你想知道的关于风滚草的一切

你想知道的关于风滚草的一切

Like cowboys, wagon trains and buffalo, tumbleweeds are icons of the Old West. These twisted balls of dead foliage rolling across deserts and the open range are staples of Western movies and the American imagination.

像牛仔、马车队和水牛一样，风滚草是旧西部的象征。这些扭曲的死树叶滚过沙漠和开阔的牧场是西方电影和美国人想象的主要内容。

Love them or hate them, tumbleweeds have been a regular fixture in the American West for more than 100 years. (Photo: Jez Arnold [CC BY-SA 2.0]/Flickr)

But the truth about tumbleweeds isn’t so simple. They may be romantic symbols of our national love affair with the Wild West, but tumbleweeds are also invasive weeds called Russian thistle, and many modern-day Westerners fear they’re taking over.

但关于风滚草的真相并非如此简单。风滚草可能是我们国家与蛮荒的西部之间爱情的浪漫象征，但它也是一种被称为俄罗斯蓟的入侵性杂草，许多现代西方人担心它们正在接管。

How they got here

他们是如何来到这里的

In 1873, Russian immigrants arrived in South Dakota carrying flax seed that was apparently contaminated with Russian thistle seeds (Salsola tragus). Once sown, these invaders from another continent quickly sprouted, unhampered by natural predators and diseases to keep them in check. Each winter after Russian thistle plants die, the brittle bushy parts snap off at the roots and blow away, dispersing seeds wherever they tumble (about 250,000 per plant).

1873年，俄罗斯移民携带亚麻种子抵达南达科他州，亚麻种子显然被俄罗斯蓟种子污染了。一旦播种，这些来自另一个大陆的入侵者就会迅速发芽，不受自然捕食者和疾病的限制。每年冬天，俄罗斯蓟植物死后，脆弱而浓密的部分从根部折断，被风吹走，种子四处散落(大约每株25万颗)。

Because Russian thistle thrives on little precipitation and easily exploits disturbed land stripped of native species, it was able to quickly take hold in the vast agricultural fields and overgrazed rangelands of the arid West. By the end of the 1800s, this intruder had already rolled its way across most western states and into Canada, carried by wind and even railroad cars.

由于俄罗斯蓟生长茂盛，降水量少，而且很容易利用被破坏的土地，破坏的土地上没有本土物种，所以它能够很快在广阔的农田和干旱的西部牧场上扎根。到19世纪末，这个入侵者已经通过风，甚至火车车厢，穿越了大部分西部州，进入了加拿大。

A government botanist sent to investigate in the early 1890s could barely believe his eyes: "One almost continuous area of about 35,000 square miles has become more or less covered with the Russian thistle in the comparatively brief period of twenty years."

一位在19世纪90年代初被派去调查的政府植物学家几乎不敢相信自己的眼睛:“在相对较短的20年里，一个大约35000平方英里的几乎连续不断的地区或多或少地被俄罗斯蓟覆盖了。”

Life of a tumbleweed

风滚草的生命

Tumbleweeds can grow several feet high. (Photo: miheco [CC BY-SA 2.0]/Flickr)

When we think of tumbleweeds we rarely picture fledgling Russian thistle bushes, which many consider beautiful with their reddish purple striped stems, tender leaves and delicate flowers. Growing from six inches to three feet tall (with some sprouting to Volkswagen Beetle size), they later develop sharp spines.

当我们想到风滚草时，我们很少会想到初生的俄罗斯蓟灌木，许多人认为它们是美丽的，有着红紫色条纹的茎、嫩叶和娇嫩的花朵。它们从6英寸长到3英尺高(有些还长出了像大众甲壳虫那么大的刺，后来就长出了锋利的刺。

Many animal species feed on the succulent new shoots, including mule deer, pronghorn, prairie dogs and birds. Russian thistle hay actually saved cattle from starvation during the Dust Bowl of the 1930s when other feed wasn’t available.

许多动物物种以多汁的新芽为食，包括骡鹿、叉角羚、土拨鼠和鸟类。在20世纪30年代的沙尘暴期间，俄罗斯的蓟草实际上拯救了饥饿的牛，当时没有其他饲料。

Russian thistle is beautiful in bloom before it dries up and tumbles away. (Photo: miheco [CC BY-SA 2.0]/Flickr)

But there’s a down side. Tumbleweeds have never stopped spreading. Nearly every state in the U.S. is now home to Russian thistle, as well as several newer tumbleweed species that arrived as immigrants from around the world.

但也有不利的一面。杂草从未停止蔓延。现在，美国几乎每个州都有俄罗斯蓟，以及一些来自世界各地的新移民种的风滚草。

The ongoing drought out West has been a particular boon for these ubiquitous raiders, launching a recent explosion of prickly spheres rolling across mesas and through canyons and towns, and even creating a new giant hybrid species that’s currently sweeping across California.

对于这些无处不在的袭击者来说，西部持续的干旱是一个特别的福音，最近引发了一场爆炸，多刺的球体在梅萨斯地区、峡谷和城镇、甚至克里亚地区滚动。这是一种新的巨型杂交物种，目前正在席卷加利福尼亚。