Let the Grass Rest! Battling Invasive Plants

Invasive grasses and weeds have been slowly moving into California's pastures, making things harder for the local grasses that livestock have relied on for generations. Now, researchers are saying that if farmers let the grasslands rest, they can get healthy enough to resist invasion.

That's at least according to a study recently published in the journal Ecological Restoration, which details how the prevalence of native perennial grasses can increase by an estimated 72 percent in a region where cattle grazing was moved, in order to give pastures a break.

According to the study, annual grasses live their short lives quickly, growing and expanding at a faster rate than native perennials and then dying off before the year is done. This gives them a natural advantage over longer lasting grasses, as they have no need to recover from the damage inflected on them by grazing cattle and other livestock.

However, while it may sound like a good idea to just let the annual grasses become the top dog, the roots of perennial grasses grow deeper, they hold water longer, and they can stay green into hot and dry months. This gives ranchers much needed security for lean times, as California has been suffering from a wave of one of the worst droughts on record.

"By managing for perennial grasses we tend to increase the productivity of our ranches, their beauty, and their resilience against drought," Joe Morris of T.O. Cattle Company recently explained in a statement. "The flip side of this is better performance for our animals and more profit for our business. These are the hallmarks sustainability."

So how can ranchers like Morris keep their perennial grasses around?

According to the study, Point Blue Conservation researchers helped TomKat Ranch near Pescadero, Calif. start rest-rotational grazing back in 2011. This involved moving dense populations of cattle to a new small, divided pasture every 70 to 120 days, letting other pastures rest during that time.

This not only resulted in more local grasses, but it even improved the grasslands' water and carbon storage, the researchers reported. They now hope that this evidence will convince other ranchers to give this practice a try.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).