Layers are available in several Calflora applications
that use Google Maps, including
Observation Search.
The map applications can show one polygon background layer at a time.
When a background polygon layer is selected, and you click on the map inside of a polygon,
you will see the name of the polygon below the map.
County Lines and Streams can be turned on
at the same time as a polygon background layer. These two layers are lines, not polygons,
and so can be superimposed on top of the selected polygon layer.
Polygon background layers are divided into four groups:
Region, Grid, Climate, and Soil.
Click on a group name -- for instance Region -- to see all of the layers
within that group.
Then click on the name of a layer -- for instance Protected Areas (CPAD) --
and the colored polygons of that layer will be superimposed on
top of the Google Map.
Note that not all layers are available at all zoom levels.
The four checkboxes at the bottom control the appearance of
colored polygons in the selected background layer.
If the appearance of the polygons is too subtle, you can
emphasize the outline of each polygon, or ask for
a darker background color for each polygon.
Here is an example of the Climate / Precipitation
layer with darker background colors and a thick white
outline (click to see it "live").
Streams
Click on Streams to see rivers and creeks on the map.
If you are zoomed way out, you will only see the longest rivers.
As you zoom in, the shorter streams appear.
When you check Stream names, a stream icon
will appear at the end of each creek or river.
When you click on the icon, you see the name of the creek or river, and the name
of the stream that the creek or river flows into.
For instance, in Monterey County,
the icon for the creek called Arroyo Seco
appears at the end of the Arroyo Seco, where it flows into the Salinas River.
When you click on the icon an info window pops up describing the junction:
Arroyo Seco / Salinas River
The course of the stream itself -- the Arroyo Seco -- is highlighted in blue. The course of the
downstream creek or river -- the Salinas River -- is highlighted in green.
Uncheck Stream names to clear the map of all stream icons
and all stream course highlighting.
If you move to a different location on the map or change zoom level, and would like to see
stream name icons at the new location, press the refresh button
.
The Streams dataset is from the May 27, 2019 version of the
California Department of Fish and Wildlife
California Streams dataset.
National Hydrography Dataset (NHD) high resolution NHDFlowline features for California were originally dissolved on common GNIS_ID or StreamLevel attributes and routed from mouth to headwater in meters. The results are measured polyline features representing entire streams.
The named streams from the California Streams dataset are shown in Calflora map applications.
If a named stream flows into an unnamed stream, that unnamed stream is also shown,
with a label like "uns123". Many of these unnamed streams are canals
or other engineered hydrologic features.
REGION LAYERS
County
If this background polygon layer is selected,
you will see county boundary lines (the same as County Lines above) for California counties.
The county polygons themselves are not colored.
However, when you click on the map inside of California,
you will see the county name below the map.
The California Protected Areas Database (CPAD) is a GIS inventory of all protected park and open space lands in California. The database contains lands held in fee ownership by public agencies and non-profits.
The units level of this database is shown in
Calflora map applications. Click in an area to see its name.
For areas with restricted access or no access to the public,
the warning is included after the name.
For instance
San Francisco Watershed Lands - restricted access
No Access
Restricted Access
Park or Open Space area; Public Access
Federal Land (other than National Parks); Public Access
Calflora map applications can show the four levels
of this dataset listed on the right.
Which level is shown depends on how far in the map is zoomed in.
For a more detailed view that includes languages, territories, and overlap, see the
Native Land Digital map.
Achumawi
Atsugewi
Cahto
Cahuilla
Chemehuevi
Chilula
Chimariko
Chumash
Coast Miwok
Costanoan
Cupeno
Eastern Miwok
Esselen
Foothill Yokuts
Gabrielino
Halchidhoma
Hupa
Ipai
Karok
Kawaiisu
Kitanemuk
Konkow
Lake Miwok
Lassik
Luiseno
Maidu
Mattole
Modoc
Mohave
Monache
Nisenan
Nomlaki
Nongatl
Northern Paiute
Northern Valley Yokuts
Owens Valley Paiute
Patwin
Pomo
Quechan
Salinan
Serrano
Shasta
Sinkyone
Southern Paiute
Southern Valley Yokuts
Tataviam
Tipai
Tolowa
Tubatulabal
Wailaki
Wappo
Washoe
Western Shoshone
Whilkut
Wintu
Wiyot
Yana
Yuki
Yurok
GRID LAYERS
Geographic Grids
Quadrangle
USGS quadrangle.
In most of the continental United States, quadrangles
are a geographic grid
where the side of a grid cell is 1/8 of a degree:
There are also irregular quads around islands and on the coast.
Quadrangle / 4
Quarter quadrangle.
This is a geographic grid where the side of a grid cell is 1/16 of a degree.
(When Calflora observations are obscured, they are displayed
at the center of the containing quarter quadrangle.)
30 arcseconds
This is a geographic grid where the side of a grid cell is 1/120 of a degree.
5K The side of a grid cell is 5 kilometers; the area of a cell is 25 square kilometers.
2K The side of a grid cell is 2 kilometers.
1K The side of a grid cell is 1 kilometer.
