Know thy woods: On the value of monitoring

You may have noticed a lot of talk on MyMinnesotaWoods about forest health and phenology. There’s a common theme and a good reason for this: There are a lot of good reasons to monitor your woods through the weeks, months, years, and even decades:

Crown competition in a northern Minnesota pine stand. Click for a better view.

1. Trees and woodland stands are constantly changing. Trees have to grow to live, and big trees take more room than small. Constant competition for growing space means that some trees will win and some will lose. Depending on how variable your land is in terms of slopes, soils, and species, the competitive struggle may play out differently across it. The more you know about which species grow best where on your land, the better you’ll be able to plan for the future of your woods.

2. Invasive species are moving in. Garlic mustard, emerald ash borer, and a number of other invasives are establishing themselves throughout Minnesota’s woods. New species are arriving every year. Once these species are well established on a site, it can take a tremendous amount of work to eradicate them. The more quickly we notice when these species have arrived, the more likely we are to succeed at controlling them. Minnesota Forest Pest First Detector volunteers are an important part of this strategy, but the more informed eyes and ears across the landscape, the better our chances to reduce eradication costs and maintain woodland health and productivity.

Red maple on the north shore. Photo by Lee Frelich. Click to read the 2009 CURA reporter article.

3. New native species are moving in too. Every 30 years, the National Oceanic and Atmospheric Administration calculates new “normal” temperature and precipitation levels based on data over the past 30 years. Minnesota’s new normals, calculated for the period 1980-2010, show a January average temperature that’s 2.5 degrees F higher, warmer nights in both summer and winter, and higher precipitation than the 1970-2000 normals. These changes have begun, and will continue to affect how and where trees grow. In the coming decades, the ranges of many native Minnesota trees will continue to shift toward the north and east.  The sooner we notice these changes on our land and begin to plan for them, the healthier and more productive our woods will be.

4. To engage kids and family. Noticing when trees or flowers start to bloom, when leaves appear in spring, when acorns start to drop, the first frost of the fall and the last of the spring is easy; it just takes attention and a pencil. This kind of monitoring is a great way to help your kids or grandkids develop not only observation skills, but an appreciation for nature and your land. Why is this important?  Many woodland owning families find themselves wondering about the future of their land.  With declining hunting participation among younger generations, increasing attention to digital screens and less time outside, actively cultivating a fascination and deep connection with nature gives us hope for the future of such a big part of Minnesota’s culture and history: Wise use and sound management of our unparallelled natural resources.

Thinned red oak near Mora, MN. Click for a better view.

5. To inform your woodland care and management activities. The best land management involves first understanding what’s happening naturally on your land, then working with those natural forces to lead woodland stand development to match your goals for the land. Those goals might involve growing big trees faster, supplying a local renewable resource to the market, attracting diverse wildlife, or simply maintaining a safe and healthy woodland for the next generations of your family to enjoy. The more carefully you observe the natural changes on your land, the better you can work with them to achieve your own goals.

6.  To protect your investment.  Minnesota’s “new normals” will change the population dynamics of some native as well as non-native woodland insects and pathogens by both reducing winter pest mortality and weakening and stressing trees adapted to different conditions. Informing yourself about Minnesota forest insect and diseases, then paying attention and quickly detecting and controlling pest outbreaks will not only keep your woods healthier, they’ll reduce your costs and protect your investments, financial and otherwise, in the future of your woods.

We’ll be writing more about monitoring on MyMinnesotaWoods in the coming months. How do you monitor your woods? What do you look for and why?

Eli ‘s work addresses Minnesota forest ecology & management. He’s based in St Paul.

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  1. I have been frantically scouting for adult Garlic Mustard plants to prevent them from going to seed lately. We had a several acre infestation through out 25 acre woods. I go out with a gardening tool and a handful of white flags. It is pretty discouraging, but I did find only 35 adults last Sunday in 2 hours. Last year I missed about 6 plants that went to seed. I balance the time with some fun activity such as planning the release of some nice trees, digging small Buckthorn, and admiring the results of past work. Monitor your woods!

    1. Thanks John for the comment! I think you’re the poster child for monitoring–your work to identify and eradicate invasives on your property speaks volumes on the value of not only careful monitoring but commitment and action to get rid of problem species. For those unfamiliar with John’s work, here’s a short video that we made together on garlic mustard control, shot on his Delano property a few years back: Garlic Mustard: A Minnesota woodland owner’s story.

  2. We have 12 acres on the South Branch of the Root River about 7 miles SE of Spring Valley, MN. I have been working hard for the last 3 years spraying Garlic Mustard on the road and also at the end of our driveway. I think it came in with the snow plows that first year, I thought I was pretty successful until 2 weeks ago when I found ALOT of it along our creekbed where it empties into the SB and all along the river banks. We flooded 2 years ago and it must of come thru then. I’m totally deflated, there is no way to control this massive amount now. I walked into the adjoining lands and its there now too. Any ideas? Should I contact anyone? I’m a Master Gardener in Fillmore County and brought it up at our last meeting but no one else had seen it yet.
    Thanks, Shelly Skindelien 🙁

  3. oh yeah, I forgot, we have plenty of Buckthorn we have been dealing with but when I talk to our township supervisors about taking care of the Buckthorn full ditches, their comment was: “In my experience, I have found that nature has a way of taking care of itself.” That comment was stated after he asked me what buckthorn was and I had explained it to him..
    Thanks again, Shelly