Restoring Cottonwoods to the Missouri River – Part 1

Last week, I had an experience that doesn’t come often to a prairie ecologist.  I participated in a tree planting project.  Well ok, we weren’t exactly planting trees, but we were laying the groundwork.

Collecting cuttings from cottonwood trees for a Missouri River restoration project. This is a panoramic made from two photos stitched together. Click on the photo to see a larger version.

It’s kind of a long story.

Over the last few years, The Nature Conservancy has been working with the Natural Resources Conservation Service (NRCS) on wetland restoration projects along the Missouri River in eastern Nebraska.  Tyler Janke, a Conservancy employee, has – among other things – helped design, implement, and evaluate restoration projects implemented through the Wetland Restoration Program (WRP).  One of Tyler’s major contributions has been to facilitate the use of high-diversity seed mixes at a number of sites.  I’ll write more about that effort another time.

As the number of WRP projects has grown along the Missouri river, one important lesson has been learned by the Conservancy, the NRCS, and other partners.  Although the traditional model of wetland restoration in Nebraska has been to convert wet crop fields to wetlands dominated by grasses, sedges, and other herbaceous plants, that model has turned out to be inappropriate in many places.  Why?  Because most herbaceous plants can not survive the kind of frequent and severe flooding that occurs in some portions of the Missouri River floodplain.

So what to do?  Trees.  Tyler and others have modeled the floodplain and identified areas where frequent flooding and sediment deposition are likely, and those areas are being proposed as places where cottonwood woodlands should be.  Cottonwood woodland has disappeared from much of its historic range along the Missouri River, and what remains is largely stands of old trees.  Over time, the lack of young and middle-aged stands of cottonwoods will lead to a drastic change in habitat for many species in the Missouri River valley.

No problem, then.  We need more cottonwood woodlands, we can’t get grass to survive in many places anyway – let’s just plant those areas to cottonwoods, which are better at surviving flooding and sediment deposition.  Well, as it turns out, there are quite a few questions about how best to do that, and what the cost effectiveness of various methods are.  That’s where Tyler comes in again.  Through a partnership between the Nebraska Forest Service, the Arbor Day Foundation, and The Nature Conservancy, Tyler is leading an effort to create experiment and demonstration sites for Missouri River cottonwood restoration.  Funding for the project comes from the U.S. Forest Service, the Arbor Day Foundation, and State Wildlife Grant funding through Nebraska’s Natural Legacy Project.

I’ll summarize the entire project design in a future post, but suffice it to say that over the next three years, we plan to establish 300 acres of new cottonwood woodlands on WRP lands.  We’ll experiment with a variety of methods, including the planting of cottonwood cuttings and seedlings.  And that – finally – brings us back to what I was doing last week.

For the first year of the project, Tyler needs to come up with 30,000 cottonwood cuttings.  This spring, those cuttings will be put in the ground, and hopefully most will grow into new cottonwood trees.  Should be great.  First, however, we need to find 30,000 cottonwood cuttings!

It turns out it’s not difficult to get cuttings that can grow into trees.  You just need to cut 8-12″ sections from stems that grew during the previous growing season.  When those stems are put in the ground, the buds on the stems will facilitate the process of transforming them into new trees.  In order to get 30,000 cuttings, Tyler (with the help of others) has organized several volunteer workdays this month.  Last week, I joined other staff from The Nature Conservancy and the Arbor Day Foundation in a joint effort to collect as many cuttings as we could on a wet foggy winter morning.  The following photos are from that day.

It was a muddy ride out to collect cottonwood cuttings.

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Tyler found a site where a large number of young cottonwoods had grown where they weren't wanted. Tyler cut those trees down so our crews could come along and easily harvest the active growing tips of their branches.

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Matt Harris of the Arbor Day Foundation harvesting cottonwood cuttings.

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Cuttings were collected in buckets and hauled to a central collection point.

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A batch of cottonwood cuttings, counted, banded, and ready to store until they are planted in April. This tub contains several thousand potential new trees. The total count for the day's harvest was 12,500 cuttings.

The cuttings we harvested will be planted later this spring, and their success will be compared to the other methods of cottonwood establishment Tyler is testing.  The experience of others, and some pilot work we’ve done, shows that cuttings are a pretty dependable way to establish trees – so hopefully the majority of those 30,000 cuttings will turn into new trees.

Since much of my career has been spent removing trees (including a lot of cottonwoods) from prairies, this is a new experience for me.  I completely understand and agree with the logic and strategy of the project.  It’s just a little bit difficult to adjust my mindset.  So far, I’m doing fine.  We’ll see how I feel when we actually put the trees in the ground…

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Innovations and Inventions in Prairie Restoration

One of the great things about people who work on restoring (reconstructing) prairies is that they tend to be good at making things up as they go.  Some say prairie restoration is more art than science.  I actually think there’s plenty of science in restoration, but there’s no denying there’s a lot of art as well.  My favorite examples of restoration art are the fantastic machines and techniques people have come up with to harvest, clean, and plant prairie seeds. 

Prairie seed comes in all kinds of sizes and shapes.  That variety makes seeds fascinating to look at and study, but can create all kinds of issues for people trying to get those seeds from plant to the ground in order to make new prairies.  We’ve certainly had some humbling experiences here – including the comedy of errors that was our failed attempt to modify an old John Deere combine so that its augers would move fluffy prairie grass seed from the head to the hopper.  (We eventually sold the remains of the combine for scrap.)

Although our John Deer combine experience didn't work out so well, we've had better luck with our mobile grass seed dryer. This plywood box has a big electric fan hooked up to a 12" perforated pipe that runs along the bottom of the box. We haul the trailer out to the combine and load freshly-harvested seed into it. Then we back it into the shop and plug it in. The seed usually dries overnight. One side of the box then unbolts and makes it easy to unload. This was a team effort, designed by our staff and a local farmer - then built by a boy scout for his Eagle project.

Failures can be educational, but successes are even better.  I’ve been lucky to have some smart people to help me come up with ways to make our restoration work much more efficient and effective.  I’ve also had the opportunity to visit many other restoration sites around the U.S. and have been amazed at the variety of innovative and individual ways others have solved the challenges we all face. 

I learned the trick of burning the silks off of milkweed seeds from friends in Indiana. I've heard it might reduce germination - and we're testing that this year in the greenhouse - but I'm hoping if we spread them thinly enough before burning that it'll work. I hope so - it's fun! (Keep your face away from the heat)

I’d like to celebrate the innovative aspect of prairie restoration by highlighting some of the best tools and techniques that have been developed, but I need your help.  Over the next several weeks or so, I hope to gather up photos and descriptions of some of the unique, beautiful, and intricate ways people have addressed prairie restoration challenges.  Then I’ll put together a post (or maybe several) that showcases the best of what I find.  Hopefully, the result will be both useful and entertaining.

Please send me your favorite examples of tools, machines, and techniques that you’ve invented or modified in order to more effectively harvest, clean, or plant prairie seeds.  Failures and successes are both welcome – as long as they’re interesting.  Email 1-2 photos of each example, along with a paragraph or two of description to prairieinventions@yahoo.com.  Please keep photo file sizes under 2MB.  No guarantees, but I’ll try to use as many of your photos and descriptions as I can.