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Forest Connect: Free monthly woodland seminars

Just a quick note about an excellent source of free, high quality woodland info:

Forest Connect bannerCornell University’s Forest Connect series is the source for monthly live web-based seminars on a wide variety of woodland topics. The presentations are designed for woodland owners, and are typically offered at both noon and 7pm on the third Wednesday of each month. Even though the seminars tend to focus on eastern forests, many topics would be highly relevant to Minnesota woodland owners. And they’re completely free.

What have you got to lose? See a list of past presentations, or register to receive announcements of future events.

Have you attended one of these seminars? What was your take? Leave a comment below.

Community-based Forestry Survey

The US Endowment for Forestry and Communities is looking for information about community-based forestry. If you’re involved in this kind of work, I hope you’ll take a moment to fill in their survey.

What is community-based forestry? The overview document defines it as “the practice of developing locally appropriate, collaborative initiatives to create and sustain healthy working forests that generate value streams and benefits that support all members of healthy, forest-reliant communities.”

Does that sound like you or your group? If so, here’s more info on the survey, forwarded from the Endowment:

The U.S. Endowment for Forestry and Communities needs to know what you know about community-based forestry (CBF). They need to know what works and why.

Please click here to complete the survey.

Your information is essential and will help the Endowment identify opportunities to advance community-based forestry through their foundation grant-making program. In addition this information will provide many opportunities for funders and other interested organizations to advance the CBF field. Please encourage other CBF initiatives to take this survey as this information is vital for capturing all CBF activity on a national level.

Every organization that completes out this survey will be entered into a Participation Award drawing for $1000. The drawing will be on May 15, 2008.

The U.S. Endowment for Forestry and Communities (the Endowment) was established in 2006 to work collaboratively with partners in the public and private sectors to advance systemic, transformative and sustainable change for the health and vitality of the nation’s working forests and forest-reliant communities. As a first step, the Endowment has contracted with the Consortium for Community Forestry to compile information about CBF initiatives around the U.S.

Thank you on behalf of the U.S. Endowment for Forestry and Communities. Please click here to complete the survey.

Seasonal Care for Trees and Shrubs in Northern U.S. Climates

Welcome to the world of tree care! In the left hand column of the image below, you will find links to the many maintenance duties you can do to help keep your landscape trees healthy and safe. The accompanying chart highlights the most favorable timing for the listed tree care activities. Below this chart you can find links to other complete chart versions that are larger and easier to read.

Overall, periods of weather extremes (e.g., drought or high winds) should be avoided when planting, transplanting, fertilizing and pruning. The information available in this website provides a place to start for tree and shrub care, is not absolute for every situation, and is not intended to endorse any products or services.

Have fun!

SeasonalCare_22x28_seasonsSeasonalCare_plantSeasonalCare_transplantSeasonalCare_waterSeasonalCarefront_mulchSeasonalCare_evergreenBranchesSeasonalCare_evergreenShrubShearingSeasonalCare_deciduousBranchesSeasonalCare_stakingGuyingSeasonalCare_fertilizingSeasonalCare_stemProtectionSeasonalCare_branchesFoliageProtectionSeasonalCare_healthSeasonalCare_safetySeasonalCare_22x28_key

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Seasonal care for trees & shrubs: Safety

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Inspect your landscape trees and shrubs often- especially after storms.  After storms, hazard trees with loosely hanging branches or split trunks need to be removed as soon as possible to avoid any damage to buildings, people, and to other trees or shrubs.

At other times of the year keep a watchful eye for developing decay in trunks and roots, broken and hanging branches, dead branches or trees, an abnormally leaning tree, or anything that may indicate that a tree or part of it could fail and cause damage or injury.

Certified Arborists can offer advice on which plants should be removed, which ones can be saved, and if Plant Health Care (PHC) treatments are necessary.  Visit the International Society of Arboriculture (ISA) website to find a Certified Arborist nearest you.

For more information : How to Recognize Hazardous Defects in Trees and Hazard Tree Prevention

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Seasonal care for trees & shrubs: Health

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Keep a watchful eye for problems that may be developing on the plants in your landscape. Timely prevention is always more effective and economical than reacting to problems once they have developed.  Certain samples can be sent to your local Plant Disease Clinic (.pdf) for diagnosis.

For more information : Diagnosing Tree Health Problems (.pdf) and Forest and Shade Tree Health

If damages are observed and if Plant Health Care (PHC) treatments are necessary, contact a local Certified Arborist for an on-site diagnosis. Certified Arborist’s in your area can be found through the International Society of Arboriculture (ISA) search engine.

