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Communities - Habitats
The Valley Grassland plant community is a result of
a few soil/water issues.
1. Seasonal flooding.
An account from an early American explorer:
“We again looked toward the north, and
between the low range to the northwest and the Sierra Nevada we saw an
immense plain [Footnote 380] which on that side apparently ran in the
same direction as the Sierra Nevada; but on the other side it opened
about to the west, with such a sweep that it embraced almost the entire
semicircle of the horizon. This is the plain through which the sea of
fresh water extends, not continuously but in places leaving great areas
uncovered or with little water, forming those great green tulares that
begin near the mission of San Luis. According to their direction and to
this account they must be more than a hundred leagues long to this
place, not counting the distance which they may extend above, for we
were unable to see their terminus, and in width they must be some
twenty-five or thirty leagues. I surmised that these tulares must run
to the vicinity of the port of Bodega, and that the green field which
Captain Don Juan de la Quadra saw to the east of his port must have
been tulares like these which we saw here, or that they might even have
been the same ones, extending as far as that place. “ Font,
1776[a league is 3 miles]
2. In late spring the soil drains and becomes very
dry and alkaline in a matter of weeks.
“All the ground was covered, not with grass and
green leaves, but with
radiant corollas, about ankle-deep next to the foothills, knee-deep or
more five or six miles out. Here were bhia, maderia, burielia, chrysopsis,
etc., growing in close social congregations of various shades of
yellow, blending finely with the purples of clarkia, orthocarpus,
whose delicate petals were drinking the vital sunbeams without giving
back any sparkling glow.
Because so long a period of extreme drought
succeeds the rainy season, most of the vegetation is composed of
annuals, which spring up simultaneously, and bloom together at about
the same height above the ground, the general surface being but
slightly ruffled by the taller Phacelias,
Penstemons, and groups of Salvia carduacea,
the king of the annuals.” Muir
3. Some areas of the oak woodland plant communities
can have pockets of grassland where the soil is too shallow to support
These areas are probably not a true grassland
either, more like a grass, bulb, forb and wildflower land. They are a
part of the oak savanna and woodland.
4. Many areas (particularly within the San Joaquin
Valley) have high boron or sodium soils.
High amounts of boron (5 ppm or more) or sodium(250
ppm or more) or other element imbalance severely limit evergreen bushes
and trees. Short-lived perennials, grasses and wildflowers can get
around the problem by flourishing in spring after the winter rains have
diluted the salt content down to a more reasonable number. As the soil
dries out, the salts come back to the surface and these plants shut
down and go dormant. The areas right along the coast that have this
soil problem are called coastal prairie.
5. Many areas of the Valley Grassland plant
community may have been freshwater marshlands.
We know the Sierran snow melt filled up much of the
Sacramento and San Joaquin valley floors; there is just not enough
information as to how much it filled and how long the water stood. If
the soil stood for a month under water, it was probably a grassland. If
the soil stood for three months or more it was probably more a seasonal
marsh. Anza's men measured an ebb and flow of 8 or 9 feet within the
'vast inland freshwater sea' and it was approximately “breadth
some twenty-five or thirty leagues”[league=three miles] wide. Now
the valley floor from his vantage point was only about 70 miles wide,
so the water must have been present from the Sierran foothills to the
coastal foothills. In a high snowfall year with a warm spring as Font
saw it the water level in the San Joaquin Valley may have been to 60-70
feet above sea level (about the elevation of Los Banos).
6. The historic data of what and where the
grasslands of California were is very poor, maybe non-existent.
Just a few words. It was discovered by Europeans in
1776 and almost completely destroyed ( drained and plowed ) by 1840 or
1850. It was one of the largest marshlands for waterfowl in North
America; now ,it is but a minuscule patch of its former self.
To plant a Valley Grassland plant community in your
garden, you will need shallow soil, and/or soil with high boron or high
sodium, or low rainfall, (in other words , be a valley resident!) to
make the best plant community. But you will still have to weed a lot!
If you can suppress the weeds for three years, you may have a chance at
a fairly stable plant community. If you live in the Sacramento or San
Joaquin Valleys you are one of the luckiest people ever, because you
can grow one of the rarest plant communities in the world! In other
areas of California, without the distinct soil and climate conditions,
you can grow this plant community but you will be constantly weeding
out the large weeds, alien grasses, and weedy trees that find their way
Coyote, Western meadowlark, Burrowing owl,
annual wildflowers, some rushes (Juncus spp.) and
(Stipa (Nassella)spp.) and Bluegrass (Poa
Soil and climate notes:
An area of poor drainage, wet in winter(often under
water) dry in summer. Rushes, sedges in winter, wildflowers in late
spring, bunch grasses in summer, baked salt flats in fall.
Valley Grassland would have been
better named Valley Wildflower Marshes, or Valley Seasonal Flood Plain
because for the most part, grasses were not a major component of the
plant community. This plant community is commonly misunderstood and
misrepresented in its species composition and ecology. It was Not like
the prairie of the midwest.
This is a map of the areas of California that are
now probably Valley Grassland. Before 1830, the middle areas, maybe all
but the edge dots were freshwater marshes.
Towns like Terra Bella or Davis come to mind.
(Again, you only find a grassland in patches in California, in
areas of high sodium or high boron, shallow soils, or serpentine, or
another element imbalance, or seasonally flooded for a short period of
list of California native plants that grow in the Valley Grassland