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FogKat
01-03-2011, 04:04 PM
As a landscape designer I've noticed my fair city of OAK-land [ahem] has NOT ONE native tree species on it's "official street tree" list.

Are there any natives anyone would recommend as being promoted to this list?

Many thanks!

PeterJWarner
01-14-2011, 04:20 PM
The circumstances in which most "official street trees" are discussed and selected is critical to addressing this question.

While I'd like to advocate planting LOCALLY native trees -- not California fan palms or Joshua trees in the Bay Area -- most northern California native trees are not adapted to pavement, soil compaction, vandalism, air pollution, drainage constraints, and other urban conditions. In almost all urban situations, native trees cannot thrive, and their poor performance when forced into these situations provides cynics with more reasons not to plant natives in other, more suitable situations.

A sidewalk or median strip of 2- or 3-ft. width is not a good situation for most trees, native or not, and I can't think of a native tree that would thrive in such a situation. In parks or areas with more extensive root and canopy space, watering, mowing, and public use regimes are often ill-suited to native trees, most of which evolved in summer-dry climates over thousands of years. Some native trees will adapt to areas of poor drainage or compacted soil by producing a proliferation of surface roots, resulting in maintenance problems and safety (walking) hazards to sidewalks and street pavement.

Northern coastal California has perhaps 20 or so native tree species, and for those I can think of, a street-side planting is not in the plant's best interest, for thriving and surviving long-term. Although many of the "street trees" chosen by municipal agencies are abhorrent choices (they're invasive ecologically, invasive physically -- roots, etc. -- or just ugly or messy), I really can't recommend most native trees for street planting, unless they're provided with sufficient space for roots and canopies. I might be overlooking some possibilities, but urban streets are not viable ecosystems for most native trees.

FogKat
01-17-2011, 02:38 PM
Thanks for your response.

>In almost all urban situations, native trees cannot thrive

But that's the case with MOST trees, native or not.

Obviously some do better than others and, in that regard, I've researched the average street tree to last only anywhere from 7-13 years. Given that, I'd prefer to plant a native if any were feasible.

Interesting recent article about street tree planting from ASLA:
A New Way to Plant Urban Trees (http://dirt.asla.org/2010/11/18/a-new-way-to-plant-urban-trees/)

Hopefully climate change will force the issue of giving street trees greater consideration in the planning and implementation of their planting environments.