But park officials say they contribute to erosion by damaging plants and soil.
It means all ground cover by plants, and is the main element of the biosphere.
There was a large reservoir of water beside the station, kept fresh by growing green plants and selected fish.
He is known for his research involving the absorption of nitrogen by plants.
He found an unoccupied niche on the second level made private by green plants, and opened the channel.
By growing plants in different layers, the farmers make best use of the soil and water.
It is hardy and not easily outcompeted by other plants.
Several small fires broke out, quickly smothered by surrounding plants.
There is also an invasion by non-native plants in these forests.
Children, being smaller than adults, are more susceptible to poisoning by plants and seeds.