Last updated: September 29, 2023
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The Seed Collectors: Harnessing the Power of Native Seeds for a Resilient Future
September 2023 - This summer, a team of three apprentice botanists were tasked with collecting tiny seeds for a mighty purpose— restoring central California native plant communities.
Plant diversity is crucial for maintaining resilient ecosystems into an uncertain climate future. In an effort to preserve plant genetic resources in central California, American Conservation Experience assembled a San Francisco Bay Area Network seed crew, powered by a trifecta of apprentice botanists— Emma Estrada, Em Mielke, and Josephine (Jo) McCormick. Following guidance from Seeds of Success (SOS), a national seed collection program spearheaded by the Bureau of Land Management, the team worked at Pinnacles National Park, Point Reyes National Seashore, Golden Gate National Recreation Area, and John Muir National Historic Site. At each, they set out to collect seeds from native California plants, such as tomcat clover (Trifolium wildenovii), purple needlegrass (Stipa pulchra), and blue wildrye (Elymus glaucus). By summer’s end, the seed crew gathered several million seeds from 12 different species, making up a biodiverse seed bank— critical for revitalizing degraded central California ecosystems into the far future.
A Microscopic Code for Resilience
Armed with garden shears and paper collection bags, the seed crew steps into a natural office each day— amongst sculpturesque rock formations and beating heat in Pinnacles’ chaparral biome; enveloped in a thick fog in Point Reyes’ coastal grasslands; or atop a windy hillside facing the wide, sweeping ocean in Golden Gate’s coastal-sage scrubland.
After scouting locations to ensure that the quality and quantity of a given population is suitable, the team gets clipping, snipping the flowering heads (aka “inflorescences”) of their target species. Each inflorescence is loaded with many seeds. They aim to gather 20% of viable seeds at their collection plots, and carefully select which individuals to clip in order to maximize genetic diversity: “It’s easy to be like, oh, this is the tallest one so I’m going to take it. Or, I don’t want to bend down, so I’m going to grab the one that’s closest to me. But you want to collect from a variety of different individuals so you’re not artificially selecting for a certain phenotype,” explains Em. “It’s also important to collect from a variety of different areas within a site. So, this is growing in a bright, sunny patch, that one’s growing in the shade. This one’s growing around a lot of invasives, so maybe it’s better adapted to handle that. It’s important to get as much variety as possible.” The team also aims to collect seeds which are at varying stages of their life cycle in order to capture specimens which are genetically predisposed to bloom during the early, mid, or late growing season.
Genetically diverse plant communities, comprised of individuals with unique traits and super-powers, are better at responding to shifting environmental conditions. Plants exhibit wide variation in temperature and drought tolerance, water use efficiency, response to pests, and other characteristics which are crucial for coping with climate changes. Ideally, this range of diversity is captured within the collections, so that these resilient community compositions can be applied onto degraded landscapes. Each and every seed collected is a treasury of genetic variability, containing key information to withstand new environmental circumstances. Scientists are interested in learning more about this genetic vault; the crew’s seed bank will also serve as a resource for research investigating what makes certain individuals more resistant to extreme climate events, such as California’s prolonged droughts.
At the end of long field days, the botanists’ paper bags are filled with carefully-chosen inflorescences.
The Seed Barn
Enter: the seed barn. The barn’s unpresuming exterior– a small wooden structure encrusted with flaky white paint– modestly houses hundreds of thousands of ecosystem-reviving seeds. After each field day at Point Reyes, the crew heaves open the creaky doors, revealing the barn’s wooden interior, warm light filtering through dusty windows and illuminating a collection of tall metal racks and seed cleaning screens. Together, Emma, Em, and Jo carefully spread their clippings onto metal trays, allowing them to dry out. After the seeds are done drying, the team packs them into manilla envelopes. “We tuck the babies into their little paper beds,” laughs Jo. Each site has its own form of a “seed barn”— at Pinnacles it is a storage locker, and at John Muir National Historic Site, a rat-proof shed.
