Skip to main content
U.S. flag

An official website of the United States government

After the fire come the precise planting of seedlings

Kathryn Sosbe
Office of Communication, U.S. Forest Service

Overlooking the Lucky Peak Nursery that grows seedlings that will be replanted in forests where they are needed. All great actions start with a seed of an idea. In reforestation, the action starts with a seed. Literally.

After a fire, trees that haven’t been destroyed often have the ability of producing the seeds needed to grow into future stands, or clumps of trees. But often nature gets a bit of help from the U.S. Forest Service.

“The Forest Service is in the business of managing the people’s land,” said Clark Fleege, manager of the U.S. Forest Service’s Lucky Peak Nursery northeast of Boise, Idaho. “We want to manage the land in such a way that forests are healthy and are sustainable. In some cases what we do is accelerate the rate of restoration through the seeds we have collected and stored.”

It sounds simple, but it’s a long and often precise process. It takes a minimum of one year before seeds that have been stored in the 60-acre seed bank – sometimes for decades – become 4-inch seedlings viable enough to be replanted in the forest.

Lucky Peak is one of six geographic dispersed Forest Service nurseries that act as seed banks. Deposits are made by ranger districts, which are the smallest units on a forest. Ranger district employees must ensure a 10-year supply of seeds is stored in the bank ready to be used when needed.

Seeds are carefully collected and labeled so that when they are needed, they are replanted in the area exactly where or very near to where they were harvested. In fact, in addition be being geographically replanted in the same area, seeds are planted at the same elevation within 700 feet from where they were collected. That means a ponderosa pine seed collected in Colorado would not be planted in Idaho. Or a ponderosa pine collected in Northern Colorado would not be replanted in Southern Colorado.

“If the districts have done a good job of collecting seeds when they are ripe, and we’ve done a good job of processing them where we don’t damage them and we store them in sub-zero temperatures, then those seeds will be viable for 30 to 40 years without a problem,” Fleege said. “The important thing is that everyone has to do their part right.”

A worker harvests seedlings in a seed bank.

When a district finds a need to plant seedlings, such as during reforestation efforts after a fire, they order the seedlings from the nursery. Fleege and his staff go to the seed bank, find the ones collected from the area the district has identified and begins the process.

“We keep them in six milliliter baggies in a freezer stored at 10 degrees,” Fleege said. “Put a bunch of peanuts in a baggy and put them in a freezer. That’s what it looks like.”

Once carefully thawed and inspected, the seeds are planted in holes made in large Styrofoam blocks. Each block has 112 holes. Those blocks lay end-to-end in the glass greenhouse, where workers nurse them along until the next viable planting season. That means the seedlings will not be ready to plant until at least one year after a fire.

Fleege said that if a fire occurs in August of this year, the seeds to reforest the area could be planted in the nursery in the spring of 2014. The seedlings would then be ready to replant in the forest in the fall of 2014 or the spring of 2015.

“It’s not like a fast-food restaurant where you can just drive though at a moment’s notice,” he said. “There is no way of forecasting where or when a fire will occur or how many plants will be needed.”

However, working closely with district rangers, the nursery maintains an extensive collection of seeds. Millions, if not more, of them.

“Take a ponderosa pine, and this is only one example. When the district collects for ponderosa pine, generally a bushel of cones will yield a pound of seed,” Fleege said. “And a pound of seed will produce 5,000 plant-able ponderosa pines. And we usually plant 300 seedlings per acre. Our seed bank now has about 10,000 pounds of seeds.”

Fleege also said they simply don’t walk away after a seedling is planted. Each new planting area is revisited in the second, fourth and fifth years after replanting to ensure long-term viability. If replanting is necessary, then they thaw more seeds.