The 2026 World Cup kicks off in just a few weeks.
2026年世界杯再过短短几周就将开幕。
The grass on which the tournament's 104 matches will being played has a vital but often overlooked role.
本届赛事104场比赛将在其上进行的草皮，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.
为了把草坪做到合适的状态，科学家们给绵延数英里的草皮施肥、修剪，并在上面反复踩踏。
It happened just eight minutes into the match.
这件事发生在比赛开始仅八分钟后。
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抢断得球，然后冲向对方球门。
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的一个决定性时刻，阿根廷史上最伟大的足球运动员之一面前只剩下门将需要攻破。
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.
面对站在禁区边缘的加拿大门将，迪马利亚所能勉强做出的只是一次相对无力的脚尖捅射。
The keeper blocked it easily.
守门员轻松挡出了这脚球。
After the match, the Argentinean coach and players offered an explanation for what might have gone wrong.
赛后，阿根廷教练和球员对可能出错的原因给出了解释。
The reigning World Cup champions claimed the quality of the grass on the pitch in Atlanta, Georgia, in the US, affected their performance.
这支世界杯卫冕冠军声称，美国佐治亚州亚特兰大球场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.
这场比赛所在的体育场通常是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，平时使用的是人造球场，但就在赛事开始前几天，它被换成了临时天然草皮。
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，人们对球场质量的担忧仍持续困扰着这项赛事。
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，这正是共同主办国美国、加拿大和墨西哥急于避免的批评。
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，以确保不会有人提出抱怨。
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，为了寻找完美草皮，研究人员反复让球弹跳、用球靴踩踏，并对一块块草地进行高强度折腾测试。
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，以观察它们将如何适应。
And they've measured blades of grass millimetre by millimetre to find their perfect length.
他们还一毫米一毫米地测量草叶，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·索罗钱说。他受国际足联聘请，协助监督全部16座世界杯体育场草皮的培育、铺设和养护，其中包括5座带穹顶覆盖的场馆。
"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，“因为太阳会升起来，但它不会照进室内。
Plants needed light, ideally sunlight, to growing."
植物需要光，最好是阳光，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.
随着2026年男子世界杯如今只剩几周就要开赛，索罗坎和他的研究伙伴开展的170多项不同实验所累积出的成果，即将接受检验。
They have built on decades of research on the science of cultivating and installing turfgrass on sports pitches.
他们是在数十年来关于运动场草坪草培育和铺设科学的研究基础上继续推进的。
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天然草球场，将在104场比赛中，每场比赛被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，都将取决于这片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5毫米就能决定一块球场踢起来是像“魔术贴”一样粘滞，还是像一张纯净的天然地毯，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做实验，才确定每块球场应该修剪到的精确高度。
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内的小型球场上，他们用鲜红色机器发射足球，仔细观察并测量足球的速度和反弹情况。
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.
他们推着一个方方正正的钢制装置穿过草地，让固定在柱子上的足球鞋反复击打草面，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.
研究人员测试草坪时，不仅考察球与表面的相互作用，还考察草坪能为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.
他们寻找方法，尽量减少比赛中被踢起的草皮坑，并避免可能打断比赛流畅性的积水湿斑。
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皮必须在截然不同的气候区都能茁壮生长，从墨西哥城和迈阿密湿热的环境，到多伦多和波士顿凉爽的气候。
To cope with this, the researchers have developed roots systems, irrigation methods and maintenance schedules that are specific to each location.
为应对这一点，研究人员开发了适合每个地点的根系系统、灌溉方法和维护计划。
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.
在较温暖的气候条件下，草坪将由百慕大草组成；而在较凉爽的气候条件下，则会采用肯塔基早熟禾和多年生黑麦草的混合草种。
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.
索罗坎和他的团队确定，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致密，干得也更快。
To help make the pitches more uniform and durable, plastic fibres similar to those used in artificial turf, have been woven into the sod.
为了让球场更加均匀耐用，类似于人造草坪所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，因为那里的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将是百慕大草球场。
" They'll look at this and say, 'This isn't what I've in Germany – this is more like a putting green,'" Sorochan says.
索罗坎说：“他们会看着这块场地说，‘这不是我在德国用的那种场地，这更像是高尔夫球的果岭。’”
Each pitch will be slightly different, he admits.
他承认，每块球场的草坪都会略有不同。
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，正是“将一次性建造临时球场的巨大规模”。
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.
这些球场草皮必须完美，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，他们是在草坪科学这一冷门领域里的名人。
The pair have never faced a challenge like the 2026 World Cup – and the stakes are high.
这两人从未面临过像2026年世界杯这样的挑战，而且其中利害关系重大。
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盛大的舞台铺设草皮。
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.
但他转向足球是在1992年，当时国际足联正在寻找协助，要在密歇根州庞蒂亚克银穹体育场内铺设一块天然草球场，用于1994年世界杯期间的四场比赛。
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，他们在人工草坪上比赛。
Like many Americans, Rogers knew nothing about the biggest sporting event on the planet.
和许多美国人一样，罗杰斯对这项全球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：“我说出了那句出了名、谁都不让我忘掉的话。”
"'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天然草球场。
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，他在密歇根州立大学的团队决定在沙质土壤中混合种植肯塔基早熟禾和多年生黑麦草。
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，而这两种草则能在气候凉爽、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.
