The state's black spruce seed cupboard is bare. So the Minnesota Department of Natural Resources is paying people $85 a bushel — up from $70 last year — for the cones to meet spring orders for reforesting.

The pay was bumped up to attract more people to cone-picking, and the push is on.

The DNR's stash of black spruce cones is so low that the agency is "kind of starting from scratch," said Mike Reinikainen, the DNR's forestry silviculture program coordinator. "We really need them by the end of February.

"We're getting down to the wire here."

Black spruce is a peat-loving workhorse tree across northern Minnesota, and those black spruce peatlands are very good at storing carbon, a key greenhouse gas. The lowland coniferous forests are also the year-round home of the spruce grouse as well as plants such as the carnivorous pitcher plant.

The short-needled pines are grown on public lands with working forests; they're harvested primarily for paper and packaging. The DNR uses the seeds to reforest about 6,000 acres of black spruce forest every year.

The female cones — inch-long shaggy footballs — cluster near the tops of the trees.

The trees produced a strong crop of cones in 2020 after a few weak years. But the DNR's supply is less about trees coning, according to Reinikainen, than about waning interest in picking. Cone-picking used to be a family activity, he said, a craft passed down through the generations.

"We're feeling like we're not seeing the same number of people come out and pick," Reinikainen said.

Typically the DNR directs pickers to where the spruce trees have been harvested and loggers have piled the cone-laden tops. That's the main method, he said.

But it's not the only one.

"Historically we had people that were really good at finding where squirrels were caching cones," he said. "They cache a ton. They're so industrious."

He's heard of pickers leaning a pallet of wood against a tree to lure squirrels to stash cones under it, he said.

The cones are dried at the State Forest Nursery south of Bemidji. As they dry, the seeds emerge. Then they are shaken by machine to separate out the large seeds.

In the spring, the seeds are loaded onto a helicopter and the DNR disperses them over public lands.

Black spruce are a key part of the lowland conifer forests, along with tamarack and northern white cedar, that make up nearly one-quarter of Minnesota's forestland. The changing climate and warming temperatures are expected to push the trees farther north.

Warmer winters will also make harvesting black spruce more difficult, because the forests are often located in wetland areas that need to be frozen for loggers to work in them. Warming temperatures shorten that window, according to the Minnesota Forest Resources Council.

The DNR has been studying the spruce grouse to determine their numbers in Minnesota, and the effects of climate change and logging on the birds. The birds feed in winter on the short spruce and jack pine needles.

"That's all they eat in the winter," said Charlotte Roy, DNR grouse research scientist.

Since the birds live relatively isolated in the dense forests, they have little fear of humans and will let you approach them, Roy said.

The spruce grouse population appears to be stable, but declining slightly, she said.

People interested in picking cones should contact one of the DNR's buying and drop-off stations before they start collecting to get instructions. The stations are in Warroad, Baudette, Orr, Littlefork, Tower, Two Harbors, Hibbing, Cloquet, the Minnesota State Forest Nursery near Akeley, Bemidji, Deer River and Northome. Contact information is at the DNR's website under "seed and cone collection."

Jennifer Bjorhus • 612-673-4683