One of the sure signs of autumn is fall foliage in the landscape as woody plants prepare for winter.  Here are some things that can be done to help prepare your trees for the long season ahead:

1. PLANT.  Yes, fall is a great time to plant trees.  Cooler temperatures enable plants to acclimate to a new home without the stress of high air and soil temperatures.  While selection at nurseries may be limited, trees are often on sale in the fall.  Make choices that are suitable for North Dakota’s alkaline soils – don’t buy something just because it sounds like a good deal.  Trees are a great investment!  For winter interest, choose a tree with interesting bark or fruit that hangs on the tree beyond fall.
2. DON’T FERTILIZE newly planted trees, and only apply slow-release fertilizers on established trees.  Applications of nitrogen will encourage new tree growth which won’t have a chance to harden off before winter.  If you’re fertilizing your lawn, you’re also fertilizing any trees nearby.   Trees have a root spread equal to or greater than the height of the tree.
3. WRAP newly planted trees with brown kraft paper, starting at ground level and working your way up the tree to the first branch.   White plastic tubing can also be used.  This protects young trees from winter sunscald on the southwest exposure of the trunk, and will also deter rodents from feeding on the bark.  Trees most susceptible include fruit trees, mountainash, honeylocust, maples and linden.  Tree wraps should be removed in the spring.
   
   
   Applying paper tree wrap before winter.  Photo from Lowe's website.
   
   
4. WATER trees before freeze-up.  Tree roots remain active until soil temperatures dip below 40 degrees.  Watering is especially beneficial for evergreens, which transpire tiny amounts of moisture through their needles throughout the winter months. 
5. HERBICIDE APPLICATIONS should be done with caution around trees.  In last week’s Center Points on Fall Lawn Weed Control, Kathy mentioned that herbicides are most effective on lawns in the fall, but also stated that some herbicides can be detrimental to tree roots, especially with repeat applications.  Spot spray, if possible.  Learn to tolerate a few weeds.
6. PRUNING is best done when trees are dormant, so leave that task until early spring.  Routine pruning in early spring before buds swell enables the tree to naturally seal off pruning wounds most effectively.  Broken branches should be properly pruned as soon as they are noticed.  Don’t use pruning sealer, tar or paint on any tree cuts or wounds.  A proper pruning cut doesn’t require sealer, and no amount of sealer can fix a bad pruning cut. 
7. FIREWOOD.  For those who burn wood, fall is a popular time to harvest and cut firewood, or purchase it from a seller.  Keep invasive pests away by purchasing or harvesting firewood locally.  Transport of infested firewood is most likely how emerald ash borer will make its way to North Dakota.  Don’t move firewood.  Protect North Dakota’s trees!

• Links for tips on planting, pruning, and maintaining trees:

http://treesaregood.org/treeowner/treeownerinformation.aspx

• Information on NDSU Woody Plant Improvement program and NDSU releases:

https://www.ag.ndsu.edu/plantsciences/research/woody-plants

Fall foliage on Ohio buckeye at CREC. Photo by Gerri Makay.

Gerri Makay
ND Forest Service
Community Forestry Program Manager
Gerri's office is located at the CREC.