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Emerald ash borer: Learning from the Michigan experience

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Tuesday, May 17, 2016, noon – 1:00 p.m.

With recent discoveries of emerald ash borer in and near Minnesota’s northwoods, foresters are getting more serious about options as we face potential widespread ash mortality. Forest health specialist Bob Heyd has seen this loss first hand in Michigan and Andrew Arends will discuss EAB preparations and plans within the Minnesota Department of Natural Resources.

Speakers: Bob Heyd, Michigan DNR and Andrew Arends, Minnesota DNR-Forestry

Registration: Register here to watch online or attend one of the broadcast site locations for free.

Help create the Minnesota Bee Atlas

Creative Commons image courtesy of Flickr user Brett Whaley

We all know how vitally important pollinating insects like bees are to our ecosystem and food chain. But did you know that as a forest landowner in Minnesota there are opportunities to help pollinators thrive? In addition to making important stewardship decisions to help bees on your land, now there is a program for Minnesotans to help researchers track the hundreds of wild bee species that live in our state.

The last time a survey of Minnesota bees was completed was in 1919 when only 67 species were listed. Scientists suspect that there may be closer to 400 species but we need the help of citizens like you to find them all. Funded by the Environmental and Natural Resources Trust Fund, the Minnesota Bee Atlas will combine information from the University of Minnesota Insect Collection, Minnesota DNR, and other sources to create a publicly accessible database of wild bees in Minnesota. The information we gather on species distribution and diversity will be important to help track if or how bee populations are changing and how those changes might affect land management decisions.

Volunteers may participate in several different ways depending on interest and desired time commitment. Opportunities include submitting photos of bees, identifying bumble bees on an assigned transect route, monitoring a nesting block, and creating backyard bee habitat and reporting observations. More information about each of these opportunities can be found at

Creative Commons image courtesy of Flickr user Brett Whaley.

April 2016 webinar: Climate Change and Eastern Larch Beetle

Tuesday, April 19, 2016, noon – 1:00 p.m.

The eastern larch beetle is found throughout North American tamarack forests. However, its tree-killing behavior in Minnesota and Wisconsin hasn’t followed typical patterns in recent decades.  In this webinar we’ll examine the causes of an ongoing outbreak that has shown no signs of slowing down.

Speaker: Brian Aukema, UMN Department of Entomology

Registration: Register here to watch online or attend one of the broadcast site locations for free.

Update: Watch the webinar below.

Gathering Partners of Natural Resources Conference

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Have you made plans to join us at the 2016 Gathering Partners of Natural Resources conference? This year’s theme is Nurturing a Healthy Big Woods Big Rivers Biome, and we are meeting in beautiful Winona, Minnesota! There are dozens of amazing sessions to choose from, where you can learn about woodland management, tree ID, invasive pests, wildlife, and more.

Conference Schedule

Friday, May 20
Day 1 features pre-conference full and half-day field trips, concurrent sessions, and an MFA membership meeting. The conference kicks off with a welcome address and dinner beginning at 6:30 pm, followed by the keynote by Karen Oberhauser.

Saturday, May 21
Take an early morning guided walk, and then meet us for breakfast at 7:00 am. Elect to take a half-day field trip or join a couple of on-site sessions. A picnic lunch will be followed by an afternoon of more field trips and sessions. A cash bar and hors d’oeuvres will be open until the evening banquet and awards ceremony begins–make sure you stick around for the Tree Farm awards! End the night with one of our planned social activities, including a movie, games, bonfire, cash bar and dessert bar.

Sunday, May 22
Early morning walks and breakfast will be followed by another set of learning sessions. At noon, we will have lunch and listen to closing remarks. Then it’s goodbye until next year!

Who can attend?

Woodland owners, Master Naturalist volunteers and instructors, citizens interested in nature and the environment, senior citizens, young adults, teachers, retired professionals and more! This conference is for anyone with an interest in environmental stewardship and the great outdoors.


Dorm lodging is available at Saint Mary’s University for a small fee. You are not required to lodge on campus. A listing of motels, bed & breakfasts, and campgrounds can be found at Visit Winona.

More information

Get information on the conference agenda, sessions, field trip descriptions and more at the Gathering Partners of Natural Resources conference website. We’re looking forward to seeing you in May!

Master Woodland Owner Program

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We are proud to announce that the Master Woodland Owner program is here!

