Maintenance Calendar

January

Inspect trees for defects such as decay, cankers, cracks or dead branches. Prune or remove hazardous trees.

Winter is time to prune trees. Train young shade trees to have a single trunk with strong, well spaced branches. On all trees remove branches that are dead, diseased, broken, cracked or rubbing on other branches.

February

Lawn sprinkler systems can cause irrigation overload. Over watering kills trees. Irrigation water is alkaline and trees prefer slightly acidic rainwater. Alkaline water can lead to iron chlorosis.

Processed urban wood waste makes good mulch for trees. Order truck loads of 5-100 cubic yards during winter for spring delivery.

March

Plan to finish winter pruning before the end of March.

Wash de-icing salt off trees in grates, medians, and other high-salt areas while the ground is still frozen.

April

Avoid pruning trees while leaves are forming. They are putting all their energy into leaf and wood production as they get ready for summer.

To prevent the spread of oak wilt disease, don't prune any oak tree in April, May or June.

May

Use lawn and garden chemicals with care. Shade trees, like dandelions, are broadleaf plants.

Look up before you plant trees. Choose a small maturing tree to plant under or near utility lines.

June

To reduce birch leaf miner damage keep birch roots cool and shaded. Use a four inch depth of woodchip mulch under the canopy of the tree.

Prune trees for clearance over streets and sidewalks and near signs. Many cities require 13 feet of clearance over streets and 8 feet over sidewalks.

July

Water Trees! Trees need at least one inch of rainfall each week May through July and a little less in August and September.

Choose a dry day to prune trees. Spores of some tree diseases spread during humid or damp summer weather.

August

Early fall color in a hard maple tree may be a symptom of girdling root syndrome. An affected tree has no root flare at the base.

Inspect young lindens and hard maples for stem girdling roots. If you can't see root flares at the base dig until you find them and make sure that none wrap around the trunk.

September

Remove stakes and ties from trees planted more than two months ago.

Avoid the mulch volcano! Before snow falls, pull mulch 6" away from the base of trees.

October

Wrap young trees with smooth bark to protect them from winter sunscald. Remove the wrapping in April.

Fertilize trees in autumn as leaves fall.

November

Inspect rodent guards on crabapple and other fruit bearing trees before the snow flies--be sure that mice cannot crawl in through the bottom.

Begin winter pruning once trees are completely dormant.

December

Contact an International Society of Arboriculture (ISA) Certified Arborist to schedule winter pruning. Check out the UMN Extension page for companies in Minnesota with Certified Arborists on staff. http://www.cnr.umn.edu/FR/extension/urbanforestry/arboristspage.htm

Dress up a special tree with holiday lights, but plan to remove them before the spring growing season gets underway.

 

This web page is maintained by Dave Hanson, dlhanson@umn.edu.
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