[Website Administrator’s Note: This opinion states that the tree has a diameter of 93” and a corresponding critical root zone radius of 93’. The diameter measurement was in error. The actual diameter is closer to 64” and the critical root zone radius is 64’. The 1/2 CRZ 32’ and the 1/4 CRZ is 16’ This was an inadvertent measurement error. The opinion will be revised shortly to reflect the correct radius. The change does not change our opinion that the tree is endangered by plans for construction and street widening within the CRZ perimeter]

By Del Britton

International Society of Arboriculture (ISA) Certified Arborist

Stephenville, Texas

Opinion - Ancient Live Oak

Concerning Live Oak with a diameter of 93”. The tree is located at approximately 200 N Vine Street inStephenville, Texas. It is on city property. The canopy is generally healthy in appearance.The tre e has a wound where a limb was broken off on the street side and has not been properly pruned. A sidewalk existed (now removed) inside the “Quarter Critical Root Zone”. As much of 3’ compacted fill dirt has been placed over a large area of the “Tree Protection Zone”. Some minor limb damage has been done by current construction activity.

There is evidence of intention to protect the tree from the construction process and the actual building. The protection is inadequate for several reasons.

The existing orange mesh barrier is inadequate as protection. It is physically flimsy and being ignored by workers in several ways. The area inside of that barrier has already been violated with equipment traffic and fill soil was placed inside the barrier.

The barrier does not encompass a large enough area. Much of the existing barrier is placed inside the minimum distances from the tree.

The current barrier has erratic placement at distances from 35 to 54’ from the tree.

There is no interior or Quarter Critical Root Zone marked or protected.

ANSI Standards would require noting and considering the complete Tree Protection Zone area of a minimum of 1 foot per diameter inch. For this tree a 93’ radius – at minimum.

The Quarter Critical Root Zone (CRZ) should be 24’ at a minimum. I would recommend increasing it because part of the trees root zone on the opposite side is restricted by a street. The streets effect probably increases reliance on the remaining root zone area. No changes or traffic should be allowed on this area.

The Half Critical Root Zone (CRZ) should be 47’ at minimum. A maximum of 4” of additional coverage or 4” removal of soil on 50% of this area might be tolerated by the tree.

Old trees like old animals do not tolerate damage as easily as younger ones. The minimumstandards may not be adequate.

Del Britton, ISA Certified Arborist 4368A