dome in 1,994 hexagonal trays.
罗杰斯和同事们在穹顶外的1994个六边形托盘里播下了种子。
It took thousands of hours of labour, much of it done by hand.
这耗费了数千小时的劳动，其中许多工作都是手工完成的。
Sorochan was a student working on the project at the time.
索罗坎当时还是一名参与该项目的学生。
" I was literally the person that was tamping the sand," Sorochan says.
“我当时真就是那个在夯实沙子的人，”索罗坎说。
The hexagonal modules were one of the team's greatest innovations.
这些六边形模块是该团队最重要的创新之一。
The roots of the grass could be kept intact when the sections of turf were moved into the dome.
当一块块草皮被移入穹顶体育场时，草根可以保持完整。
It would be the first time a natural grass field was installed on top of an artificial pitch in a domed stadium.
这将是首次在有穹顶的体育场内，把天然草坪铺设在人工球场之上。
When Rogers watched a team enter the dome for their first practice, they didn't inspect the pitch.
当罗杰斯看到一支球队进入穹顶体育场进行第一次训练时，他们并没有检查球场。
Apparently, it felt normal to them.
显然，对他们来说感觉很正常。
Like little boys, they tried to punt footballs high enough to reach the roof of the gargantuan dome.
他们像小男孩一样，试着把足球踢得足够高，好碰到这座巨型穹顶的屋顶。
Rogers considered the project a success.
罗杰斯认为这个项目取得了成功。
It would earn him a nickname: the "guru of grass".
这会为他赢得一个绰号：“草坪大师”。
But at the end of the 1994 World Cup, Sorochan climbed to the top of the dome and looked down at the pitch.
但在 1994 年世界杯结束时，索罗坎爬到穹顶顶部，俯视着球场。
"You could see the wear on the field," Sorochan says.
“你可以看到球场上的磨损，”索罗坎说。
"I thought, wow, how do we make that better?"
“我当时想，哇，我们怎样才能把它做得更好？”
Sorochan spent the rest of his time as a graduate student researching how best to grow grass indoors.
索罗坎在研究生阶段余下的时间里，一直在研究如何最好地在室内种植草坪。
And when Fifa contacted Sorochan in 2018 for help with the 2026 World Cup, he asked Rogers and MSU to join him.
当国际足联在2018年联系索罗坎，请他为2026年世界杯提供帮助时，他邀请罗杰斯和密歇根州立大学加入进来。
What they'd have to pull off made their work at the Silverdome in 1994 seem like a child's science fair project.
他们必须完成的任务，让他们1994年在银穹体育馆的工作看起来像孩子的科学展项目一样简单。
Typically, sod is grown as locally as possible in soil similar to where it will be installed.
通常，草皮会尽可能在当地种植，并使用与最终铺设地点相似的土壤。
The act of cutting and moving the turf can stress the plants and they often need several weeks to recover.
切割和移动草皮的过程会给植物造成压力，它们通常需要几周时间才能恢复。
At the World Cup, however, many of the pitches will be installed just 10 days before their first match.
然而，在世界杯上，许多球场将在首场比赛前仅10天才完成铺设。
Joe Wilkins III's sprawling sod farms outside Denver, Colorado, US, is responsible for the World Cup pitches in Dallas, Atlanta, and Houston.
乔·威尔金斯三世位于美国科罗拉多州丹佛市郊的大型草皮农场，负责达拉斯、亚特兰大和休斯敦的世界杯球场草坪。
These three stadiums will host more than a quarter of the tournament between them.
这三座体育场合计将承办本届赛事四分之一以上的比赛。
The stadiums are all domes, where no direct sunlight reaches the pitch.
这些体育场都是穹顶场馆，没有直射阳光照到球场。
"They're the biggest challenges," Wilkins says, whose grandfather founded the Green Valley Turf Company in 1962.
“它们是最大的挑战，”威尔金斯说。他的祖父于1962年创办了绿谷草坪公司。
Bright green grass covers hundreds of acres at the company's farm.
在这家公司的农场里，鲜绿色的草覆盖着数百英亩的土地。
To prepare the sod, Wilkins' staff planted seed in sand on top of thin plastic.
