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The Why of Iowa's White Pines

Last spring, I had the opportunity to lead researchers from the USDA's Plant Introduction Station in Ames, Iowa out to one of our rarely visited properties in search of authentic, Iowa white pines. The plant introduction station works to find and collect local ecotype specimens of certain plants with the goal to preserve the natural genetic diversity.

So what does that kind of work look like? Well, one day in early April, it looked for researcher Jeff Carstens like waking up at approximately 3 AM to make the drive from Ames to Northeast Iowa, armed with a “big shot” slingshot which he would deftly use to fire a small cutter ~60' into the crown of mature white pines so he could collect a small branch for genetic analysis and potential grafting to grow new baby trees at a forest service nursery in Northern Wisconsin.

Jeff snagging a scion from high in the canopy

Meanwhile, the Iowa DNR has their own white pine project running in parallel to the scion sampling underway at the USDA. Forester Aron Flickinger has likewise made several trips from central Iowa to scout for local white pine specimens from which he can collect seeds during the short window of ripeness. Their goal, like that of the plant introduction station, is to preserve the unique genetic traits that have allowed white pines in Iowa to thrive for thousands of years right at the southern end of the range for the Great Lakes ecotype.

Range map of the eastern white pine

Both projects have some of the same challenges. White pines are a disturbance-loving species, sprouting in full-sun conditions but growing very slowly compared to their other pioneer species brethren. In the absence of fire, grazing, or heavy logging, the native white pines have begun to age out and a look in the understory of current pine groves indicates poor natural reproduction of the next generation.

Trying to separate the naturally-occurring white pines from their nursery stock counterparts further complicates the matter. Trees in general tend to outlast the humans that planted them, and we generally don't leave a note. If somebody planted a white pine on their property 100 years ago, and then nature reclaimed the tree's surroundings, it might look as natural as anything else.

For an example, take a walk out at the Volga Wildlife Area. A large grove of beautiful, mature white pines looks scattered haphazardly on a hillside overlooking the Volga river. But as I walk Jeff and his assistant out to this stand, slingshot in tow, Jeff immediately becomes skeptical that the trees seeded there naturally.

“One of the first things I look for is the root flare. We try our best, but humans are pretty bad at planting trees,” Jeff says examining the massive stems of the gorgeous conifers. He's referring to the spot where the main roots attach to the trunk of the tree. Humans often bury seedlings a little too deep, which damages the tree's long-term prospects but does make for a handy signature when identifying older planted trees.

Natural root flare on an eastern white pine

"The needles are a little different too," Jeff explains. In his experience, where we can know the site history like at White Pine Hollow State Preserve between Guttenberg and Luxembourg, the bundle of five needles are a little tighter on Iowa natives, whereas planted stock (historically sourced from the Northeastern US at a similar latitude to Iowa) has more widely spaced needles, like an open hand.

Needle bundles on an Iowa white pine

That all comes in the abstract, of course. Trees, like humans, have plenty of natural variation. Then there's the matter of hybridization, a further confounding variable where cross-pollination could lead to offspring with characteristics from a little bit of both.

Long story short, the experts don't always agree, as is the case at our own Volga White Pines preserve, a conservation easement for which the CCCB has been entrusted stewardship. Foresters have long suspected the small stand of white pines on the site were naturally occurring. Jeff wasn't so sure.

"I'm seeing girdled roots, lots of recently-shade-pruned lower limbs..." Jeff intimates, scratching his chin as we wander under the dense shade of the mature trees. The girdled roots can happen naturally, but they often signify inadequate planting technique. The bare branches lower on the trunk indicate the trees might not be as old as we once thought. Jeff fires the slingshot and lops off a few samples anyway; the genetic testing will offer more certainty than even the most knowledgeable eye test.

Girdled roots from an inadequate planting

The best bet short of a laboratory is the context. That's where DNR forestry program specialist Aron Flickinger has focused his scouting efforts. On some sites, like Yellow River State Forest, we have a long enough site history to know how and when various pines came to grow. On other sites, a little common sense goes a long way.