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Input needed: 5 things every woodland owner should know

Update: This story has now been published. Read it here: Five things every Minnesota Woodland Owner Needs to Know.

We’re working on a new story: Five things every woodland owner should know. The new content will be featured in the June email update and be a new featured page on MyMinnesotaWoods.org.

We need your help building the list!

For this story, you’re the expert. Imagine yourself talking over a cup of coffee with a friend who just bought wooded acreage for the first time. What would you tell her or him and why?

Leave a comment below with your thoughts. We’ll use your responses to build our June story.

Seasonal care of trees & shrubs: Stem and branch protection

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Stem Protection

The stems of landscape trees and shrubs may need protection from animals or mechanical equipment, especially during the winter months. Animal damage (feeding or rubbing) can be avoided by placing wire mesh or hardware cloth at least 3” from the stem. Mechanical damage (e.g. lawn mower or weed whip abrasion) can be avoided when a mulch ring (see mulch) or a plastic guard is in place. The plastic guard should only encase the portion of the lower stem that is most likely to be damaged by lawn equipment. As the tree grows the plastic guard will need to be removed and replaced in order to prevent girdling or stem constriction.

Branch and Foliage Protection


Ice and snow loading damage can be severe during cold, wet winters on multi-stemmed evergreen trees and shrubs (e.g. junipers, arborvitae, and yews). The overall form of the plant can be protected when the branches are secured with twine or burlap. Read page 3 of the below publication for more information. In order for the tree to resume normal growth remove the twine or burlap by spring.

For more information:  Protecting Trees and Shrubs from the Wicked Winters of the Upper Midwest (.pdf).

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Seasonal care of trees & shrubs: Fertilizing

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From an environmental quality and tree health perspective, all fertilizing of trees is recommended only in a case-by-case situation in the landscape. Fertilizing is not recommended unless nutrients are proven deficient in a soil sample tested by a laboratory or by a trained eye observing a deficiency in a plant’s foliage.

The recommendations in this chart refer only to nitrogen applications.  Before fertilizing your landscape with a complete fertilizer (nitrogen-phosphorus-potassium), contact a soil testing laboratory for a basic soil test [For MN only: U of MN Soil Testing Labratory]. A basic soil test will provide you with readings on organic matter, pH, cation exchange capacity, macronutrients and micronutrients (Smiley, 2003).  Soil testing laboratories may offer timing and quantity recommendations for complete fertilizers (N-P-K).

For information on selecting a soils lab for testing visit Guidelines for Choosing a Soil-Testing Labratory. Once criteria have been determined for selecting an appropriate soil lab, visit University Related Plant Disease and Soil Testing Services (.pdf) to find the lab nearest you.

Nitrogen needs are not usually highlighted on soils test.  Standard soil tests do not include total nitrogen readings since nitrogen is present in so many forms and is so mobile. According Dr. Kim Coder, adding (aka. “dumping”) too much nitrogen at one time can increase the plant’s susceptibility to insects and diseases, decrease drought tolerance, and can pollute waterways (1997).  It has been determined that high nitrogen use efficiency is achieved when trees are leafed out.

Application rate is critical: NEVER exceed package recommendations.  Do not apply on hot, dry and/or frozen soils.  Avoid nitrogen applications from leaf drop to bud break because uptake is minimal and pollution may occur.

For more information : Tree Nutrition Series: Nitrogen Perscription for Trees

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Seasonal care for trees & shrubs: Staking or guying

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Staking and guying of trees is rarely needed and is only necessary when the tree will not stand up on its own.  These practices may be necessary for 1-3 years while roots are growing and beginning to stabilize the tree.  Check attachment points on the stem every 3 to 6 months, loosen if necessary and remove within one year of placement.

For more information : Staking and Guying Trees: Best Materials and Techniques

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Seasonal care of trees & shrubs: Pruning deciduous branches

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How to prune trees is an excellent publication designed to illustrate the types of pruning that can be done, how pruning cuts are made, when to prune different plants, and more.

Shrubs:
Pruning cuts made to deciduous shrub branches are the same as pruning cuts made to all trees; however, types of pruning styles are special for deciduous shrubs.  How to properly prune deciduous shrubs (.pdf) highlights techniques of thinning, rejuvenation, shearing, pinching and deadheading. Shrubs to Behead details the strategy of rejuventation pruning along with species that respond best to this treatment.

