JACKSON, Wyo. — The Nature Conservancy’s (TNC) work to understand optimal reseeding after herbicide treatment includes looking into a genetic mix of seeds created to establish a more resilient strain of plants.
The ongoing TNC study is aimed at testing the effectiveness of herbicides on invasive cheatgrass and seeing if reseeding is necessary to support the native plant community after treatment. According to Trevor Bloom, community ecologist with TNC in Wyoming, preliminary data is suggesting that reseeded areas are in fact showing a higher diversity and richness than areas that were unseeded after herbicide spraying.
Reseeding includes a control with no seeding, seed with local genetics, a commercially available seed and a mix of local genetics, half of which come from Grand Teton National Park (GTNP) and half of which are commercially sourced from a warmer, drier seed zone. Bloom explained to Buckrail that the seeds sourced from a different seed zone are the same species as the seeds sourced from GTNP, but contain different genetics adapted to a warmer, drier climate.
That climate is selected in line with predictions of where Jackson Hole is headed in the next 80 years due to the exponentially increasing temperatures, in order to find the most successful long-term restoration structure.
“Inherently even the term restoration implies restoring it to a previous state, where in the face of climate change and development, that might not be an attainable goal or the best goal at all,” Bloom says.
Bloom emphasizes the importance of active management, meaning managing a landscape to be more resilient as temperature conditions shift. While introducing new species that aren’t native can be very problematic, Bloom says the risk of introducing outside genetics within the same species, like Lewis flax and arrowleaf balsamroot, is very low.
This could be due to the fact that plants are polyploid, having up to six sets of genes. This means there’s already a vast amount of genetic diversity among individuals in the plant community, Bloom says. Being polyploid is also one of the reason plants can evolve into a new species faster than animals.
But despite this distinction between plants and animals, Bloom encourages people to conceptualize plants as wildlife too. And just like animals, local plants are going to need to move out of warmer, drier areas to the cooler, wetter areas they’re adapted to as temperatures increase. The problem with this, Bloom says, is that plant species migration may not be able to keep up with the pace of climate change. The U.S. Department of Agriculture (USDA) confirms that natural migration of plant species over long distances requires at least several generations.
“For species with very specific habitat needs or ranges limited by physical barriers…this may mean that the entire species could be at risk of extinction or extirpation due to climate change,” the USDA Climate Change Resource Center writes.
That’s where bringing in seed genotypes from warmer, drier zones comes in, as a type of “assisted migration.” Bloom says combining local genetics with seed mixes that already contain traits adapted to Jackson’s predicted climate explores the possibility of a climate-adaptive seed mix.
The importance of this climate-adaptive seed mix is directly tied to the local animal species who depend on the resiliency of native plants to continue providing habitat and nutrition. Kevin Taylor, a botanist and faculty with Wildlife Expeditions of Teton Science Schools, previously told Buckrail how native plants are responsible for supporting everything from the charismatic megafauna to the local insect populations.
“When you think about the biodiversity of this place, it’s rooted in the plant species in the ecosystem,” Taylor said.
While preliminary data is not yet able to confirm if the genetic mix is the most effective for reseeding, Bloom says the most critical result thus far is that reseeding in any capacity is better than not reseeding after a disturbance like a fire or herbicide treatment.
“It would just be a win if we could get any seeds on the ground,” Bloom says. “Seeding is better than letting [the habitat] recover on its own.”