White pines (and cedars) overlooking the upper Iowa river near Bluffton

Leading a volunteer training at the Osborne Nature Center, Aron and district forester David Bridges explain that a lot of the good candidate trees exist on sites where the terrain precluded humans from intervening - rocky outcrops where plows couldn't go, especially.

Of course, most of these sites present extra challenges to harvesting material from the tree.

The trees typically produce cones in the upper third of their crown, so it takes a sharp eye to spot them. Then it takes an awfully sure-footed arborist to climb the 100' tall tree perched precariously over a vertical cliff face along area streams and rivers. It takes a heck of a talented slingshot user to shoot through the canopy into the top of the crown. All this to say nothing of the significant trek typically required to get to these kinds of sites.

White Pine Hollow. Note the root flares and lack of lower limbs.

Which makes volunteerism especially critical to the success of both the USDA and the DNR's effort to find native specimens, and alert seed collectors when the short ripening window (usually two weeks or so in August) begins during a boom year.

White pine cone ripening

But one question vexed me throughout my conversations with Jeff and Aron, consistently getting buried behind a million other questions about the ecology and process:

Why white pines?

After all, Northeast Iowa grows some of the finest hardwood trees on earth. Part of the reason these projects have such challenges is because in the northern parts of their range, Red Squirrels cache white pine seeds en masse, making it extremely simple to find large quantities without the use of climbing gear or a fancy slingshot. We have no such squirrels. If white pines aren't a staple of the local fauna's diet, and they don't necessarily represent a hugely important timber tree (around here, anyway), why go to such lengths to preserve those genetics?

Of course, I'm a staunch advocate of diversity for diversity's sake. The more parts of nature's web we keep in place, the stronger the web becomes in the face of adversity. Like most conservationists, I also find diversity and the subtle differences in phenotypes plenty fascinating in its own right.

Local ecotypes matter because those ecotypes have special adaptations allowing them to thrive under certain conditions. But trees live a long time, and the conditions here are changing away from them more rapidly than adaptation could prepare subsequent generations.

Foresters across the world have had the phrase "assisted migration" on their lips ever since climate change has started wreaking havoc on their forests. It refers to the intentional planting of tree ecotypes or even whole species north of their natural range to try to get ahead of the changing climate. I wondered why, then, Iowa foresters would put so much effort into preserving the adaptations of Iowa white pines when future conditions will likely evolve away from what makes them work, here, now.

"The forestry folks up in Michigan, Minnesota, and Wisconsin are watching this project pretty closely," David explains to the group of volunteers. I smacked my forehead. Of course! I'd been (hopefully uncharacteristically) narrow minded in my conception of the project. The Great Lakes ecotype of Pinus strobus, the type we have here, is a keystone of the northwoods. We get our share of rough winters, but Duluth has it a lot harder, and the trees there now are adapted to those harder winters.

White pine stand in Minnesota

But 30, 50, 100 years in the future (a white pine might live 200 years) the winters might look drastically different. If we can secure a stock adapted to the "milder" winters of Northeast Iowa, perhaps we can maintain that component not only in our forests but those forests well to the north of us as well.

Foresters, and restoration ecologists generally, must take a long view and I felt dumb (a familiar feeling most days) for failing to see the forest for the trees on this one. The decisions made now from a forestry perspective will ripple through multiple generations. Preserving the unique genetics of our stately and ancient white pines is not just an academic exercise, but an immensely practical one.

The more types of adaptability we can cultivate, the better prepared we'll be to adjust to future conditions. It's hard to predict the future, but if we can have a thorough inventory of the present, we can hopefully be ready for whatever it brings.

If you think you've got a good candidate on your property - note that yard trees are not likely naturally occurring stock - feel free to reach out! Call us here at the Osborne Nature Center or email with as many details on the specimen as you can provide.

