Previous Arbor News Publications
Girdling Roots; The Tree Killer
By Susan Tangen Certified Arborist WI 0684A
It hasn’t rained for a few weeks so you decide it is time to water your Norway maple. You get the hose and drag it to the tree when you notice that it just doesn’t
look well; the leaves are scorched and there are some dead branches. When it was planted 15 years ago, you thought everything was done right; the hole was dug at
the recommended depth by the garden center, it was watered when needed, mulched every spring, and fertilized annually. You decide to call a certified arborist to
look at the tree and they inform you that the tree has no exposed root flare. In addition, it has the signs and symptoms of girdling roots. You ask “What are girdling
roots? What caused them? What can be done about it?”
Girdling roots are roots that grow around the stem of the plant. When girdling roots come in contact with the trunk, the radial growth of both the trunk and the root
is restricted which inhibits the normal water and nutrient movement from the roots to the crown. Eventually, the branches will become weakened and the entire tree may
die. Unfortunately, the death from girdling roots is slow and could take up to at least 15 years for the tree to die.
There are several reasons for the development of girdling roots, but the one I most noticed in the landscape is a buried root flare. The root flare is the swollen
area at the base of the tree, where the trunk meets the buttress roots; this area should always be above the soil grade. When the root flare is buried, the development
of girdling roots will most likely occur. In addition, the deeper the root flare is buried, the more likely layers of girdling roots will develop, which are the most
damaging to the tree. Buried root flares can occur by planting the tree too deep, adding excessive soil to the root zone of the tree, or piling mulch against the trunk
of the tree.
The best treatment for girdling roots is to prevent it from happening by planting the tree at the proper depth and not piling soil or mulch around the base of the tree.
If an established tree has girdling roots, the recommendation is performing a non-destructive method of exposing the root flare and removing the girdling roots. However,
it should be noted that this is an exploratory procedure since it cannot be determined, until the root flare and girdling roots are exposed, if the tree can be
successfully treated. For instance, if there are layers of girdling roots, success of the treatment is less than if there is only one or two of them.
Girdling roots strangle trees causing a slow decline and eventual death of the tree. Since all trees cannot be saved by exposing the root flare and removing the
girdling roots, it is important to prevent them from developing. So don’t make the same mistake noticed in many landscapes, leave the root flare exposed.
Benefits of Tree in an Urban Environment
What can absorb pollution, create oxygen, and lower you monthly bills? Why trees of course! Properly planted and maintained trees add value to your property and have a
wide range of benefits. Trees also help reduce runoff from storm water and reduce the heat island effect of buildings and paved surfaces in urban areas.
Deciduous trees placed at the south, east and west sides of your home provide shade against the hot summer sun. A shaded air conditioner functions more efficiently and
reduces operating costs. In urban areas, shaded sidewalks and streets can lower temperatures as trees absorb and reflect light that would normally reach the surface.
Transpiration, the process through which a plant releases water from roots to the atmosphere, also helps to cool the surrounding air. Fall leaf drop allows the winter
sunlight to reach your home, providing warmth and reducing energy needs.
Evergreen trees make excellent wind break plantings, particularly when installed north and west of your home. The most effective wind breaks contain trees that branch
low to the ground and contain two to three rows of staggered trees. Windbreaks should allow some wind penetration; if planted too thickly a partial vacuum can form on
the protected side and mitigate the benefits. Wind breaks reduce wind velocity and can result in energy savings of up to 30%.
Many benefits are not as easily quantifiable as energy bill savings; trees also reduce soil erosion and improve water infiltration into the soil. Storm water runoff is
mitigated as the tree absorbs water; some trees can store over 100 gallons of excess water! Heavy rain is also slowed down and partially retained by leaves in the canopy.
Water absorbed by trees is naturally filtered as heavy metals and chemicals are retained within plant tissues.
Air quality is improved as leaves absorb atmospheric gases and release oxygen. Dust, ash, and small particulates collect on leaves and stems to be washed down to the soil
with the next rainfall. Recent studies have indicated that certain tree species release VAC’s during hot weather. VAC’s or volatile organic compounds, are released from
the canopy and can contribute to ground level ozone production. Oak, sycamore, and willow trees outweigh the drawbacks of VAC’s. Wind pollinated trees can also become
temporary sources of pollution as the heavy pollen load can be bothersome to some people.