At the end of the field season, the team ships the collections to a seed extractory, where they are cleaned and processed further. From there, the seeds will follow one of four pathways: they can be grown out in nurseries to produce a larger quantity of seed, stored, used in genetic research, or immediately applied to a landscape in restoration initiatives.
Tiny Seeds for Enormous Impact
Much of the seed that the crew collects will go back into restoring degraded areas of the landscapes where it was collected. “It’s really cool that we can collect seed and know exactly how it's going to be used and how it will help the ecosystem which it’s coming from,” says Emma.
The collections at Point Reyes, for example, will provide ranchers with native seed to rejuvenate their pastures after cows have finished grazing for the season. Oftentimes, ranchers opt to revegetate their rangeland with non-native grasses, as it is initially a much cheaper option than purchasing native seeds. These non-native grasses, however, often have shallow roots, leading to erosion of the landscape. They often aren’t able to provide services which are vital to coastal grassland ecosystems. Native grasses, on the other hand, are much better adapted to the conditions of Point Reyes. Bunchgrasses such as purple needlegrass (Stipa pulchra) and California oatgrass (Danthonia californica) use less water and can stay green for longer periods of time through the moisture provided by the Bay Area fog belt— ultimately proving to be a more economic and sustainable option for farmers. Additionally, native grasses have formed harmonious relationships with surrounding flora and fauna over thousands of years. They provide important habitat for wildlife, such as ground nesting birds.
Planting native seeds is also valuable for preventing the spread of invasive species, especially after events such as wildfire. “Hopefully, if you can get native seed first you can prevent invasive species from coming in and taking over,” says Emma. After catastrophic fires— an increasingly common occurrence due to climate change—ensuring that native species are the first to establish in a burn zone also serves to buffer the impact of high-severity fires from the get-go: “fire is only going to get worse in our lifetime, which not only means we need more plants to reseed areas after they’ve been burned, but we also need to plant way more species which survive, if not thrive under fire,” says Jo.
Much of California’s native species are fire-resilient, and have remarkable characteristics which allow them to flourish under a blaze. In the chaparral ecosystems in which the team worked at Pinnacles, for instance, many plants have fire-resistant roots, and even leaves coated with flammable resin, which help to fuel the fire up to the heat threshold needed for their seeds to germinate. Jo notes that “the other reason you want to have a lot of natives is [to have] a diversity of things to burn. Not everything is going to burn at the same time, or at the same speed, or as badly compared to if you have a field of very homogenous [non-native] grass.” Once again, this underlines the reason why programs such as SOS are important— the conservation of floristic species and genetic diversity is essential to creating resilient and adaptive ecosystems.
Nearing the end of the field season, the three botanists reflect on their experience as the first Francisco Bay Area Network seed crew. “This [experience] has been really rewarding because what we’re doing is part of the work to combat effects from improper land use and climate change…my career goal is to work in climate change mitigation, and it feels very fulfilling to be doing something like this,” says Em. Emma reflected on how her relationship with plants has deepened, noting the power in getting to know the characteristics and life stages of their target species so intimately.
While the crew knows the capability of their hard-earned seed, they continue to feel a sense of awe that this wealth of life-sustaining potential comes in such miniscule, fragile form. “Impact [in this role] feels and looks a little different [than what I’m used to]. I’m used to working in a space like [a nursery or garden], where you can very clearly see how much gardening you’ve done throughout the day,” says Jo, who used to work at Bloomington Community Orchard. “When we were packaging up all of our seeds, it was like, wow, in one small box is several million seeds … which was three months of 40-hours-a-week labor. That feels really different than the weight of dirty tomatoes in your arms,” she says. “However, being engaged in a national project and being the founding crew for it in this area does feel quite cool. I am engaged in work … that is really important when you think about all these scary climate future scenarios,” she adds.
As we move into an uncertain climate future, it is remarkable indeed, that the continuance of native central California plant communities lies in the promise of tiny, ever-resilient seeds.
For more information:
- Read more about Seeds of Success:
- Contact San Francisco Bay Area Network Botanist Kelsey Songer
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