Thousands of new trees are just getting their start at Mast Reforestation’s nurseries, Cal Forest and Silvaseed Company. Long before restoration crews begin planting after wildfire, the work starts inside a greenhouse. From Etna, CA to Roy, WA this is where the results of a lot of preparation and hard work come to life.
Millions of seedlings germinating in the Silvaseed greenhouse
How a Tree Begins
As the new seedlings begin to sprout, it’s a time for celebration. Across millions of seedlings growing at Silvaseed and Cal Forest, each tiny shoot represents the first visible sign of a much longer process.
For Avery Johnson, Assistant Greenhouse Manager at Silvaseed, who oversees sowing operations, germination is one of the most exciting moments in the nursery cycle.
When you finally see germination happening, it’s exciting because you know how much work went into getting those seeds to this point. You’re looking at the very beginning of forests that could still be growing 100 years from now.
—Avery Johnson, Assistant Greenhouse Manager at Silvaseed
Avery Johnson, Silvaseed Assistant Greenhouse Manager, standing proudly in front of a greenhouse full of recently sown seedlings
Like any major milestone, this moment is built on years of careful, often unseen work. But germination is just the beginning. These seedlings still have to grow healthy, strong, and resilient before they can take root on burn-scarred landscapes and become the next generation of forest.
To understand how each seedling gets to this moment, it helps to go back to the collection of the cones that carried each seed.
Where the Seeds Came From
Long before sowing season begins in the greenhouse, cone collectors gather cones from the forest floor or climb trees across the West to gather the seed needed for future forests. Those cones are cleaned, processed, tested, and stored at Silvaseed before they ever make their way into a growing container.
Cones collected from the field being loaded into the processing facility, each one carrying the seeds that will become the next generation of forest.
This is meticulous work for a reason—essential to preparing the best seed crops to become the strongest and most resilient seedlings that will one day take their place in forests restored after wildfire.
In the words of one of our partner landowners,
They have big roots to fill.
—Rebecca Gentry, MT1 landowner
At Every Step, Timing Matters
Without the right seedlings—grown at the right time, from the right seed sources—planting projects can be delayed by years. In a world where wildfires are increasing in scale and severity, that timing matters.
In many post-wildfire landscapes, natural regeneration is struggling and unpredictable at best—and in some areas not possible because of the fire’s severity. Research commissioned by Mast found that in 2024, more than 6 million burned acres would not grow back on their own without intervention.
Seedlings are grown in nurseries first to give new forests a head start, for a stronger, more predictable rebound.
We put so much care into this process because we know what these seedlings represent. For many of us, these forests are personal. That’s why we are here early, here late, and sometimes here on weekends—because getting the timing right matters for the forests these seedlings will eventually help restore.
— Avery Johnson, Assistant Greenhouse Manager at Silvaseed
This year, the team started with ponderosa pine, then moved into sugar pine, noble fir, Douglas fir, incense cedar, western red cedar, western hemlock, and true fir species. Some species are sown earlier because they grow more slowly or need more time to fill out their root plugs, while others can be started later and still be ready in time for planting season.
This timing is intentional—guided by species-specific growth traits and years of nursery expertise—and designed to mirror natural development cycles so each seedling is set up for success in the field.
Sowing: A Pivotal Moment in a Trees' Life
Sowing is the process of placing stratified seed into soil, peat, or other media so the seed can begin to sprout and grow.
Trays of seed-filled containers traveling down the production line
Before a seed ever reaches a container, the Silvaseed team has already done extensive planning, calculating how much seed is needed based on germination rates, species, container size, and seeds per pound.
Then comes pre-sowing treatment, including stratification, a process that involves soaking seed in water and chilling it for a period of weeks or even months, depending on the species.
Seed stratifying at Silvaseed
That schedule is built by working backward from the planting date, because every seedling must be ready with healthy roots by its specific restoration window months—or even years—into the future. Miss that window, and the opportunity to replant can be delayed by an entire season.
Avery compares it to putting together a puzzle: deciding what needs to start early, what comes in the middle of the season, and what can wait until later.
Slower-growing species need more time in the greenhouse to develop strong root systems, so they are sown earlier. Faster growing species can be started later and still be ready on time.
The First Thirty Days are Critical
Once the seed is sown, the next phase begins: germination, the sprouting of a seed after a period of dormancy.
In the greenhouse, that means carefully managing heat and water. Too much moisture at the wrong moment can lead to mold, while pathogens can cause seedlings to emerge and then die, a problem known as “damping off.” The team also watches for strong root emergence, checking early for tap roots developing underneath the plug.
Millions of seedlings from the sowing line growing in one of Silvaseed's greenhouses
Preventative care matters. Silvaseed aims for 100 percent filled cells, meaning a healthy seedling in every cavity, with no empty spots in a block. To get there, some cells are sown with multiple seeds, resulting in strong germination rates, often above 95 percent.
The goal is not just to grow something, it is to produce healthy, consistent seedlings ready to succeed in the field.
Sown seedlings sprouting from their individually sown cells
Why Sowing Season Matters for Reforestation
Last month, Mast planted 6,500 ponderosa pine seedlings on the eastern Montana MT1 property, fully funded by the burial of 10 million pounds of burned, dead trees.
These seedlings were grown right here at Silvaseed nursery, meticulously cared for by Avery and her team for the better part of a year.
Last fall, Rebecca and Velma Gentry, the MT1 landowners, visited Silvaseed to take a look at their seedlings while they grew. Now, they get to step outside on their property in Montana and watch them grow in the ground.
For Avery, that is one of the most meaningful parts of the job: getting to “close the loop” and see where the seedlings ultimately end up.
At our nurseries, sowing season is not just the start of production.
It is the beginning of future forests.