Critical root zone

[yibida]

Just a quick question about critical root zones and how to determine what formulas Arborists are currently using, could someone post an example of any tried and proven methods or should I stick with the old ten times the diametre of the trunk / or D.B.H?

 

[Thillmaine]

Crz

Typically the critical root zone used in construction and compaction issues is just the dripline...mulch with chipos heavlily and try not to drive machines over it...If you thinking about transplanting a tree tyhe formula is 1inch of trunk, 10 inches of rootball

 

[BC WetCoast]

Municipalities here generally use the dripline, although there is others, such as 1'/1". Most tree bylaws here, when dealing with construction require solid fencing around the root protection zone (plastic snow fence with a solid wood frame) and no storage of material allowed in the zone.

Waste concrete and flushings from concrete truck cleaning are also not allowed to enter the zone.

 

[M.D. Vaden]

Sometimes its the most you can get away with and still save the tree.

With some trees, even saving half the drip-line width would render use and access to a property null and void.

In that case, the tree would have to go.

I'm not sure if I use a formula as much as trying to figure out the farthest possible that everything can be placed from the tree.

If there is a sidewalk - how far can it be away? If it can't be far, how skinny can it become.

If there is a fence, how few fence posts can be used, and can they be stretched farther apart than usual to damage less roots.

It there is a driveway, can it be curved rather than straight?

Almost more than measurements, it becomes a matter of how many things can be modified and moved. Or eliminated.

 

[ATH]

Can't disagree with anything said...but to the original question, Ohio State does have a good publication on the matter. The page on soil compaction has a formula based on species and vigor (age). (Just note the chart is labeled wrong. The column title for the 2nd and 3rd columns need to be switched.) Whether you use the formula or not, there is good information in that book.