Lack Of Native Seeds Spurs Federal Plan To Replant Fire-Loving Invasive Grasses
The proposal surprised local elected officials and conservation groups that had already been working on native seed issues.
The U.S. Department of Agriculture’s plan to pepper parts of Maui鈥檚 fire-ravaged landscapes with the seeds of invasive grasses has underscored how Hawaii has not banked enough native seeds for watershed-scale plantings.
Parts of Lahaina and Upcountry are facing the threat of significant soil runoff whenever the next heavy rains come since the Aug. 8 fires consumed so much of the vegetation that held the topsoil in place.
The USDA’s Natural Resources Conservation Service’s proposal caught the leaders of local invasive species groups, Maui County Council member and even state land officials by surprise when it came to light last week.
Council Chair Alice Lee said that it was “very disturbing information” when asked about it at a press conference Thursday.
Council member Tamara Paltin, who represents West Maui, said she hopes there will be a discussion with conservationists and community members who live in the affected areas.
“This is the first that I heard that the stabilization involves replanting the invasive grasses that contributed to those fires,” Paltin said Thursday. “I don’t know that that’s been vetted by the community.”
Efforts are already underway to restore sections of the burn area with native and non-invasive flora. Community leaders don’t doubt the need to minimize erosion but replanting invasive grasses would present a major dilemma.
Non-native grass species have been a longstanding conservation concern, given they choke out native flora and drive Hawaii鈥檚 statewide vulnerability to wildfire.
The plan still needs to be put to all the relevant landholders, federal officials said Monday, and there are plans to consult with county and state agencies.
Coordinating with the Department of Land and Natural Resources, the Hawaii Department of Agriculture and Maui County is the goal moving forward, according to Michael Constantinides, USDA’s NRCS Assistant Director of Technology.
The NRCS work falls under the and is being conducted at the behest of the Central Maui and Olinda-Kula Soil and Water Conservation Districts.
“First we’ll try finding species that are available locally. Those quantities will be limited. So that needs to be something that everybody understands,” Constantinides said in an interview Monday.
It is likely that the balance of plant material will need to come from the mainland.
No matter the source, the USDA would ensure screening and testing would be done to “make sure that weeds and other unintended species are not included,” Constantinides said.
The USDA would not say which species it was considering for dispersal, though it would not recommend species that “don’t already exist in significant quantities on the landscape,” he said.
More details are expected to be released in the next few weeks.
Hawaii’s Need For Seed
Many of the state驶s conservationists acknowledge the harsh reality underpinning the plan: Hawaii has insufficient seed bank stores to restore thousands of acres to its native state.
“It would be awesome if we had a load of pili grass seed and just dump it on there, but we just don’t have it,” University of Hawaii wildfire researcher Clay Trauernicht said.
But for the past few decades, conservation efforts have focused on rare and threatened native species of plants in Hawaii, not “common or matrix species,” according to Matthew Keir of Hawaii’s Division of Forestry and Wildlife.
Keir says he and his colleagues have confronted the seed shortage before.
“It’s no surprise, right? That’s exactly what we’re talking about: We do not have adequate supplies of native plant material to substitute for (invasive species),” Keir said.
Those workhorse plants 鈥 like ohia 鈥 lay the foundation for native ecosystems but conservation groups realize there is not enough stock to help the waning populations recover.
“Unfortunately the fires have showed us the work that we should have been doing on Maui.”
Matthew Keir, botanist with Hawaii’s Division of Forestry and Wildlife
A confluence of pressures on the landscape persist after the Aug. 8 fires, including axis deer populations, which have been eating down the regrowth of non-native plants.
Constantinides said that NRCS has not evaluated the seed banks of species that were affected by fires, though it found in Pulehu that “almost 100%” of the resprouting non-native grasses were being eaten down by deer after being weakened by fire.
It is likely that fencing projects will also be part of the regional NRCS proposal, which requires sign-off from USDA national headquarters.
“They are very stressed and if they continue to get grazed by deer, then they will probably die off and there will be no plant life on that landscape,” Constantinides said.
Any work recommended in the proposal “won’t happen without the landowner’s concurrence,” he added.
Central Maui Soil and Water Conservation District Chair Mae Nakahata said the proposal for seeding plants like non-native buffelgrass would likely apply to ranches affected by the fire mostly, not necessarily to places like vacant land surrounding Lahaina.
In this case, “I would not call it an invasive but a valuable forage species,” Nakahata said.
But because buffelgrass might be able to establish itself quickly, in light of drought, it was considered the best seed to disperse to stem drought and regrow feed for cattle on fire-affected ranches, Nakahata added.
“Later on you can evolve the landscape but at least you have the quick protection, which is what everybody needs right now,” she said.
USDA could also recommend a “short-lived or temporary species as part of a seeding mix,” which is used nationally and has “little or no potential to become naturalized or established,鈥 Constantinides said.
The maintains a list of 78 different native species that would be helpful in larger scale restoration work, such as koa, ohia, and aalii or pili and kawelu grasses.
But the 16 seed banks under its Hawaii Seed Bank Partnership are run by conservation groups that largely store seeds for their own programs, not for the problem that Maui imminently faces, Laukahi network coordinator Kimberly Shay said.
, seeking to understand what the conservation communities鈥 need is for native ecosystem work, including landscape-scale, post-fire restoration.
Such an effort will likely require teams of collectors to continuously forage suitable seeds for planting across multiple climates and landscapes and appropriate facilities to store them.
Keir said that would require an annual operating budget of a few million dollars, with an upfront investment of between $10 million to $15 million to bring the seed banks up to par and create a central depository for bulk collections.
“We have maybe 30 years of native seed research here that shows us the way forward,” Keir said. “We really want to get ahead of this. Unfortunately, the fires have shown us the work that we should have been doing on Maui.”
Civil Beat鈥檚 coverage of climate change is supported by the Environmental Funders Group of the Hawaii Community Foundation, Marisla Fund of the Hawaii Community Foundation and the Frost Family Foundation.
“Hawaii Grown” is funded in part by grants from Ulupono Fund at the Hawaii Community Foundation and the Frost Family Foundation.
