Forests burned by wildfires sometimes need a little help to recover and regenerate. Even when some trees survive amid hillsides of blackened stands, they are often not able to drop enough cones to reseed the next generation of forest. The U.S. Forest Service has found that cones collected from healthy trees in nearby areas can be used to bridge the gap.
Toward that end, the San Juan National Forest contracted this year with Dr. Spruce Lore Axe Tree Service, a small business based in Spokane, Washington, to send certified climbers to the tops of trees. The cones they plucked this fall will become the seedlings of the future, but first they had to take a trip to Nebraska.
There, at the Charles E. Bessey Nursery, the oldest federal seedling nursery in the nation, the cones are stored in a cool, dry place until they open. Then seeds are separated from the cones with screens and shakers and cleaned. At that point, the seeds are ready for labeling and storage until the national forest calls for them.
“We only plant seedlings grown from cones native to the San Juan, because they are uniquely adapted to our climate and location,” said Gretchen Fitzgerald, San Juan National Forest forester. “Cones from other areas are genetically different, and their seed will not survive or thrive as well as our local varieties.”
Some of San Juan forest’s seeds will be stored in Bessey’s regional seed bank; others will be planted in the nursery’s 46 acres of irrigated seedbeds or controlled-environment greenhouse. Seeds planted in January will be ready to be shipped to the forest as seedlings by the next spring or fall.
This year’s cone collection concentrated on areas of the national forest north of Durango, near Vallecito, and southeast of Pagosa Springs. Species of tree were selected based on which kinds of seed are underrepresented in the seed bank compared to upcoming reforestation needs. In addition, the foresters are prioritizing the collection of spruce cones, because so many Engelmann spruce trees are dying from a current bark beetle infestation.
“We begin actively scouting each year for a cone crop in mid-July,” said Beth Vance, San Juan National Forest forester. “There’s a very short window for collection. We have to collect cones after the seeds are mature but before cone scales begin to flare and release the seed.”
The certified climbers are sent up healthy trees at certain elevations individually selected by foresters. Trees targeted for cone collection must be free of deformities, insects and disease to offer hardy genetics. Foresters also sample the cones that come down for seed viability.
“To determine seed ripeness and maturity, you cut open the cone and look at the seed,” Fitzgerald said. “The embryo should fill the seed casing up by 90 percent, and the seed case should be slightly brown. The seed itself should be milk-white and not too soft.”
This fall’s harvest included 22 bushels of Engelmann spruce, three bushels of Douglas fir, 18 bushels of limber pine and 51 bushels of ponderosa pine cones. Some will be stored at the Nebraska nursery; others will return as seedlings soon to help reforest areas burned by the Missionary Ridge, Vallecito and Little Sand fires.
Ann Bond is the public affairs specialist for the San Juan National Forest.