Seattle Chainsaw Massacre

In the spirit of the season I’m including some photos from our neighbor’s willow tree that failed a few years ago.  The failure wasn’t unexpected, given the age of the tree and the lack of crown care it received.  What’s truly scary is the “tree service” that came out to deal with the problem.  Low bid wins again!

(And yes, I’ll post a puzzler as well.  Two for one today!)

Here’s the willow after the crown collapsed

Rickety ladder + chainsaw = suspense!

Standing in the collapsed crown – no rope or other safety equipment

 

Look Ma!  One hand!!!

And best (worst?) of all, the remaining trunk was just left in place.  It quickly resprouted and now resembles Cousin Itt from The Addams Family.

The joys of arborizing!

It’s Holly’s day…but she’s off playing in a tropical paradise.  So because she seems to be of a sunnier disposition than I am, I’ll post happy thoughts today.

One of my favorite pruning techniques, especially for small urban landscapes, is arborizing.  This is a way of creating small trees out of large shrubs – and often, a large shrub is as much as a small landscape can handle.  Rhododendrons are common landscape plants here in Seattle, and the larger ones lend themselves beautifully to this practice:

  

As you’ll notice in this example, arborizing not only creates an aesthetically pleasing tree form, but also moves the crown away from vehicular and pedestrian traffic.  This protects the plant from damage and enhances access.

This also works wonderfully in landscapes where you would like to have layers of shrubs, rather than one massive plant.  Look at this Ceanothus:

Arborizing this shrub not only allows planting additional plants underneath, but also allows some light into the house (note the window in the background).

Fall is generally a good time to prune (after the crowns have gone dormant).  It’s easier to see trunk and branch architecture in deciduous trees, and generally places less stress on the plant.

If you’ve arborized shrubs before, which species work well for you?  Which ones not so well?

See?  I can be a happy blogger!

Building a better tree? Not in the long run!

One of the landscape tree production practices that drives me absolutely nuts is heading back trees in the nursery to create “columnar” specimens.  It’s easy to find examples of these in Washington state nurseries, like the pathetic oak shown below:

 

Aesthetics aside, let’s focus on how the tree responds to heading back.  The removal of the dominant leader encourages lateral branches below to become more upright; from these laterals, a new leader is selected.  This new upright growth habit is highly prized by many landscape architects and urban planners, as such trees fit more neatly into small urban spaces without interfering with vehicle and pedestrian traffic.  Sure, it works great for a few years.

Now let’s look at these trees a decade or two later.  Branches grow in diameter as well as length.  All of these acutely angled branches begin to grow into each other, creating bark inclusions:

 

What effect do bark inclusions have on the trees?  These fused branches are not strongly connected; in fact, they are likely points of branch failure.  As these branches become larger and heavier, they can create hazard situations if they are near people or property.  What’s happening here in Washington, and probably elsewhere, is that arborists must be hired to prune out some of these branches to reduce the risk of failure and injury.

 
This…most definitely will lead to this…eventually

I can’t understand why this practice is perceived as “building a better tree.”  To me, it looks like creating a maintenance and liability problem down the road.