Have you ever wondered:

  • What are my hopes and dreams for my woods?
  • How many trees are on my property and what species do I have?
  • How healthy are my woods?
  • How do wildlife species depend on my woods?
  • How are my woods changing?


In our cohort-driven educational program, you will learn from experts and other forest landowners about implementing sustainable forest management practices that improve the health, productivity, and resilience of your woods.

Any woodland owner and their family members responsible for managing woodlands in Minnesota or the Upper Midwest region is eligible to register. There is no minimum or maximum acreage requirement.

After completing the Master Woodland Owner program, participants will be able to:

  • Consider the different reasons and ways to manage their woods
  • Identify common trees and invasive plants
  • Map their property and conduct a woodland inventory
  • Find and talk with natural resources professionals
  • Select appropriate trees and know how to plant them
  • Develop and refine goals for their property
  • Discuss financial considerations of land ownership (including tax incentives and estate planning) with their family and financial/tax advisors


We’ve created a new website for the program where people can learn more and register, and students can log in to access course content. Check out to see if the Master Woodland Owner program is right for you!

Read the March 2016 update now

Click here to read the March update. This month’s features include:

  • Webinar: forest management effects on water
  • Pruning trees
  • Emerald ash borer in Wabasha County
  • Become a Minnesota Tree Inspector
  • Eastern bluebird
  • It’s maple syrup season!
  • Become a Minnesota Master Woodland Owner
  • News, upcoming events, and more.


March 2016 update


Pruning: What, Why, When, and How

by Eric North, Research Fellow, University of Minnesota Department of Forest Resources


What is pruning?

One of the most frequent questions I am asked with regard to tree care is: “When should I prune my tree?” While I think people are actually asking what time of year they should prune their tree, it might be better to start with the question, “What is pruning?” Pruning is wounding!

Does that mean that pruning is bad for trees? It depends. When done well, pruning can improve the health and form of trees. When done poorly pruning can reduce tree health and create dangerous situations. When following proper pruning techniques developed with tree biology in mind, pruning can aid in the development of tree form and structure. Unlike people, trees do not heal; at least not in the same sense as people heal. When a healthy person cuts his or her finger, the human body responds by replacing the damaged cells with new cells that serve the same function. When a tree is cut, the damaged tissue is not replaced. The damaged tissue remains and is “walled off” from inside the tree in a process known as compartmentalization. Compartmentalization is the chemical and physical process by which trees form a protective barrier between the damaged tissues and existing or new tissues. Anyone who has seen a knot in a piece of wood has seen the results of compartmentalization. The knot is an old branch that new tissue (i.e. wood) has grown around before the tree was cut-down. Instead of healing, trees grow new wood around wounds, but the wound remains.

Did you know? Minnesota’s state tree, the red pine, will self-prune if branches become too shaded to contribute to the process of photosynthesis. The self-pruning adaptation in red pines is an example where natural pruning appears to benefit the tree through conservation of resources. Even though pruning creates a wound, there can be a benefit to the overall structure and health of a tree.

Why prune?

In the pruning guide book The ABCs Field Guide to Young and Small Tree Pruning by Andrew G. Pleninger and Christopher J. Luley, Ph.D., the authors outline a simple approach to tree pruning. Unlike the many great resources on how to prune, which often start with the proper tools and move directly into making your first cuts, Pleninger and Luley start with “Assess the Tree.” Assessing the tree helps to answer the question of why are you pruning. Sometimes pruning is done to raise the canopy by removing the lower branches, so that mowing or gardening is easier. Sometimes tree branches break in a storm and need to be removed for safety reasons, pruning to increase flower or fruit production, or to reduce disease. First ask why you are a pruning, what is the end objective? Knowing your objective is the first and very important step to consider before cutting branches. Create a plan of which branches to remove and remove the smallest amount to accomplish your objective.

When to prune?

What time of year is the best time to prune? There are several things to consider when deciding what time of year to prune your tree. Here are some general guidelines to consider for planning when to prune:

  1. Know the species and associated diseases or pest.

In Minnesota, oaks are negatively affected by the fungal disease known as oak wilt. The fungus is spread overland by oak bark beetles. The beetles are attracted to freshly cut oak trees. The timing of oak pruning should be carefully considered to avoid pruning when the beetles are actively flying. Knowing the diseases and insects associated with a tree species is an important step in selecting an appropriate time to prune.