Looking Back

Kids Camp on July 2nd introduced "budding naturalists" to the real life and day-to-day work of a county conservation board naturalist. Hopefully these little nature-lovers got a new answer to the question of what they want to be when they grow up!

Junior Naturalist Camp wrapped up July 6th-8th with an adventure along the Turkey River. Campers got their first taste of backpacking, learning the principles of leave-no-trace dispersed camping along with some outstanding campfire cuisine and ample time on the Turkey River to cool off during the heat wave.

The Nature All Around Us art series continued with an Eco-Printing workshop hosted by naturalist and art savant Abbey Harkrader. Participants used natural materials to dye cloth, discussing the best plants and methods for getting some truly funky results courtesy of mother nature.

This month the Motor Mill Foundation launched an online fundraiser for the restoration of the Motor Mill Inn! We hope to raise $3000 through the fundraiser by August 15th to become eligible for $100,000 in grant funds the "community thrives" program. If you're interested and able to make a donation, check out the details here.

The Clayton County Archers hosted a 3D Archery Shoot July 18th at the Osborne Archery Range. The archers always set up an amazing course utilizing an array of different animal facsimiles and moving targets. Results and info on future events posted on the CCA website.

We got a special visit from Iowa's Lieutenant Governor on July 21st to discuss director Jenna Pollock's "Attracting Success" initiative geared towards recruiting and retaining the next generation of talented professionals to Northeast Iowa. When you've got a bigwig's attention, you know you're doing something right!

The O.W.L.S. got a chance to see how the voyageurs plied their trade before railroads and interstates made life a lot easier with a Voyageur canoe trip around Prairie Du Chien's St. Feriole Island. Many thanks to Clinton County Conservation for providing the gigantic canoes and some additional instruction. If you've ever tried to share a canoe with just one other person, you know it's no small feat to get everyone's paddles on the same page.

Field Day Friday at Bloody Run County Park allowed restoration enthusiasts to see one of my personal favorite success stories at any of our parks. The remnant oak savannas gracing the blufftops put on quite a show all year round and, despite Murphy's Law making the program overlap with the one of the few rainy days we've had all year, the enthusiastic group came with great questions, observation skills, and sure feet.

Looking Forward

Firebreaks get mowed this month! This may seem like a weird thing to mention, but there's nothing like the prairie in high summer - if you can enjoy it. The firebreaks go unmaintained most of the year to facilitate bird nesting, making it difficult to enjoy the prairies unless you're willing to wade through thick vegetation. The few weeks right after they get mowed each year offers a great time to get out and enjoy peak bloom without "enjoying" peak bug.

Hunter's education classes will take place this month August 9, 11, 13 & 14. Mon-Wed-Fri (6pm-9pm) and live fire field day and test for certification on Saturday at Osborne Pond (7am till noon) Online registration is only available through the Iowa DNR website.

The Master Conservationist Program hosted through Iowa State University Extension kicks off this month at Osborne Park. This program will highlight conservation history and current best practices and is a great fit for anyone interested in better understanding and managing their wild places.

The Osborne Kids Camp programs will continue on August 13th with an "undercover critters" program. Crack the secret codes of animal calls, markings, and scents. Learn how animals use their super senses.

Join the O.W.L.S. on August 19th as they charter the Maiden Voyage for a fun afternoon on the Mississippi. Participants will learn about commercial fishing, clamming, early explorers and wildlife up close and personal. Reservations are required at 245-1516, so call early to ensure a spot.

Field Day Friday this month will take place at Motor Mill on August 27th. Highlights and discussion will focus on the Grau memorial savanna and the adjacent prairie reconstruction. Meet at the Motor Mill campground at 5:00 PM.

Painting with Abbey will welcome visitors to the Osborne Nature Center on Saturday, August 28th for some nature-inspired art projects just in time to get the juices flowing before fall color season.

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