It’s time to rethink the idea of having one big shade tree

There is no denying the joy of getting out of the August sun by escaping to the cool shade of a mature shade tree.  Whether it is a maple or oak, there is no denying it’s benefit in the summer.

Not only does the shade they cast cool us, the trees actually cool the air around them. The air around a large shade tree is 2-9 degrees cooler in the summer than if the tree was not there.  This does not even consider that temperatures of surfaces can be 20-45 degrees F cooler than if they are not shaded.

Large shade trees also provide us with their display of color in the autumn.  Reds, yellows, purples, oranges light up our neighborhood in a parade of colors. Also don’t forget the childhood joy of jumping into piles of leaves.

Speaking of childhood joys, climbing trees is almost required for a happy childhood.  This pastime is probably the best recruitment aid the field of arboriculture has.  How many children get to say their dad climbs trees when asked what he does for a living?

These are all great reasons for planting a big shade tree.

Now, some reasons to not:

Sudden Oak Death, Emerald Ash Borer, Beech Bark Disease, Ramorum Disease, Dothistroma Needle Blight, Asian Longhorned Beetle, Pine Wilt, etc.

Perhaps the biggest reason to not plant that big shade tree is the one that has not YET been added to that list I just gave you.  That unknown disease or invasive insect that will threaten that tree you were thinking about planting.

Is he really telling me not to plant a big shade tree?

Yep.

Now let me explain.

If I dig out some of my business cards from say a decade or so ago, right after my name it said Risk Management Consultant.  What that meant was it was my job to reduce risk for the clients I worked with.  One of the strategies that I used was a really sophisticated concept I learned in a college risk management class.  It was “Don’t put all your eggs in one basket!”

Man can you believe I am you giving this sophisticated advice for free?

There WILL BE a disease or insect that will threaten the existence of that tree you were about to stick in the ground sometime in its lifetime.  There is no question about it.

So what will happen, when you notice that it’s June and your maple tree has not leafed out yet? You will panic, call an arborist, and find out you get to pay a whole bunch of money to have it cut down.  Then you will curse the nursery you bought it from as they told you it had no insect or disease problems when you bought it a decade or more ago.

So what should I do instead?

How about planting several smaller growing unrelated trees?

Don’t plant a Honey locust to shade your whole backyard.  Instead, plant multiple UNRELATED smaller growing trees to do the work of one big one.

By unrelated, I mean in different Genus, for instance maples (Acer) or oaks (Quercus).  If you look at a plant tag of the Sugar maple it will say Acer saccharum.  The Genus is the first word of the Latin name, in this case Acer.

So don’t plant three different Acer  (i.e. sugar maple, red maple, and Japanese maple) and think you have diversified your trees.  Insects and diseases often attack an entire family.  Think Emerald Ash borer.  It is just as happy killing a Green Ash as it is a White Ash.

One of the benefits of this approach is that you will actually get more shade in your yard QUICKER from a group of 3 medium sized growing trees than you would from one tree that will eventually get real big.

You can also get other benefits from a variety of trees over one tree.

Let’s look at an example:

Option #1 – Pick one large growing shade tree

Lets choose a red maple (Acer rubrum) – This is one of the most commonly planted shade tree these days in my area.  It has an upright, spreading form and can get 60 feet tall.  Fall color varies from yellow to scarlet, but is usually good.

Option #2 – Pick three smaller unrelated trees to provide the shade of one

Allegheny serviceberry (Amelanchier laevis) which gets 15-25’; fall color is orange red; it gives a sweet and edible purple fruit that attracts birds.

Ironwood (Carpinus caroliniana) which gets 20-30’; fall color is orange-scarlet; bark is fluted which gives it a muscle like appearance.

American Yellowwood (Cladrastis lutea) gets 30-50′ feet tall; fall color is yellow; foot-long wisteria-like clusters of fragrant white flowers appear in early summer, often in alternate years.

Some of the DOWNSIDES of choice #2

• Possibly higher cost from buying several trees (although this may not be the case)
• More likely to have at least one of these trees have insect or disease issues (since there are more trees)
• Harder to shade the roof of the home with shorter trees (although proper siting of the largest growing of this group, Yellowwood could overcome this problem on single story houses)

Some of the BENEFITS of choice #2

• More shade immediately
• Different fall colors of leaves turning at different times thus extending fall season
• Attractive flowers from serviceberry and yellow wood
• Bird attracting fruit from the serviceberry
• Winter interest bark from the musclewood
• Less susceptible to one disease causing you to loss all your shade

Next post, I will give a list of some recommended smaller “shade trees” to use besides the three excellent ones above.  Subscribe to my posts via email to be sure not to miss it.  Your e-mail will never be shared with anyone, just scroll up to the top of this page enter your email in the box at the right.

PS If you have a big property, go ahead and plant a lot of unrelated BIG shade trees if you want.  You have room.  Most of us with our 1/4 acre lots don’t.