digging for the root flare - when NOT to?
We all talk about planting new trees and finding the root flare. While this makes sense, I think there are cases where it's best NOT to do that.
Example: Many trees, when young, either have an entirely fibrous root system, or, a strong taproot with no structural side roots to speak of for several years.
I've dug up volunteer oaks that were maybe half an inch in caliper, that really had nothing but a taproot and a bunch of fibrous side roots near the top, but had some thicker branch roots several inches down.
I know this tree wasn't "too deep" because it sprouted from an acorn on its own. However, someone looking for a root flare could have torn off roots off the actual taproot until the branches started, and end up planting the tree with 5" of taproot sticking up!
I've seen the same thing when using air-pruning pots, esp. on Quercus and Aesculus - in both cases, the roots that grow in response to air pruning are very fibrous, and create no "root flare" initially, and the only thicker, more structural roots sprout near the air-pruned base of the taproot, especially after up-potting it later on. I've got some Q. coccinea and michauxii right now - I have not unpotted any of these ones, but did "sacrifice" one earlier this summer to satisfy my morbid curiosity. The only place that looked like a "root flare" was at the area where the taproot initially air pruned, where several thick roots branched right off the bottom (like a multiple taproot). There were plenty of roots above this point, but all very fibrous wiht no structural thickness at all. My guess is it will take a few years for a few of those fibrous upper roots to thicken and turn into structural roots, and the rest will be aborted as more feeder roots develop further out from the trunk as the tree and the root system grows.
If someone were planting one of these seedlings, and looking for a "root flare" - they'd tear most of the feeder roots off the taproot, assuming they were adventitious roots.
I think we have to consider the age and species when looking for a root flare, in other words. Strongly taprooted trees probably won't have much of one for several years.
This post was edited by hairmetal4ever on Thu, Aug 21, 14 at 12:23