Sometimes the best way to begin a story is with the ending. A typical spring storm has just toppled your front yard maple tree, snapping at the ground. Not just your tree, but many in the neighborhood as well. Luckily no one was injured. You call around for bids to remove the remains of a tree that was alive just a few hours before, sick at the thought of how long will this take and how much it will cost. The tree you loved and tended, that blocked the afternoon sun that birds nested in. How strange, the weather was not that bad? Why isn't everyone's tree down? You start over with a new tree and the clock begins again until it too falls over.

What appears to be killing the tree may be masking a much more deadly cause. You may think the wind felled the tree, but it's the condition of the roots. The obvious cause of death gets the blame, letting the initial cause of decline off the hook. The bottom line is that small stresses can add up to one serious problem.

Placing organic or hardwood mulch where is shouldn't be is devastating for trees. Piling mulch high against the trunk creates the ideal conditions for growing roots where they don't belong; against the trunk. Roots follow the path of least resistance, encircling the trunk, never changing direction into the soil. Over time, the trunk decays at the point of compression and roots cannot anchor the tree because they are growing in a circle. A tree is only as strong and stable as its weakest point, and a decayed, compressed trunk is weak. Every year is a ticking time bomb of strangulation, where one day it too will fall.

Properly applied hardwood mulch is a wonderful thing for trees. Mulch should be in the shape of a doughnut, not a volcano. Mulch protects the tree from lawn mower or string trimmer damage, while keeping the soil moist and stabilizing the temperature in summer and winter. Organic mulches eventually decompose and improve the soil structure.

Mulch should never be more than 3 to 4 inches deep when first placed, and should never touch the bark of the trunk. Do not place mulch over the root ball. I often tell clients don't use less mulch, just spread it out over a wider area. A quick Google search revealed 275,000 results about the damaging practice of Mulch Volcanos. The information is out there.

Yet I see mulch volcanos everywhere, especially in contractor planted landscapes such as McDonalds and Home Depot that should know better. Sending out seasonal workers to "mulch the trees" leaves a lot of room for interpretation. And why would homeowners do any different when they see contractor mulch volcanos and think more is better. Creating specifications for applying mulch and checking on the finished product is a first step. Educating the public is another.  

 

Trees die for all sorts of reasons. Unfortunately it's the little things we do that can make the difference between life and death for a tree.

 

Girdling roots killed this tree, not the wind. The roots grew in the mulch that was maintained over the root ball and on the trunk for many years. Roots enjoy growing in mulch so keep it at least 12 inches from the trunk so this does not happen.

    

After the excessive mulch has washed away, a mess of circling roots can be seen.

 

If mulch is properly applied, in the shape of a doughnut, the root flare is visible.   

 

Typical mulch volcano on a stressed out tree. It could be the person applying the mulch doesn't want to smother the grass, so they place it as close to the tree as possible.

    

What is normal? You never see trees in the forests with piles of mulch around the base of the trunk. Most trees in nature exhibit a characteristic flaring of the stem near the ground, such as this healthy elm.

    

 

This tree was mulched by the developer in 2017. Years later when the dies or falls over from stem girdling roots it's the homeowner and the community who will feel the loss, not the developer.

For more information on how excessive mulching can cause strangulation.

• Compete the application
• Pass the certifying exam
• Pay the yearly fee
• Hold the appropriate insurance
• Fulfill continuing educational requirements