Improving Tree Structural Stability via Cabling

bigbertha.jpg

This is Big Bertha the fir tree. She lives south of Mt Horeb and was named by a tree loving 7-year-old. The mother of the boy called us and asked if we could stitch it back up after a summer storm. The possibility of cutting it down due to the split between the two halves was too much for the boy to manage and he pleaded with mom to call us.

The friendly guy at the bottom of the photo is Alex; he is standing in front of his handy work. He cleaned up the failed branch (see cut on trunk) and then took it upon himself to install the dynamic cables; you can see two cables there, installed as high as possible. These cables are more effective the higher up you put them in the tree.

Cables have a tensile strength of over 10,000 pounds making them very strong. The best feature of the support system is its stretch which allows the tree to move freely compared to rigid static steel cables. The other nice attribute of dynamic cables is there is no hardware installed or drilled into the tree. A simple knot is tied around the branch with room for future growth.

The one drawback to the dynamic cable is its lifespan. These cables need to be inspected every couple of years and replaced after 5-10 years due to potential wear and degradation over time. When compared to static cables the dynamic is a bit less expensive in the short term, but in the long run they would likely work out to be the same amount of investment depending on how long the tree remains on the property. 

Over the years, dynamic cabling has allowed us to prune suspect branches aggressively to reduce risk and then install the cable to provide a bit more insurance against branch failure. This is a tool that can help keep trees safely in the landscape longer. Long live Big Bertha!
 

Bring Back Paper Birch!

Paper Birch and its white chalky bark is well recognized across the state. In the last 20 to 30 years, landscapers and nurseries have strayed from the paper birch to whitespire birch or grey birch because paper birch has a reputation for being susceptible to bronze birch borer, a native pest. In reality, when properly placed, a paper birch can thrive and not succumb to bronze birch borer. Paper birch is an understory tree and should be planted in partial shade among other trees. Cool root zones are the key for this tree. Bring back that native yellow fall color to your yard!

 A single stem paper birch in a customer’s yard. This stem sprouted from the stump after the original tree was cut down due to structural concerns.

A single stem paper birch in a customer’s yard. This stem sprouted from the stump after the original tree was cut down due to structural concerns.

I like the upright growth habitat favored by the paper birch. Fewer branches gives the paper birch an aesthetic advantage over the messy/super thick grey birch. We often prune grey birch to look like paper birch (doesn't that sound silly?) by removing or thinning the branching to clean up its appearance.

 Before: A grey birch prior to Alex thinning the canopy to improve its appearance.

Before: A grey birch prior to Alex thinning the canopy to improve its appearance.

 After: Notice how many fewer branches the tree has.

After: Notice how many fewer branches the tree has.

We plant single-stem paper birch each spring as a bare root tree. Go to our store or contact us today to inquire about purchasing a paper birch for your yard. If you are inclined to plant a paper birch yourself, AWESOME! Remember that birch is an understory tree and should be planted in partial shade. I have noticed that paper birch on the east and north side of homes do well because the house shades the root zone in our hot summer afternoons.

 

 

Autumn Blaze Maples: A Beautiful, Fragile Tree That Needs Regular Care

The Autumn Blaze maple tree is a hybrid species comprised of half red maple and half silver maple. The combination has been popular for 20 years in commercial and residential plantings thanks to the combination of gorgeous fall color and rapid growth - exactly what homeowners are seeking.  In addition, the Autumn Blaze is very hardy and can withstand a wide range of climatic conditions.

The big drawback of the Autumn Blaze maple is its structural weakness. The tree tends to crack easily at branch unions, which leads to broken branches and property damage after even mild storms. To avoid problems with Autumn Blaze maple trees, property owners must invest in regular tree care.

Maintaining autumn blaze maples requires regular pruning every 3 to 5 years.  Regular pruning helps keep the structure of the tree sound and prevent some of the issues discussed/illustrated below. I planted an Autumn Blaze at my parent’s house 15 years ago and I prune it every year! My dad is always amazed at how much wood I remove from the tree on a yearly basis.

The two major maintenance issues for this tree deal with the roots and the canopy.  For a discussion on roots and root zones check out some of our other blogs related to that topic. We will discuss canopy management below.

Canopy Maintenance Prevents Broken Branches

If an Autumn Blaze maple tree has been in your landscape for more than five to tens years without any structural or upper canopy pruning, please contact a certified arborist ASAP because these trees require regular pruning.  I’m not exaggerating here, they really do need regular care in order to stay in your landscape long-term. Unmaintained trees develop weak branch attachments (cracks) prone to failure, which ultimately can mean losing the entire tree.

The lowest branches on this tree have strong, circular, horizontal unions.

Past the first few limbs (at left), this tree's unions are deep, vertically-oriented V's. Notice how every union has a vertical crack extending down from the bottom point of the branch union? This is trouble waiting to happen.

This blog features a 14” diameter Autumn Blaze maple that has been growing for 15+ years (see below photos). Since the upper canopy has never been pruned, all its major branch unions (where they connect to the trunk) have developed significant cracks due to included bark. Included bark is bark wedged between a v-shaped branch union of co-dominant stems. In the photos above, the lower branches have strong open unions, while the upper branches that look like v's have included bark. These are branches are most susceptible to high-wind branch failure, also know as sail effect. So this tree needs some extra TLC in the form of dynamic support cables. The cables provide extra support for the weak v-shaped branch unions that are synonymous with Autumn Blaze maple trees.

Reduction Cuts Reduce Canopy Load

With this particular tree we will reduce (shorten) branches competing with the central trunk in order to encourage the central trunk or leader to assume the dominant position in the tree (see below photos). By reducing competing leaders you minimize the risk of branch failure and redirect energy from those branches by removing live tissue.

Before pruning. Notice there is no clear central trunk.

 After pruning. Reduction cuts have significantly decreased leaf load in the entire tree and limited competition for leaders, encouraging the central trunk to become clear and dominant.

After pruning. Reduction cuts have significantly decreased leaf load in the entire tree and limited competition for leaders, encouraging the central trunk to become clear and dominant.

Can you believe this much pruned wood came out of this Autumn Blaze? It's difficult to tell from the before-and-after, but it's a lot of wood!

Dynamic Support Cables

This tree is very consistent in terms of (poor) form; without regular pruning from the time of planting it is almost certain to have structural problems. Because this tree had not been previously pruned, it requires more than just pruning; dynamic support cables will be necessary to provide extra support for the weak unions described above. These support cables are permanent fixtures in the tree. Please read Support Systems for more information on dynamic cabling.

Brent adds two dynamic support cables in this Autumn Blaze maple tree to help prevent the trunks from cracking under leaf and wind stresses.

The dynamic cables are placed in the upper canopy and are not very noticeable from the ground.  They will provide added support for the tree making it more likely to withstand heavy weather events throughout the year.  Now that the tree is pruned and the cables are installed it you can enjoy its ever-expanding shade and wonderful fall color.