100 M The side of a grid cell is 100 meters.
CLIMATE LAYERS
Each climate and soil layer described here is
presented as a abstract factor
contributing to the characterization of a location.
The choice of which factors
to show as layers on Calflora maps is informed by
USDA PLANTS Conservation Plant Characteristics
(particularly Growth Characteristics),
but within the pragmatic bounds of what data is available.
The goal is to be able to use these factors as predictors
of where various plants are likely to grow.
For predicting where a plant may grow,
it is important to know the minimum annual precipitation
it requires (and for certain plants,
the maximum annual precipitation it will tolerate).
157 inches
399 cm
133 inches
338 cm
107 inches
272 cm
81 inches
206 cm
61 inches
155 cm
37 inches
94 cm
17 inches
43 cm
3 inches
8 cm
As presented in Calflora map applications, the colors
indicating climate layers are continuous.
Colors associated with selected values of Annual Precipitation
are shown here.
Wet Season
The number of wet months, as derived from
monthly average precipitation
(1981 - 2010) cell data.
For a particular month, an 30 arcsecond cell is considered wet
if it receives at least 1.3 inches of precipitation.
As a characterization of location, this is similar to
annual precipitation, but
indicates the duration of a season during which rain is likely.
12
months
10
8
7
6
4
3
2
0
July High Temperature
based on average maximum monthly data during the period 1981-2010.
56 °F
13 °C
68 °F
20 °C
80 °F
27 °C
92 °F
33 °C
104 °F
40 °C
116 °F
47 °C
December Low Temperature
based on average minimum monthly data during the period 1981-2010.
8 °F
-13 °C
16 °F
-9 °C
24 °F
-4 °C
32 °F
0 °C
40 °F
4 °C
48 °F
9 °C
Accumulated Temperature
based on average mean temperature and average minimum temperature
monthly data during the period 1981-2010.
This is a measure of accumulated heat during those months
during which the minimum temperature is greater than 43 ° F
(6 ° C).
It is related to the concept of
degree-days,
but unlike degree-days calculated for a particular year,
this number is based on average mean temperature.
It is roughly equivalent to an annual sum of degree-days during the growing season.
In the context of these climate factors, accumulated temperature
can help determine which places are too hot for a plant.
It is particularly useful for differentiating very hot places (Death Valley)
from moderately hot places (Fresno).
Temperature Range
Calculated as July High Temperature
minus December Low Temperature
per cell.
In climate modelling, temperature range is akin to
temperature seasonality.
In the context of these climate factors, temperature range
is useful for differentiating coastal areas from inland areas.
Coastal areas typically have a narrower temperature range than
inland areas.
Two Coastal Vacciniums:
These two plants share much of their geographic range, but
parvifolium extends further inland than ovatum.
The difference is reflected in the Temperature Range value for each plant.
The image below is a screen shot from
What Grows Here,
showing occurrences of the two plants in Humboldt County
with Temperature Range as the background layer.
Note how the background color reveals temperature range differences between
inland mountains (green ~ 48° F) and valleys (orange ~ 66° F).
10 °F
-12 °C
24 °F
-4 °C
36 °F
2 °C
48 °F
9 °C
54 °F
12 °C
60 °F
16 °C
66 °F
19 °C
76 °F
24 °C
Growing Season
The number of consecutive warm months, as derived from
average minimum monthy temperature
(1981 - 2010) cell data.
For a particular month, a 30 arcsecond cell is considered warm
if the average minimum temperature is at least 43 ° F(6 ° C).
12
months
11
10
9
8
7
6
5
4
3
2
≤ 1
month
USDA Hardiness Zone
The map is based on average annual minimum winter temperature,
divided into zones by 5 ° F increments. See
the
USDA Plant Hardiness Zone Map.
Hardiness Zone differs from December Low Temperature above,
in that it reflects the lowest temperature that might ever be experienced
at a location.
Units: degrees Fahrenheit
5a: -20 to -15
5b: -15 to -10
6a: -10 to -5
6b: -5 to 0
7a: 0 to 5
7b: 5 to 10
8a: 10 to 15
8b: 15 to 20
9a: 20 to 25
9b: 25 to 30
10a: 30 to 35
10b: 35 to 40
11a: 40 to 45
DISCLAIMER: Shapefiles of the hardiness zones for California
were purchased and downloaded from Climate Source in February, 2014.
They were subsequently modified (chopped into smaller pieces) for
display as a map background layer.
USDA Agricultural Research Service Terms of Use:
Data: Users may obtain enhanced (high resolution) official USDA Plant Hardiness GIS data in shapefile and raster grid formats from Climate Source, Inc. (www.climatesource.com/PHZM/gis_data.html), subject to Climate Source terms of use. The USDA-ARS and OSU logos must be prominently displayed on any maps derived from the GIS datasets. The data may not be altered in any way without an explicit and prominently displayed disclaimer that the map is not the official USDA Plant Hardiness Zone Map, and USDA-ARS and OSU logos must not be displayed in the modified version.
(See also
GIS Data Downloads.)
Climate Source Inc. Notice:
This product contains data from The Climate Source and is used herein by permission. Copyright (c) 2014 The Climate Source, www.climatesource.com. All Rights Reserved.