  1. Flowers and fruit

Generally if the tree or shrub produces spring flowers (think lilacs) the buds differentiation into flower or vegetative growth on twigs that are one year old. This means that if you want flowers, you should prune immediately after flowering. If you wait until the new buds have formed you will likely prune off the buds for next year’s flowers. Another great reason to know your pruning objective and a little about the tree species before you start pruning.

  1. Safety pruning

If you are pruning to remove broken or dead branches then pruning should occur as soon as can be done safely. If you need to prune an oak for safety reasons during a high risk period for oak wilt, a clear coat of Shellac can be used to cover the wound immediately after making the cut to reduce the risk of attracting oak bark beetles. In the case of urban trees, safety is often a primary concern and should be addressed as quickly as possible.

  1. Watch out for stressful conditions

Yes, trees can be stressed. Remember even when properly done, pruning is wounding and a tree’s ability to respond to a wound is better if the tree is not stressed. Potentially stressful conditions are: drought, newly planted trees, recently injured trees (e.g. storms, lawnmowers, etc.), or root disturbance to name a few. Pruning a tree that is already stressed can make matters worse. If the trees needs to be pruned, consider managing the stress (e.g. in droughts, water your tree).

How to prune

The basics of how to prune can be found in several great books and online resources. Two excellent free resources are available online: How to Prune Trees – US Forest Service and Tree Owner’s Manual. The basics are to make the smallest cut possible, cut only the branch to be removed (not the trunk or other main branch), use the proper tools safely, and if you need to get off the ground it’s probably time to hire a certified arborist.



Eastern Bluebird: Happiness on Wings


Eastern Bluebird. Flickr photo courtesy of Kelly Colgan Azar.

Eastern bluebirds are a symbol of summer happiness and likely one of Minnesotans’ most beloved birds, up there with chickadees and loons. When enjoying a spring or summer day on our hobby farm, I can’t help but pause to take in this small thrush’s sweet, warbling song and brilliant colors. They have been cheerful company on many days of garden, horse and chicken chores.

A Recovery Success Story
While eastern bluebirds are currently common due to the proliferation of nest boxes and bluebird trails, that hasn’t always been the case. They declined dramatically from the 1930s to the 1960s due to loss of habitat and nest site competition from house sparrows and European starlings, two non-native birds and bluebird enemies. Together, partners like the DNR Nongame Wildlife Program and Bluebird Recovery Program sponsored workshops, published education materials and promoted bluebird houses. Restoration efforts paid off. Minnesota now has one of the most successful bluebird recovery projects in the nation.

Not Really Blue
Eastern bluebirds have big, rounded heads, large eyes, plump bodies, and alert posture. Their wings are long, tail and legs fairly short, and bill short and straight. Males are a vivid, deep blue above and rusty or brick-red on the throat and breast. Females are grayish above with bluish wings and tail, and a subdued orange-brown breast. And guess what? They aren’t really blue, but gray. Their feathers bend light so they look blue. When light enters their feathers, it bounces off tiny air pockets and cells so that only the blue wavelengths reach our eyes.

Habitat Mix
Bluebirds prefer habitat of mixed hardwood forest and grassland with short, sparse, mowed or grazed vegetation. Perches such as scattered trees, powerlines or fences are important. They inhabit open woodlands, meadows, old fields, roadsides, pastures, hay lands, prairies, orchards, golf courses, backyards or city parks of every county in Minnesota.

Bugs and Berries
Bluebirds are ground foragers, primarily catching insects caught on the ground much of the year. Major prey include caterpillars, beetles crickets, grasshoppers, and spiders. They typically hunt by sitting alertly in the open on a perch and scanning the ground. They drop to the ground after insects with fluttering wings, followed by a quick return to the perch. Occasionally, they catch insects in midair. They can sight their tiny prey from 60 feet or more away. In fall and winter, bluebirds eat large amounts of fruit such mistletoe, sumac, blueberries, dogwood berries, hackberries, and juniper berries.


Eastern bluebird feasting on berries. Flickr photo courtesy of Kelly Colgan Azar.

