Native plants need sunlight and water to grow, but they also need another important thing: room. If an individual plant only used the soil directly below it to spread its seed, it would soon be overcrowded and run out of light and water. But plants are smart adapters – they use a variety of methods including wind, gravity, wildlife and water to disperse their seeds farther distances, giving the next generation of plants more space and resources to thrive.
The variety of plant species in the Irvine Ranch Natural Landmarks is incredibly diverse, and so are the ways in which these native plants disperse their seed. Arroyo lupine’s seed pods buckle and twist as they dry out in the sun, eventually popping open and sending seeds flying. Cobweb thistle have pappus – tufts of hair on their seeds that resemble parachutes – that help their seed glide along with the wind. Other flowers such as dandelions use this method as well, but cobweb thistle pappus is much larger in size so it can catch enough of a breeze to carry the plant's bulky seeds. Gravity is the main seed-spreading tactic for other native plants such as black sage, whose seed drops to the ground and is occasionally transported longer distances with the help of harvester ants. Many native plants have different ways to attract animals to spread their seed. Bush sunflower doesn't smell like much when it's blooming, but once the seed is ripe it emits a strong, sweet and musty smell. Scientists still aren't sure exactly how bush sunflower disperses its seed, but many suspect this change in smell is a signal to birds and small seed-eating mammals that the seed is ripe and ready to go.
Volunteers have already spent many hours collecting seed from arroyo lupine (Lupinus succulentus), bush sunflower (Encelia californica) and chia (Salvia columbariae), and harvesting season continues through the end of December. In June, the seed of the cobweb thistle – one of the few thistles native to the Landmarks – will be ripe for harvesting! Cobweb thistle (Cirsium occidentale) ready for harvesting is easy to spot – instead of the flower’s unique pinkish-purple bloom atop the stem, volunteers will see the large white, fluffy pappus prominently on display. You can find a list of all upcoming volunteer opportunities at the Native Seed Farm by clicking here. Activities occur every Wednesday and Saturday morning, and all tools and training are provided. Volunteering at the Farm is an ideal way to connect with the outdoors as summer temperatures heat up – no hiking is required, many activities are family friendly, and the farm often enjoys a nice breeze.
All programs are free with required pre-registration, which closes at 4 p.m. the day prior to the event. Children as young as 8 years old are welcome to volunteer on the farm, and must be accompanied by a parent or adult guardian. For more details on programs at the Native Seed Farm, click here or visit LetsGoOutside.org/activities.