Sunday, February 16, 2014

Girdling Roots

With all this snow, ice, and very low temperatures we have been experiencing this winter, it is hard to imagine that spring will ever come.

Don't worry. It will.

And when milder weather approaches, gardeners will flock to the nurseries like people rushing to the grocery store to buy milk and bread before a snow storm, buying anything and everything that is in bloom at that time.

There is nothing wrong with that.  After a long winter's slumber, there is nothing better than getting out there and planting a few new shrubs and trees that we have been thinking about, or simply catch our eye.

But one word of caution here:  be a careful consumer.

The nurseries know that they will face an onslaught of customers as soon as spring hits.  They will have everything with flowers on it out for sale.  In their rush to market their plants, some not-so-good specimens will make the cut and get put out for sale.  I know this because I see it, and also because I used to work at a nursery where they grew their own trees and shrubs, dug them themselves, and sold them.  I would see a sub-par specimen, and question it.  "Don't worry...it will sell. If it is blooming, it will sell."

True enough, but what happens later?  In that example I am referring to, the problem was co-dominant stems, which I will discuss in a later post, but there is another huge problem in the industry, Stem Girdling Roots.

In container grown trees and shrubs, the roots grow outward, then hit the container wall.  There is nowhere else to go but around.  And around. And around.  And when the nursery decides to step up the pot from a one gallon to a three gallon, they usually will not break up the circling roots and just throw soil around the root ball.

These circling roots then get hidden from view.  If you pop out that three gallon rootball, you will probably see soil with fine roots throughout, and not the circling mess underneath.  And then it goes to a five gallon, seven gallon, 15 gallon, etc.

Eventually, those circling roots will grow around the trunk of the tree, cutting off the circulation throughout.

You can also get a girdling root situation if you pile mulch up around the tree and shrub trunks.  The tree will put roots out into the mulch, and these roots will grow over top of the existing roots, eventually cutting off their circulation.  You all have seen this at shopping centers and malls.  Just look for the "mulch volcano" trees with gaps up and down the line to see what the long term effects are.

Here is an example:



I bought this red bud from my local nursery as part of a lot for a clients yard.  This was part of a larger delivery.  If I had selected the plants myself, this one would have stayed at the nursery.  See that root going around the trunk?  Imagine when the trunk and root have grown for 10 more years?  Problem.  I decided to have a look further.




You can see the root wrapping around the trunk, but there is also a good sized root that has been growing down the sides of the container.  That is not necessarily very bad, but should be addressed also.



Here I have cut the stem girdling root off at the trunk, and also cut off the downward growing portion of that larger root.  Problem solved.  This would have been better off rejected, but these issues can be dealt with.

The problem is that these issues would not make themselves apparent for 10-15 years.  At that point there is really nothing that can be done.

So when you looking for plants, a little inspection goes a long way.  I also recommend washing the soil off of the containerized root balls.  Rough them up.  Do anything you can to inspect the roots.  Do not just pop them in the ground out of the pot.  You will do yourself and the plant a great deal of good.