Bluebird Tweets
Bluebird language is diverse. Their song is a fairly low-pitched warble of several phrases. Typically, unpaired males sing this song from a high perch or sometimes in flight to attract a mate. Their most common call is a soft, short, low-pitched tu-a-wee with a querulous tone. Bluebirds use it in all seasons to stay in touch or signal to nestlings that food is on its way. When bluebirds get too close to each other, they let out a single, harsh screech. If nervous at the approach of a ground predator, a loud, continual chit-chit-chit is uttered. And when attacking predators or other intruders, bluebirds may dive-bomb them and clack their bills.

Devoted Parents
Some bluebirds winter in Minnesota, but most migrate south, returning in March. They nest April to July, typically raising two broods. They depend on cavities excavated by other wildlife, such as woodpeckers, or nest boxes. The male fights feistily over and defend about five acre territories. He displays at his nest cavity to attract a female, bringing nest material to the hole, going in and out, and waving his wings while perched above it. The female builds the nest by loosely weaving together grasses or pine needles, lining it with fine grasses and occasionally horse hair or feathers. The eggs, usually five to six, are pale blue, or rarely white, and incubated 13-16 days by the female. After a nestling period of 18-19 days, the young take flight. Bluebirds typically live two-three years, five if lucky. The oldest recorded eastern bluebird was over 10 years old. Birds of prey, snakes, and various mammals, especially cats and raccoons, are their main predators.

Keeping Bluebirds Common
How can you help ensure this cheerful bird remains common?

  1. Keep open habitats healthy. Encourage a diversity of native grasses, forbs and fruit-bearing shrubs that will provide insects and fruit, and periodic disturbance such as haying, mowing, grazing or prescribed burning. This management will also benefit monarchs and pollinators such as bees.
  2. Keep cats indoors or on a leash, as noted in the 2015 February-March Creature Feature.
  3. Reduce or eliminate use of chemicals that may negatively affect bluebirds and their food.
  4. Buy or build nest boxes carefully designed with entry holes and dimensions that meet bluebird needs. See the Peterson plan in Woodworking for Wildlife for a tried and true design. This useful book is available from Minnesota’s Bookstore on line.
  5. Properly place and maintain nest boxes.
    1. Choose locations in open habitat with short vegetation, with nearby perching sites, at least 300 feet from brush, and on high ground.
    2. Call 811 before sinking posts to have the site checked for underground utilities. Use predator guards to eliminate climbing predators or ½ inch metal electrical conduit over ½ inch rebar. Entrance holes should be five to six feet above the ground and face east or northeast.
    3. Do not overload an area with nest boxes. Space them at least 100 yards apart.
      Allow nest box use by native birds such as chickadees and tree swallows. To accommodate tree swallows that are competing with bluebirds, pair two nest boxes about 20 feet apart.
    4. Avoid placing boxes where house sparrows are abundant. Remove house sparrow nests and eggs.
    5. Avoid brushy areas where house wrens are likely to reside. They poke holes in other birds’ eggs, carry out nestlings and take over nest boxes by filling them with sticks.
    6. Check nest boxes at least once a week during the nesting season until nestlings are 12 days old to identify and address problems such as blowfly infestations or house sparrow nests. After that, monitor only from a distance to prevent chicks from jumping or flying prematurely. Remove old nests as soon as the brood has flown.
  6. Establish and maintain a bluebird trail of five or more nest boxes where they can be easily checked.
  7. Consider recording nesting data with NestWatch, a nationwide monitoring program to track status and trends in the reproductive biology of birds.
  8. Join the Bluebird Recovery Program. Founded 1979, it was the first state bluebird organization in the nation. Enjoy its next annual Bluebird Expo on April 16 in Byron.
  9. Learn even more from the North American Bluebird Society.
Eastern bluebird approaches a Peterson  type nest box.

Eastern bluebird approaches a Peterson type nest box.

March 2016 webinar: Forest management effects on water


Tuesday, March 15, 2016, noon – 1:00 p.m.

Forest management operations can impact soil water balance and hydrology indirectly through altered transpiration or directly through compaction and associated changes in soil properties. Dr. Karwan will review the common drivers of soil hydrology changes following forest operations, compare effects in conifer- vs. deciduous-dominated stands, and suggest practices to reduce negative impacts in the long term.

Speaker: Diana Karwan, UMN Department of Forest Resources

Registration: Register here to watch online or attend one of five broadcast site locations for free throughout Minnesota.

Watch the recording here:


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