Fort Hunter Liggett in California holds thousands of acres of grassland habitat and oak savannah within its borders, land that supports numerous species of vegetation and wildlife, including the second largest elk herd in the state. From a military perspective, these ecosystems offer quality training in a natural setting, typifying a Mediterranean-type climate. From a natural resources perspective, California’s grasslands and oak savannahs are declining in both amount and quality, threatening the animals and plants that depend upon them. Vernal pools, or seasonal wetlands, occur frequently in these grasslands, providing habitat for many species including the federally listed vernal pool fairy shrimp.
Since the non-native yellow star thistle was introduced to California in the 1800s, it has invaded 25 million acres of grasslands and oak savannah, crowding out native species and hampering soldier training. From the time it was discovered at the Fort, it spread to 20,000 acres in just 5 years. Besides overrunning native vegetation, the plant causes other problems: its thorns are sharp enough to rip clothing, the plant is toxic to horses, and cattle cannot eat the plant because it sticks in their throat. Worse, it’s prolific. Each plant produces about 5,000 seeds which can lay dormant for up to 5 years.