Dallas Morning News - February 4, 2021
Root flares #2 Follow Up Questions
Questions related to root flare exposure are on the increase and that's good. Lot of response to last week's column on the subject.
One of the most common questions I get is why hasn’t my tree care company recommended this procedure. Well, many people in the tree business were not trained in this technique and don't really understand how to do it correctly. Some of the universities are making some steps that direction, but many of the tree care companies are run by people that learned the tree business from others that learned from on-the-job training. So it's pretty new technology in general, some trail blazers have great expertise and volumes of proof of efficacy.
Age is not a factor in deciding whether or not to expose flares. Several feet of soil was removed from the state champion pecan and it has responded beautifully
Sometimes homeowners are confused about the importance of root flare work because their trees are old-ish and seem to be heathy - so why is the work needed? People in this category are usually greatly surprised how well treated trees do compared to how they looked and grew before the work was done. Disappearance of mistletoe, sapsucker damage and other pests always grab their attention. Tree age has little to do with whether the work is needed. The national champion pecan tree in Weatherford has had more than 4 feet of soil removed from its base and this great tree is many hundreds of years old.
Some people scratch their heads about why certain trees can tolerate being too deep in the soil more than others. Bottomland trees such as green ash, pecan, sycamore and others can better tolerate the moist soil covering there flares – but, they will grow better and have fewer pests if uncovered and respond just like the more drought tolerant trees.
Water standing around exposed trees is usually nothing to worry about, but drainage can be added if necessary
Water standing in depressions created when uncovering root flares raises questions. You might not like the look of the depressions at the bases of trees, but water standing temporarily is not a big concern. Remember that before the work was done, moist soil was against the flare and trunk all the time. If water after a rain stays at the tree base for a long time because of heavy soil or poor grading on the site, drainage can be added. Dig a ditch from the depression out to a lower point on the site and fill the ditch full of crushed gravel all the way to the surface of the ground. Pipes and filter fabrics are not needed. Mulch can be used to cover the surface of the gravel-filled ditch but grass and other plantings will cover it fairly quickly.
You should be able to stand on the flares of properly exposed trees - as here with the Arkansas state champion magnolia
The timing question is simple. Do the work as soon as possible so the trees can get on their way to better health. Winter is the ideal time and spring is probably the most questionable time, but competent arborists are doing this work year round.