Print This Page

Dallas Morning News - January 28, 2021


Root Flares – Key Tree Health


The largest and most healthy trees in the world have dramatically exposed root flares. Why is the proper exposure of the base of a tree so important? Of all the questions I get about insects issues, diseases, damage by sapsuckers, mistletoe, galls and other tree concerns, the most common cause is the tree being too deep in the ground. The best and almost always effective solution is the removal of stuff that is covering the base of the tree – exposing the flare.


Soil being loosened with hori hori knife prior to being blown or brushed away


The reason this so important is that exposing flares allows them to breathe properly. Stress-free trees have a built-in power to protect and/or heal themselves.


Exposing the base, root flare, trunk flare or simply flare (all these terms are fine) is the first and most important step of the Sick Tree Treatment procedure. Almost all trees and other woody plants have been planted too deeply by the growers, aren’t uncovered by the nurseries, get planted too low by landscapers and homeowners and then have too much mulch added on top. The result is buried flares and stressed trees.


Soil being removed from flare with the air spade


Tree flares are transition zones, but more part of the trunks than the root systems. When flares are covered with soil, mulch or anything else, they stay overly moist, don't breathe properly and tree health suffers. Pests can detect that and attack. That's their job. When the soil is removed from the flare, you can almost hear a sigh of relief from the tree and it starts growing better while shedding pests. Exposing the flare often exposes other tree problems also like circling and girdling roots or drip irrigation that's been buried and forgotten about. Removing debris and damaging roots is critical to the health of the tree. The hidden roots can cut into trunks and flares causing short and long-term injury. They should be removed just like problematic limbs.


Uncovered tree base showing buried drip irrigation and problem roots that need to be removed


Although best done by arborists using an Air Spade or Air Knife, flare exposure can be done with hand tools if done carefully. I use the hori hori (Japanese planting) knife to loosen the soil and then a battery-powered blower to blow the soil and mulch away. For professional help, make sure to hire a tree care company that understands the importance of exposed flares, has an air spade device and uses organic techniques. If the company you are using or considering using is not positive about these points, keep shopping around.


Some buried trees will have spaghetti-like roots trying to reach the surface for air. They should be removed and the hole left open exposing the flare


There is a video of me exposing the base of one of my own trees on YouTube, info in the Fabulous Trees Slide Show on and lots more information on this critical part of tree care in the TORC (Texas Organic Research Center) on-line course. There will be a short course on the Sick Tree Treatment specifically in the near future. I'll keep you posted.





  Search Library Topics      Search Newspaper Columns