HomeMy WebLinkAbout7/5/2022 Item PC, Schmidt (2)
Wilbanks, Megan
From:Richard Schmidt <slobuild@yahoo.com>
Sent:Monday, July 4,
To:E-mail Council Website
Subject:Agenda Correspondence -- public comment
Attachments:council oak gene pollution.pdf
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Dear Council,
Please see attached letter on city-sponsored genetic pollution of native live oaks, a follow-up to previous letter on subject.
Thanks.
Richard Schmidt
1
July 4, 2022
Dear Council,
Several weeks ago I wrote requesting the Council take seriously its obligation to do our city’s
fair share towards the 30 x 30 initiative, and in that context pointed out our tree planting
program, while claiming to plant a few “natives” is actually introducing genetic pollution into
our robust local coast live oak (Quercus Agrifolia) gene pool. I recommended the city sponsor a
nursery program to propagate our very local variant of Q. Agrifolia, plus other local natives,
thus side-stepping the nursery trade’s one-variant-for-everyplace so-called “natives.”
Since the majority of fake “natives” are being planted under city programs (10,000 trees but
also as development mitigation requirements), the city should be offering a solution to the
native tree gene pollution it is otherwise promoting.
It occurred to me after sending that note that the concept of genetic pollution in trees might be
unfamiliar, and that in this instance it could be illustrated quite simply with a photograph of
leaves. That is because the distinct differences in leaf morphology between the nursery
“natives” and our Cerro San Luis Obispo-area natives are so obvious.
In the photo below are twig samples from four “Q. Agrifolia,” the left two of the nursery trade
sort, the right two of our local sort.
One of the nursery trade trees is a newly planted 15-gallon specimen, the other – judging from
its size – is 25+ years old. Both are street trees required to be planted at time of new
construction, presumably required and selected under the pretext of planting natives. Age
differences of the two demonstrate the long-standing and continuing problem of introducing
“alien” nursery-trade genes under the pretext of planting natives.
The two samples on the right are truly native Q. Agrifolia planted in my own yard by bluejays
using acorns from the neighbors’ beautiful native local Q. Agrifolia.
Differences in leaf morphology are obvious:
• Size. The non-native trees have small leaves, the true natives large leaves.
• Shape. The non-native nursery-trade trees have long/skinny lanceolate leaves, the true
natives have broad holly-like leaves.
• Form. The nursery-trade leaves tend to curl under while the true natives are flatter.
These differences are persistent throughout a tree’s life. Walking around town and looking at
the live oaks, I am struck by the fact most of the oaks planted under city development
requirement pretext since natives became fashionable (1980s) are of the nursery-trade genetic
pollutant type. The bluejays will go to work spreading these exotic “natives” just like they do
our true natives.
I don’t think we do right by Nature to risk permanently polluting our true native gene pool with
whatever it is the nursery trade is sending our way. We can do better by finding an alternative
to the questionable product supplied by the nursery trade. I hope you agree with that
proposition.
So isn’t it the city’s ethical responsibility to do what it can to protect Nature by creating a
source for truly local native trees for use in city tree planting programs? Let’s get moving on
fixing this problem.
Sincerely,
Richard Schmidt
Here are some closer-up photos showing leaves – and their differences -- more clearly:
Nursery trade live oak.
Truly local live oak.
Excerpt pertinent to trees from previous letter on ways the city could support the 30 x 30
Initiative.
. . . 4. Use city programs to advance biodiversity, and supplement them with suitable extensions
of existing programs.
• The 10,000 tree initiative included in the CAP could also be an instrument for improving in-
town biodiversity. I say “could” because as being implemented it is not. For example, the
trees being planted with hotel tax revenues are four species, three of which are exotic weeds
(one, Pittosporum, is an invasive exotic weed). The only “native,” Coast Live Oak, will be
procured through the nursery trade, which means it will have genes from who knows where
(but not local) and will introduce gene pollution into our actual native oak population. The
city has the land (City Farm, for example) to raise thousands of actual SLO natives from local
seed. This should become a city-sponsored project to provide planting stock for our urban
forest.
The problem of exotic trees is they generally don’t support local fauna. The ecosystems
supported by exotics (insect communities, for example) are not necessarily those needed by
our local songbirds, many of which are “species of concern.” Natives provide such ecological
services much better than exotics.
• To support native songbirds, the city should encourage owners of urban creeks to restore
some riparian willow habitat. This is hugely supportive of songbirds. I own about 75 feet of
creek. I lived with a habitat of exotic elms for many years, but over a decade ago decided to rid
my creek of elms and plant locally-native willows1 and alders to supplement 2 native live oaks
already present. Today the yard teems with dozens of species of songbirds we never saw
before. This is such a simple way to extend lost habitat, the city should do everything it can to
teach about it and encourage it.
1 Replanting willows is simple. During winter one simply sticks a willow twig in the ground, and most will grow.