(See also
License Agreement.)
SOIL LAYERS
SSURGO SOIL DATA
from the Soil Survey Geographic (2.2) Database dated October 1, 2018.
Updated on Calflora April 17, 2019 and again on September 20, 2019.
See also
SSURGO Table Struture California is described by 18,960 mapunit records, each of which corresponds to one or more polygons.
Within each mapunit there are several soil component records. A component record has a
percent (comppct_r) attribute, indicating its relative strength within the map unit.
A component record may be associated with several chorizon records.
Each chorizon record has top depth (hzdept_r) and bottom depth (hzdepb_r) attributes specified in centimeters.
Click on the Derivation links below for more information about how the value displayed
was derived from SSURGO data.
CITATION:
Soil Survey Staff, Natural Resources Conservation Service,
United States Department of Agriculture. Soil Survey Geographic (SSURGO)
Database for California.
Available online at
NRCS Geospatial Data Gateway
Accessed 04/10/2019.
Soil Depth
Minimum depth to
the first restrictive layer
of the components of a soil map unit.
Derivation:
For 9,886 mapunit records, minimum depth was available from the
brockdepmin (minimum depth to bedrock) attribute in the muaggatt table.
For the other mapunit records, minimum depth was calculated by choosing the
deepest non-rock horizon of each component, and then averaging these numbers weighted
by the component percent.
"Soil reaction" is a numerical expression of the relative acidity or alkalinity of a soil.
...
Soils that have a pH of approximately 6 or 7 generally have the most ready availability of plant nutrients.
Derivation:
Each component record has one topmost chorizon record (where hzdept_r = 0).
pH for the mapunit was calculated by averaging the chorizon ph1to1h2o_r attribute
of these topmost horizons, weighted by the component percent.
Class
pH
Extremely acid
3.5 to 4.4
Very strongly acid
4.5 to 5.0
Strongly acid
5.1 to 5.5
Moderately acid
5.6 to 6.0
Slightly acid
6.1 to 6.5
Neutral
6.6 to 7.3
Slightly alkaline
7.4 to 7.8
Moderately alkaline
7.9 to 8.4
Strongly alkaline
8.5 to 9.0
Soil CaCO3
The maximum calcium carbonate equivalent in the components of a soil map unit.
“Calcium carbonate equivalent” is the
quantity of carbonate (CO3) in the soil expressed as CaCO3 and as a
weight percentage of the less than 2 mm size fraction.
... The availability of plant
nutrients is influenced by the amount of carbonates in the soil.
This is a result of the effect that carbonates have on soil pH and
of the direct effect that carbonates have on nutrient availability.
Derivation:
Each component record has one topmost chorizon record (where hzdept_r = 0).
CaCO3 for the mapunit was calculated by averaging the chorizon caco3_r attribute
of these topmost horizons, weighted by the component percent.
< 1 %
2.5 %
3.5 %
5.5 %
7.5 %
> 10 %
Available Water Storage
The volume of water that the soil, to a depth of 100 centimeters, can store that is available to plants. It is reported as the weighted average of all components in the map unit, and is expressed as centimeters of water.
Derivation:
Copied from the muaggatt table aws0100wta attribute.
AWS is calculated from AWC (available water capacity) which is commonly estimated as the difference between the water contents at 1/10 or 1/3 bar (field capacity) and 15 bars (permanent wilting point) tension, and adjusted for salinity and fragments.
1 cm
5 cm
10 cm
15 cm
20 cm
25 cm
Soil Salinity
as indicated by electrical conductivity.
The maximum conductivity of the components of a soil map unit.
Electrical conductivity is a measure of the concentration of water-soluble salts in soils. It is used to indicate saline soils. High concentrations of neutral salts, such as sodium chloride and sodium sulfate, may interfere with the absorption of water by plants
... [and]
may also interfere with the exchange capacity of nutrient ions...
Derivation:
Each component record has one topmost chorizon record (where hzdept_r = 0).
Electrical conductivity for the mapunit was calculated by averaging the chorizon ec_r attribute
of these topmost horizons, weighted by the component percent.
Class
Conductivity in mmhos / cm
Non-saline
0 to <2
Very slightly saline
2 to <4
Slightly saline
4 to <8
Moderately saline
8 to <16
Strongly saline
≥16
Soil Texture
Texture as used here is based on
the texture description of the major component of a soil map unit.
A typical categorization of textures is shown below
(image from the
NRCS Soil Texture Calculator).
March 11, 2023
Added the geology layer, courtesy of USGS.
June 12, 2020
The SSURGO layers Texture and Available Water Storage
were re-done with new colors.
March 1, 2020
Added ultramafic areas as a soil layer, courtesy of USGS.
September 20, 2019
The SSURGO polygons loaded last April were over optimized:
when you zoomed very close, the boundaries between polygons did not meet smoothly.
The SSURGO polygons were reloaded on September 20 without this over optimization problem.
Soil background layers will now appear on maps all the way out to zoom level 9.
VIDEO: Overview
will appear at the end of each creek or river.
When you click on the icon, you see the name of the creek or river, and the name
of the stream that the creek or river flows into.
.