为了培育草皮，威尔金斯的员工把种子种在薄塑料膜上方的沙土里。
This helps to protect the roots when it is harvested and reduce the shock the plants experience.
这有助于在收割草皮时保护根部，并减少植物受到的冲击。
Over the following weeks, workers water and mow the grass meticulously, adding fungicide, fertiliser, humates, sea kelp and silica.
在接下来的几周里，工人们细致地给草浇水、修剪，并添加杀菌剂、肥料、腐殖酸盐、海带和二氧化硅。
"The grass never takes a day off," Wilkins says.
“草从来不会休息一天，”威尔金斯说。
Sorochan has visited Green Valley Turf Company several times in the last few years, and Wilkins shipped sod to the University of Tennessee to help Sorochan's experiments.
过去几年里，索罗坎曾多次走访绿谷草坪公司，而威尔金斯也把草皮运到田纳西大学，以帮助索罗坎进行实验。
There, the team had built a state-of-the-art shade house to replicate conditions inside a domed stadium while MSU used a 2,100sq m (23,000sq ft) asphalt pad to replicate laying turf on stadium floors.
在那里，团队建造了一座最先进的遮阴棚，用来模拟穹顶体育场内部的条件；与此同时，密歇根州立大学则使用一块面积为2100平方米（23000平方英尺）的沥青场地，来模拟在体育场地面上铺设草皮。
To stabilise the turf at outdoor stadiums, a gravel base is laid below a firm layer of sand, which the sod is then rolled out onto.
为了稳固室外体育场的草坪，人们会在一层结实的沙层下面铺设砾石基础，然后把草皮在沙层上铺展开。
For the temporary pitches laid on top of artificial pitch surfaces in NFL domes, an interlocking plastic grid and woven plastic sheeting is used instead of the gravel base to provide adequate drainage.
对于铺设在NFL穹顶体育场人工场地表面之上的临时球场，人们使用互锁塑料网格和编织塑料布来替代碎石基层，以提供足够的排水能力。
Just weeks before the World Cup begins, Wilkins and his staff are now undertaking the laborious process of cutting and rolling up the grass.
距离世界杯开幕仅剩数周，威尔金斯和他的员工现在正进行切割并卷起草皮这项费力的工作。
Using what Wilkins describes as "giant pizza cutters" attached to farm vehicles, they slice the sod into 1.2m (4ft) strips.
他们使用威尔金斯所说的装在农用车辆上的“巨型披萨切刀”，把草皮切成1.2米（4英尺）宽的条状。
They wait until the Sun is setting so the grass is dry, then roll it up and load it onto refrigerated trucks.
他们等到太阳快落山、草已经干了的时候，再把草皮卷起来，装上冷藏卡车。
At the same time, dozens of other refrigerated trucks are hauling over a million square feet of grass from a handful of rural sod farms to stadiums across North America.
与此同时，几十辆其他冷藏卡车正把超过一百万平方英尺的草皮从少数几家乡村草皮农场运往北美各地的体育场。
" I've never done anything as big in my career," said Alan Ferguson, Fifa's senior pitch management manager.
国际足联高级球场管理经理艾伦·弗格森说：“我职业生涯中从未做过规模这么大的事情。”
At those domed stadiums, when the grass finally arrives, it may be the last time it's touched by sunlight, but it still has to thrive for weeks more.
在那些有穹顶的体育场里，当草坪最终运抵时，那可能是它最后一次接触阳光，但它还必须继续旺盛生长数周。
After the sod is unrolled at the covered stadiums, a magenta glow will blanket the entire pitch, emanating from dozens of white, metal bars just a few metres above the grass.
在有顶棚的体育场铺开草皮后，一片洋红色的光芒将覆盖整个球场，这些光来自草面上方仅几米处数十根白色金属灯条。
These retractable LED grow lights can be moved into position to provide the grass with the energy it needs to grow.
这些可伸缩的LED植物生长灯可以移动到合适位置，为草坪提供生长所需的能量。
In Dallas, at the home of the Cowboys NFL team, for example, the grow lights descend from the roof.
例如，在达拉斯的NFL球队牛仔队主场，植物生长灯会从屋顶降下。
"You can be working underneath them and mowing and doing all you need to be doing, and the grass is just growing," Sorochan says.
