DAVIS — A frozen forest, preserved as tiny seeds packed in tall stacks of labeled boxes, holds the future of California‘s scorched woodlands.
With wildfires consuming trees at an alarming rate, the role of the sub-zero repository at the California Department of Forestry and Fire Protection’s Reforestation Center is taking on new urgency.
It stores over 42,000 pounds of pristine seed collected from the state’s native conifers, from coastal redwoods to alpine firs. An adjacent facility holds young oaks and other hardwood species. The center’s goal is to help private landowners restore their charred landscapes — rebuilding forests too badly burned to regrow naturally.
But much more is needed. After decades of forest mismanagement that created an era of megafires, there’s a critical shortage in quality seed stock, trained personnel, storage and growing space for tiny seedlings.
“The demand far exceeds the supply,” said Cal Fire forester James Scheid, who manages the center’s Reforestation Services Program. Three-quarters of requests to the center go unfilled.
A recent analysis found that 4 million acres of public and private lands in the Sierra Nevada, North Coast and Cascade Mountains burned from 2018 to 2021 — and, of that, 1.5 million acres, or 37 percent, were scorched by ultra-hot flames. That tally by consultants Mason Bruce & Girard does not include this summer’s massive Park Fire in Butte and Tehama counties, which claimed another 430,000 acres.
Dead trees don’t produce seeds, and the high-heat burn patches are too large and far away from live seed sources.
Unable to naturally regenerate, the 1.5 million acres of burned forests will stay ghostly for years. They’re dangerous for hikers and campers. Over time, there’s erosion, and invasive brush moves in.
“There’s a moral imperative for human involvement at this point,” because decades of fire suppression have created overcrowded forests that burn quickly and intensely, said Leana Weissberg of the conservation nonprofit American Forests.
Decades ago, before environmental regulations reduced logging in forests and the timber industry collapsed, there was a bustling business of nurseries.
At its height, the U.S. Forest Service had 13 tree nurseries in the nation; today, only six remain, including one in Placerville.
The state of California once supported three tree nurseries — in Ben Lomond, Magalia and Davis — which produced about 6 million trees per year for landowners all over the state. Now two of these nurseries are gone, casualties of a long-ago state budget crisis.
The Davis-based reforestation center, adjacent to Interstate 80, remains. But it can grow only 250,000 seedlings a year. To replant just 25 percent of California’s private forestlands, it needs to expand its capacity 300 percent.
Its trees are restoring replanting landscapes damaged by some of the state’s largest and consequential fires: Valley, in 2015; Camp, 2018; CZU Complex, 2020; August Complex, 2020; Glass, 2020; Creek, 2020; Caldor, 2021, Lava, 2021 and Mosquito, in 2022, among others.
To meet growing demand, the center is in the early stages of a multiyear upgrade — expanding its Seed Bank, building new greenhouses and buying state-of-the-art processing equipment.
Meanwhile, American Forests is collaborating with the state and federal government in the Reforestation Pipeline Partnership to boost seed collection, processing, storage, nursery production and planting.
This year’s collecting season is off to a robust start. Conifers reproduce intermittently — and this seems to be a banner year for Ponderosa pine, sugar pine and Jefferey pine. Across the state, foresters are peering through binoculars to survey the tips of branches, heavy with cones.
Already, 2,000 bushel bags of cones have been collected by Cal Fire foresters. By comparison, last year was lean, yielding only 210 bushels. In just two days this week, American Forests collected 157 bushels in El Dorado National Forest, near Placerville.
At least 75,000 bushels are needed to fully restore California’s burned acres, Weissberg said.
“Whenever there are good years, we want to capitalize on that,” she said.
Collectors don’t take just any cone: only the best of the best will do.
At each site, they inspect a sample. If cones are curved, like a banana, that indicates insect infestation. If they’re too green, the hardened case won’t open. If they’re too old, seeds have already scattered over the forest floor.
Some cones are sent back to Davis to be X-rayed. Inside each cone are dozens of seeds, and scientists search for healthy embryos.
If judged acceptable, there’s a brief window — only several weeks — to retrieve the cones at peak maturity.
Climbers reach into trees’ canopies to pluck the cones, which are loaded into bushels, each labeled by name and “seed zone” location. The bushels are trucked to facilities and laid out in sheds to dry.
October starts the processing and seed extraction season. A kiln, a giant chute that blows hot air, bake the cones to accelerate drying. Each species has its own precise needs. For example, Sugar pines are heated at 95 degrees; Ponderosa pine at 90 degrees; and Douglas fir at 85 degrees. Sequoias and cedars need no heat at all.
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A large tumbler spins and breaks the dried cones, so seeds fall out. A handmade vibrating, vacuum-powered seed blower cleans and “de-wings” the seeds.
Special care must be taken with some sensitive seeds, such as cedar. Ponderosa and Jeffrey pine seeds are tough. Coulter pines — the divas of the conifer world — won’t release seeds unless their giant cones are submerged in hot water.
When finished, the seeds are sent on their way.
Some are dried, packaged, labeled and placed in long-term storage in the Reforestation Center’s frigid and fragrant seed bank. The bank holds a planting stockpile and protects precious plant genes from the vagaries of climate change and possible extinction.
Other seeds are prepared for immediate restoration work.
Starting in November, each species must be coaxed into a winter nap. Some only need seven weeks of cold refrigeration. Others, such as Sierra Nevada’s sugar pine, demand 16 weeks.
Between February and May, the seeds wake up from their slumber, germinate and sprout. As they grow, they’re moved from greenhouses to larger “shade houses” and then outdoors, toughening up along the way. There is constant monitoring for signs of pests or disease.
Planted into the ashen soil, the future forest continues to need human help: soil amendments, watering, weeding, protection from hungry animals and more.
“It would be great if Mother Nature did all the work and we could just step aside,” Scheid said. “But we’ve been forced to get more and more engaged.”
“Forest Regeneration Starts with the Seeds” by Cal Fire’s Forestland Steward:
“Long-Term Economic Impacts of Large Fires in California from 2018-2021” by Mason, Bruce & Girard:
Originally Published: