Time to Plant Some Oaks!

Chuck Chambers measures a big white oak at Englewood MetroPark

Oaks as a group are a very important part of our mature forests.  MetroParks cover map data reveal that oaks as a group make up 25% of the canopy of our mature forests, the largest component.  They are long-lived, slow growing, commercially valuable, produce big crops of food for wildlife, and most are drought and fire resistant.  Oaks are shade intolerant.  This means that they have to have sunlight and cannot grow in the shade of other trees.  Acorns and young oaks are designed to colonize open areas where they can get the sunlight they need.  Around here we have eight species: northern red (Quercus rubra), chinquapin (Q. muhlenbergii), bur (Q. macrocarpa),  Shumard (Q.shumardii), white (Q. alba), swamp white (Q. bicolor), shingle (Q. imbricaria), and black (Q. nigra).

Strangely though, its pretty difficult to find a young oak out there.  The big ones in the woods still produce big crops of fall acorns, but almost none of these seeds become a tree.  This phenomenon and problem is not unique to southwest Ohio, it is happening all over the eastern and midwestern United States.  It seems we are destined to lose some our most valuable and important forest trees.  This chart shows the components of young forests in MetroParks, note the lack of oak.

What is happening to oaks?  The three main things that are preventing oak reproduction around here are:

Dull Woods Conservation Area:
 A very nice fragment.

1. Fragmentation-  Acorns are spread mostly by squirrels and blue jays.   Squirrels carry acorns a short distance and bury them individually for snacking later.  Fortunately for oaks the squirrel's memory must not be that great and some acorns are forgotten.  If they were buried in an open area they have a chance to grow into a mature tree.  Because of this, oaks seeds don't disperse very far from the parent tree.   Unfortunately for oaks, our local forests have been reduced to small patches and isolated woodlots.  Therefore, only a fraction of the landscape, the part that is near an existing mature oak, is open to oak colonization.


2. Too Many Deer-  White-tailed deer love to eat acorns, and they especially like oak seedlings.  Any oak that does manage to take root in a good spot is likely going to be eaten by a deer.  Oaks and deer have always had to co-exist, but with densities these days of over 50 animals per square mile, oaks don't have a chance.

3. Lack of Fire-  Oaks have evolved such that trees and their seedlings are resistant to fire.  Prior to about 1930 fire was a common occurrence in many of the forests of the United States.  In the eastern United States the Native Americans, pioneers, and early settlers commonly used fire to create and maintain open landscapes and forests.  Fires around here were not the big crown fires that we see on television out west.  They were low ground fires that burned up the leaves and sticks.  They also burned up the seedlings of most trees.  But oaks had an edge, they could withstand this, and their reproduction was good.  Nearly all of the large oaks that we still see today likely had their start after one of these fires.  Smokey the Bear was very effective though, and fire is no longer part of woodland management around here.  As a result, seeds of other trees such as black cherry, locust, and sugar maple are the ones that get a start.

How can we help oaks?  In more forested parts of Ohio the most common method is clearcut logging.  Openings are created in existing forests containing oak by removing all the trees in a small area.  Acorns and existing young oaks are then free to grow in the sun and make a new oak forest.  This works especially well in hilly, wooded southeastern Ohio.

Young Oaks Thriving Thanks to Tree Shelters

 Around here we don't have much forest land, and clear cutting what we do have would not be a good idea.  What we can do is plant oaks into old fields and other open areas where it would be good to have them.  If a young oak can get above the competition and browsing deer it will do fine.  In fact, given the drier weather we have been having it makes even more sense to plant oaks.  I'd recommend figuring 4 dollars per oak seedling though.  Good bare root seedlings can be purchased for about a dollar a tree, but you'll also need a tree shelter and stake to protect it for the first several years.

If you want to volunteer to help grow and plant oaks on the MetroParks go to
www.metroparks.org/forests
 and sign up!