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🌳Petaluma Tree Protection Ordinance:

This is the moment.

 

 

 

Why Save Trees at Six Inches Trunk Diameter?

 

Petaluma needs more trees. ReLeaf is doing its best to plant them.

But newly planted saplings take years to provide the climate, environmental

and social benefits that mature trees are already providing.

 

   Protecting our existing mature trees is essential.
We need a new Tree Protection Ordinance to protect many of these trees.

Why protect trees at and above six inches in diameter (measurement of DBH is 4 1⁄2 feet up the trunk)?
We know that trees can grow slowly. A six-inch tree could be anywhere from 10 to 30 years old.

According to dendrologists, “…there is a direct relationship between tree diameter and tree crown.
The bigger the tree’s diameter, the greater the amount of foliage it has….”
“Large trees are greater functional contributors than small trees with respect to ecosystem services….”

Examples of averages for 6” DBH trees:
• Buckeye: 30 years old
• Coast Live Oak: 12 years
• Bradford Pears: 18 years
• Black Oak:  30 years
• Sycamore: 24 years
• Redwood: 24 + years

Below is a Black Oak, just beginning to bud out this spring, in the field
below Petaluma Junior High School. It’s DBH is slightly larger than 6-inches at 6.37.
This tree is roughly 30 years old.

1 https://bio.libretexts.org/Bookshelves/Botany/Forest_Measurements_-
_An_Applied_Approach_(DeYoung)/03%3A_Tree_Diameter/03.1%3A_Why_Tree_Diameter
2 https://www.mdpi.com/1999-4907/11/2/135
3 https://treecarezone.com/tree-age-calculator/ 4 https://virginiatreecare.com/tree-age-calculator/