罗杰斯和他的同事们在穹顶外的1994个六边形托盘里播下种子。
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圆顶体育场时，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.
这将是首次在穹顶体育场的人造球场上方安装天然草坪。
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首次训练时，他们并没有检查球场草坪。
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，试着把足球高高踢起，直到足以碰到那座巨大穹顶的屋顶。
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".
这让他赢得了一个绰号：“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.
索罗昌说：“你能看到球场上的磨损。”
"I thought, wow, how do we make that better?"
“我当时想，哇，我们怎样才能把这件事做得更好？”
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，一直研究如何最好地在室内种草。
And when Fifa contacted Sorochan in 2018 for help with the 2026 World Cup, he asked Rogers and MSU to join him.
2018年，当国际足联联系索罗坎，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他的团队。
What they'd have to pull off made their work at the Silverdome in 1994 seem like a child's science fair project.
他们接下来必须完成的任务，让他们1994年在银顶体育场做的工作相比之下像是小孩的科学展项目。
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.
切割和搬运草皮的过程会给植物造成压力，它们往往需要数周时间才能恢复。
At the World Cup, however, many of the pitches will be installed just 10 days before their first match.
然而在世界杯期间，许多球场的草坪将在首场比赛前仅10天才铺设完成。
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，负责为达拉斯、亚特兰大和休斯敦的世界杯球场供应草坪。
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.
这些体育场全都是穹顶建筑，没有直射阳光能照到球场草坪。
"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年创立了绿谷草坪公司。
Bright green grass covers hundreds of acres at the company's farm.
在这家公司的农场里，鲜绿色的草坪覆盖了数百英亩土地。
To prepare the sod, Wilkins' staff planted seed in sand on top of thin plastic.
为了准备草皮，威尔金斯的工作人员在薄塑料层上方的沙子里播下种子。
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，并减轻植物所承受的冲击。
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，工人们会细致地浇水、修剪草坪，并添加杀菌剂、肥料、腐殖酸盐、海藻和二氧化硅。
"The grass never takes a day off," Wilkins says.
“草一天也不会休息，”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，索罗坎多次造访绿谷草坪公司，而威尔金斯也把草皮运到田纳西大学，帮助索罗坎开展实验。
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屋，用来模拟穹顶体育场内的环境；与此同时，密歇根州立大学使用一块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.
为了稳定露天体育场的草坪，人们会在一层坚实的沙层下面铺设碎石基层，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 穹顶球场人工场地表面之上的临时球场，会使用互锁塑料格栅和编织塑料膜来代替碎石基层，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.
距离世界杯开幕只有几周，威尔金斯和他的员工现在正进行切割并卷起草皮这一费力的工序。
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安装在农用车辆上的“巨型披萨切刀”，把草皮切成1.2米（4英尺）宽的条带。
They wait until the Sun is setting so the grass is dry, then roll it up and load it onto refrigerated trucks.
他们会等到太阳快落山、草已经变干时，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，另外几十辆冷藏卡车正把一百多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.
国际足联高级球场草坪管理经理艾伦·弗格森说：“在我的职业生涯中，我从没做过这么大的项目。”
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.
在那些穹顶球场里，当草坪终于运抵时，那也许就是它最后一次接触阳光，但它仍必须再旺盛生长数周。
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.
草皮在有顶棚的体育场铺展开后，几十根位于草地上方仅几米处的白色金属灯条会散发出品红色光芒，笼罩整片球场。
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 生长灯可以移动到位，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.
例如在达拉斯的牛仔队NFL主场，植物生长灯会从屋顶降下来。
"You can be working underneath them and mowing and doing all you need to be doing, and the grass is just growing," Sorochan says.
索罗坎说：“你可以在它们下面工作、修剪草坪，做所有需要做的事，而草就照样生长。”
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年在银顶体育馆时容易得多。
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事情会重演。
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，也就是阿根廷队与加拿大队交手的地方，天然草球场与下方用于美式橄榄球比赛的人造草坪之间距离太浅，造成了球员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年留出更大的缓冲空间。
• 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被打破
The 2025 Club World Cup also provided a partial rehearsal.
2025年世俱杯也提供了一次部分演练。
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今年使用过的相同材料、技术和工人。
"The Club World Cup was a tournament in its own right," said Fifa's Ferguson.
国际足联的弗格森说：“俱乐部世界杯本身就是一项独立赛事。”
"But it also naturally offered us the opportunity to test and try some of these logistics."
“但这自然也给了我们机会，去测试并试行其中一些后勤安排。”
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测试标准。
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.
对于一件很少有人在观看足球界最负盛名赛事的精彩场面时会想到的东西来说，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个层级体育运动中草坪使用方式的更广泛改进。
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工草坪改用天然草皮，即便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·格尔塔尔补充说，她并未参与世界杯项目。
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，精心照料的草就像孩子一样，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落地时起到缓冲作用。
They have created the stage for the drama to unfold.
他们已经搭好了舞台，让这场大戏得以展开。
Now it's up to the players to see whose dreams will come true.
现在，就看球员们谁能让梦想成真了。
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