Trees provide numerous benefits, from aesthetic appeal to energy savings for your home. Inspection by a Certified Arborist can reveal potential health or structural problems
and keep your landscape at its best. For more information I recommend visiting www.treesaregood.org.
We would like your thoughts! Continue this conversation on Facebook, Twitter, just search for Cassity Tree Service.
We are the Champions
Trees are amazingly diverse; they are also among the oldest and largest living organisms on earth! The largest trees of each species are known as “champions” and are awe
inspiring. Champions are measured by circumference in inches at breast height, total tree height, and average crown spread. Potential champions are carefully evaluated
The longevity of some tree species is truly astounding. The oldest tree species in the USA is the Bristlecone Pine, Pinus arista var. longaeva, which is native to California and Nevada.
The oldest one is located in the White Mountains of California which has an approximate age of 5,063 years.
The largest single stem tree in the USA and the world by volume is Sequoiadendron giganteum “General Sherman” which is located in Sequoia National Park. It is 275 feet
tall, with a 25 foot dameter and an estimated age between 2300-2700 years old. Although it is not the largest tree known in recent history, that distinction belongs to
Sequioa sempervirens “Crannell Creek Giant” that was located in Trinidad CA and estimated to be 15%-25% larger than General Sherman. Unfortunately, it was cut down in
The tallest living tree is Sequoia sempervirens “Hyperion” measured 380 feet tall in 2006 and is still vigorously growing. Astonishingly, it is only a couple hundred
feet from a clear cut area in the Redwood National Park and was 2 weeks away from being cut down. Logging companies feverishly clear cut in this area before President
Carter added it to the National Parks System thereby protecting it.
Wisconsin holds records for our own state champions as well. Wisconsin champion trees are situated all over the state but many giants lie closer to home. Take a look at our
champions that are in our neck of the woods:
*Racine has an; Osage Orange, Maclura pomifera, measuring at 99”CBH (circumference breast height) located on City trunk KR north side of road 1-2 miles west of
intersection of Hwy 31;
Camperdown Elm Ulmus x glabra, 100” CBH located in Burlington NE corner of Crossway & Ketterhaugen through Bong State Park
*Kenosha is home to its share of champions as well; Serbian Spruce Picea omorika 28” CBH at 7504 19th Ave;
Chinese Tree Lilac Syringa pekinensis 67” CBH at 6541 7th Ave;
Common Bald Cypress Taxodium distichum 135” CBH at Bong recreation area E side of access road;
Sweetgum Liquidambar tyraciflua 26” CBH at 6347 47th Ave back yard;
Sawara Flasecypress Chamaecyparis pisifera 42” CBH at 4426 5th Ave
These tree measurements were completed in 2005 and are currently being re-measured. Please remember to be respectful of private property when searching for champion trees.
All champion trees in Wisconsin can be found in R. Bruce Allison’s book, Wisconsin’s Champion Trees, pub. Wisconsin Book publishing.
Proper Mulching Techniques
Benefits of Proper Mulching
Helps reduce soil moisture loss through evaporation
Helps control weed germination and growth
Insulates soil, protecting roots from extreme summer and winter temperatures
Can improve soil biology, aeration, structure(aggregation of soil particles), and drainage over time
Can improve soil fertility as certain mulch types decompose
Inhibits certain plant diseases
Reduces the likelihood of tree damage from “weed whackers” or the dreaded “lawn mower blight”
Gives planting bed a uniform, well-cared-for look
Trees growing in a natural forest environment have their roots anchored in a rich, well-aerated soil full of essential nutrients and soil microorganisms.
The soil is blanketed by leaves, organic materials and living organisms that replenish and recycle nutrients. This environment is optimal for root growth
and mineral uptake. Urban landscapes and new developments, however, are typically harsher environments with poor quality soils, reduced organic matter and
large fluctuations in soil temperature and moisture. Applying a 2-4” (5-10cm) layer of organic mulch can mimic a more natural environment and improve plant
Previous Arbor News Publications
This newsletter has adapted articles from the publications of the following organizations in addition to our original pictures and stories.