“你可以在它们下面工作、修剪草坪，做所有该做的事，而草也会照常生长，”索罗坎说。
Growing grass without direct sunlight is much easier today than it was at the Silverdome in 1994 because of advances in light emitting diode (LED) technology.
由于发光二极管（LED）技术的进步，如今在没有直射阳光的情况下种草，比1994年在西尔弗多姆体育场时要容易得多。
Sorochan isn't worried about a repeat of what happened at the Copa America.
索罗坎并不担心美洲杯上发生的情况会重演。
At the Mercedes-Benz Stadium in Atlanta, where Argentina and Canada faced each other, the distance between the grass pitch and the artificial turf used for American football games underneath was too shallow, creating the kind of trampoline effect the players reported, he says.
他说，在亚特兰大的梅赛德斯-奔驰体育场，阿根廷队和加拿大队曾在那里交锋，天然草坪球场与下方用于美式橄榄球比赛的人造草皮之间的间距太浅，从而产生了球员们所说的那种蹦床效应。
Fifa has asked for more of a buffer in 2026.
国际足联要求在2026年留出更大的缓冲余地。
• The mathematics of the perfect penalty shootout
• 完美点球大战背后的数学
• We still don't know why curling stones move the way they do
• 我们仍然不知道冰壶石为什么会以那样的方式移动。
• Why world records seem to be getting harder to beat - according to maths
• 从数学角度看，为什么世界纪录似乎越来越难打破。
The 2025 Club World Cup also provided a partial rehearsal.
2025年世俱杯也提供了一次局部预演。
The turf researchers deployed many of the same materials, techniques and workers used this year.
草坪研究人员采用了许多与今年相同的材料、技术和工作人员。
"The Club World Cup was a tournament in its own right," said Fifa's Ferguson.
“俱乐部世界杯本身就是一项独立赛事，”国际足联的弗格森说。
"But it also naturally offered us the opportunity to test and try some of these logistics."
“但它也自然而然地给了我们测试和尝试其中一些后勤安排的机会。”
While there were a few complaints still about quality of the pitches at the club tournament from players and coaches, Fifa insisted they met international testing standards.
尽管在那项俱乐部赛事中，球员和教练仍对球场质量有一些抱怨，但国际足联坚称这些球场符合国际检测标准。
Fifa has spent more than $5m (£3.7m) on grass research for the 2026 World Cup, according to Ferguson.
据弗格森称，国际足联已为2026年世界杯的草坪研究投入超过500万美元（370万英镑）。
It's a lot of money for something that few people even think about when watching the drama of football's most prestigious competition.
对于这样一种在人们观看这项足球最高级别赛事的戏剧性场面时几乎很少会想到的东西来说，这是一大笔钱。
Rogers hopes that in the long run, the research he and Sorochan have done will lead to wider improvements in how grass is used in sport at many levels.
罗杰斯希望，从长远来看，他和索罗坎所做的研究能推动各级体育运动中草皮使用方式得到更广泛的改进。
It may even persuade some American football teams to switch from artificial turf, even in domed stadiums, he says.
他说，这甚至可能说服一些美式橄榄球队从人造草皮改用天然草皮，即使是在有穹顶的体育场里也是如此。
"There will be techniques and things that they're developing that you could even take to the local high school," adds Elizabeth Guertal, a professor of turfgrass management at Auburn University who isn't involved in the World Cup project.
“他们正在开发的一些技术和做法，甚至可以带到当地高中去使用，”奥本大学草坪草管理教授伊丽莎白·盖塔尔补充说，她并未参与这个世界杯项目。
Meanwhile, Rogers and Sorochan know well-tended grass, like a child, is tender and resilient.
与此同时，罗杰斯和索罗坎知道，精心养护的草就像孩子一样，既娇嫩又有韧性。
It can brace a striker as they make a sharp cut with a ball and cushion a goalkeeper at the end of a sparkling save.
它能在前锋带球急转时提供支撑，也能在门将完成一次精彩扑救后起到缓冲作用。
They have created the stage for the drama to unfold.
他们已经搭建好了这场大戏展开的舞台。
Now it's up to the players to see whose dreams will come true.
现在，就要看球员们谁能梦想成真了。
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