Several plant species that grow in arid, steppe-like environments use the wind to propagate. The structure that is pushed by the wind is usually called tumbleweed. This structure will detatch from its root or stem and will roll on the ground. In most such species, the tumbleweed consists of the whole plant apart from the root system. Sometimes, only a hollow fruit or inflorescence detaches. Tumbleweed species occur most commonly in steppe and arid ecosystems, where frequent wind and the open environment permit rolling easly.