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Lecture: Weeping Grass: Narrator: Listen to part of a lecture in an environmental science class. Professor: And so it's clear that when animal species are introduced into a new environment, a new ecosystem, they can have a big effect on the organisms already present there. And the same applies to plants too. For example, let's look at Australia. Over the last couple hundred years, lots of different kinds of grasses have been introduced in Australia, and these non-native grasses compete for space with native grasses. Homeowners grow the introduced grasses in their lawns, and farmers rely on them for grazing pasture for their livestock, and even grow them as food crops. I guess I should clarify here. By grasses, I'm really talking about several different kinds of plants. Obviously, trees and bushes aren't included. But the term does include the typical grass, as we usually think of as growing in lawns or grasslands, as well as cereal crops, grains like wheat or rice, or corn. Anyway, people coming to Australia from other parts of the world brought grasses with them for lawns, for pastureland and for crops. Many of them, including agronomist, agricultural experts, preferred these introduced grasses. In fact, the early experts generally dismiss native australian grasses and thought of the local grasses as pretty pitiful specimens. What those experts didn't realize, however, was that they'd really only seen those species in pastures that had already been way to over-grazed by cows and sheep. The grass that they introduced, though, were not ... ideally suited for growing in Australia. Australia has a lot of droughts, which depending on the year, can occasionally become severe. And that sometimes makes conditions pretty harsh for plants that aren't used to dry weather. So the non-native grasses, well, they haven't had millions of years to evolve in that environment, and surviving the dry spells can be tough. On the other hand, a very different concern about introduced grasses, at least the species that survive the droughts, is that they can be quite invasive. They're crowding out other species, making it hard for anything else nearby to survive. In essence, they become weeds. So what's some Australian researchers have started doing is looking into ways to reintroduce some of the native grasses, you know, cultivate them to enhance desirable qualities and encourage people to plant them for a variety of uses, especially agricultural. Uh, to be more specific, one kind of grass that they're focusing on right now is called weeping rice grass, or just weeping grass, which is a type of wild rice. The amazing thing about grains of weeping grass is the protein they contain, more than twice the protein of varieties of rice you're familiar with and more than either wheat or corn. That makes weeping grass a very attractive potential cereal crop. Now it hasn't been fully domesticated yet. Australian researchers are still working on breeding it to select for the qualities they need. But farmers are already starting to introduce it to some markets and chefs are already experimenting with preparing it in their kitchens and that will be really exciting if they can develop it to be farmed for human consumption, especially since Australia is the only continent, well, of the continents that can support agriculture, we're not counting Antarctica. It's the only continent where none of the native plants have been domesticated as cereal crops. So in the entire history of Australia that would be a first. Now on top of that, weeping grass, like many other native australian grasses, has a lot of potential as a pasture grass, as food for sheep and cattle. The leaves are also very high in protein, and it's very ... it's very hardy. Unlike many other grasses, weeping grass thrives in soil that's relatively acidic. So farmers don't need to treat the soil growing in with chemicals to make it less acidic. And it has deep roots, which is vital for when the topsoil loses its moisture. That's actually the way they found out that it could be used for all these purposes. The reason they started studying weeping grass was because they found a patch of it that was green and thriving, during a drought year, when all the non-native species all around it were struggling to survive.