Trees:
Waiting until the plant is dormant is the safest time to do any live-branch pruning.  However, unless the tree or shrub is susceptible to infectious disease (e.g., oak wilt, fire blight), removal of weak, diseased, crossing, rubbing, or dead limbs can be done throughout the year if needed.

The following table is grouped by infectious diseases and is a partial list of trees and shrubs that should NOT be pruned during the SPRING to EARLY FALL:

Northern species affected by oak wilt Species affected by fire blight
White oak (Quercus alba) Mt. Ash (Sorbus spp.)
Bur oak (Quercus macrocarpa) Cotoneaster (Cotoneaster spp.)
Swamp white oak  (Quercus bicolor) Hawthorne (Crataegus spp.)
Chinquapin oak (Quercus muehlenbergii) Quince (Cydonia sp.)
Northern red oak (Quercus rubra) Serviceberry (Amelanchier spp.)
Northern pin oak (Quercus ellipsoidalis) Firethorn (Pyracantha sp.)
Black oak (Quercus velutina) Spirea (Spiraea spp.)
Scarlet oak (Quercus coccinea) Pear (Pyrus spp.)
Chestnut oak (Quercus montana) Crabapple and apple (Malus spp.)
Blackjack oak (Quercus marilandica) Lilac (Syringa spp.)
Shumard oak (Quercus shumardii) Cherry (Prunus spp.)
Shingle oak (Quercus imbricaria) Apricot (Prunus spp.)
American chestnut (Castanea dentata) Chokecherry (Prunus spp.)
Tanbark oak (Lithocarpus densiflorus)
Southern species affected by oak wilt
Live oak (Quercus virginiana)
Scrub live oak (Quercus fusiformis)
Southern red oak (Quercus falcata)

Water oak (Quercus nigra)

Spanish oak (Quercus buckleyi)

For more information: How to Identify, Prevent, and Control Oak Wilt; Fireblight

Pruning of the following listed diseases and affected plants should not be done during WARM, WET periods of the year (i.e. spring).

Species affected by black Knot Species affected by cankers
Black cherry (Prunus serotina) Tree of heaven (Ailanthus altissima)
Common chokecherry (Prunus virginina) Hickory (Carya spp.)
Wild plum (Prunus americana) Dogwood, flowering (Cornus floria)
Holly, American (Ilex opaca)
Walnut (Juglans sp.)
Elm (Ulmus spp.)
Oak (Quercus spp.)
Persimmon, common (Diospyros virginiana)

Elm Trees: Elm pruning and Dutch elm disease (DED) management should be left to certified arborists.

A recommendation on when healthy (non-DED infected) elm trees should be pruned in order to decrease the chances of Dutch elm disease transmission through elm bark beetle flight is unclear. Some experts advise that pruning of healthy elm trees can be done at any time because the pruning wound does not attract beetles; however, other experts warns that healthy elms should be pruned only during the dormant season because the beetles are attracted to pruning wounds.

Sources of related information:

  • Byers, J.A., P. Svihra, and C.S. Koehler. 1980. Attraction of elm bark beetles to cut elm limbs on elm. J. Arbori. 6: 245-246.
  • Dreistadt, S.H., Dahlsten, D.L., and G.W. Frankie. 1990. Urban forests and insect ecology: Complex interactions among trees, insects, and people. BioScience 40(3): 192-198.
  • French, D.W., Ascerno, M.E., and W.C. Stienstra. 1980. The Dutch elm disease. U of MN, MN Ext. Ser. AG-BU-0518.
  • Haugen, L. 1998. How to identify and manage Dutch elm disease. USDA Forest Service NA-PR-07-98.
  • Landwehr, V., Phillipsen, W., and M. Ascerno. 1981. An integrated approach to managing native elm bark beetle populations in Minnesota. pp. 454-463. Proceedings of the Dutch elm disease symposium and workshop. Manitoba Department of Natural Resources, Canada.
  • Landwehr, V.R., Phillipsen, W.J., Ascerno, M.E., and R. Hatch. 1981. Attraction of the native elm bark beetle to American elm after the pruning of branches. J. of Econ. Ent. 74(5): 577-580.
  • Schomaker, M., Leatherman, D.A., and W.S. Cranshaw. Accessed 2006. Dutch elm disease. Co. State Univ. Coop. Ext. no. 5.506.

More information on seasonal care:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose: www.handeye.us

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

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QUIZ OF THE MONTH

This year, the US Capitol Christmas Tree will be cut from Minnesota's Chippewa National Forest. Which tree species has been selected the most to serve as the Capitol Tree?

Choose your answer here.