I disagree with lowering the threshold. Lets be clear here, the existing standard is not actually used to protect gorgeous mature trees, its instead used as a money-making operation by forestry to fund feather-nesting.
You let the trees go, but you charge money for the permit and for replacement trees.
Lowering the threshold wouldn't lead to a greener city, just more paperwork.
I would actually go the other way, but with changes that would make many property owners, especially developers, grimace; I'd bump the number up to 40cm so we only capture the grander, larger, more beloved trees. But I would then deny any non-safety reason for removal. No fee to cut down the tree, you just can't. If its in the way of your proposed building, you can't build the building, too bad.
For reference, (on average), a 45-year old tree might be 30cm; where a 60 year old tree might be 40cm. There's obviously a lot of variation based on species and growing conditions.
I'd spend more time on growing conditions for trees if we want more successful mature trees. That would look like:
- An aggressive program to replace older tree planters/boxes on sidewalks as well as small tree pits that offer less than 30m2 of soil to a tree. Ideally, these would be replaced with trenches that have 2 trees each and share 60m3 of soil or more, with compatible shrubs/perennials than enrich the soil. Feeling generous? Add irrigation.
- Eliminate street parking on select blocks on major roads to create room for more and better trees with wider sidewalks.
- Crack down on illegal parking pads on front lawns and phase-out said pads wherever they fail to provide sufficient room for 1 healthy tree, or where the home already has on-site parking.
- Narrow side street during reconstruction, wherever they exceed 7M in width. If parking demand is low, limit to one loading zone/drop off per block and otherwise remove it in favour of more/larger soft boulevards w/trees. Where parking is high demand, create a bump out every 3-4 spaces that holds 2 high quality trees with appropriate soil volumes and complimentary plants.
- Raise permit parking prices by an average of 100% to fair market value, helping free up more spaces for planting. (over 100% for the cheap, entry-level spaces, slightly less for those at the top of the current pricing) This also more than replaces the revenue from the tree permit process that would be lost.
