Vegetation Classification and Mapping Program, California Department of Fish and Wildlife
20190205
Vegetation - Knoxville Wildlife Area [ds2812]
vector digital data
http://ftp.wildlife.ca.gov/BDB/GIS/BIOS/Public_Datasets/2800_2899/ds2812.zip
https://www.wildlife.ca.gov/Data/BIOS
The California Department of Fish and Wildlife (Department) Vegetation Classification and Mapping Program (VegCAMP) created a fine-scale vegetation classification and map of the southern addition to the Departments Knoxville Wildlife Area (WA), Napa County, California following State Vegetation Survey, Federal Geographic Data Committee (FGDC), and National Vegetation Classification (NVC) Standards (Grossman et al 1998). The vegetation classification was derived from data collected in the field following the Combined Rapid Assessment and Relevé Protocol during the periods November 18–20, 2013 and April 28–May 1, 2014. Vegetation polygons were drawn using heads-up manual digitizing using the 2011 Napa County 30-cm resolution color infrared (CIR) imagery as the base imagery. Supplemental imagery included National Agricultural Imagery Program (NAIP) true color and CIR 1-meter resolution data from 2009–2012, BING imagery, and current and historical imagery from Google Earth. The minimum mapping unit (MMU) is 1 acre, with the exception of wetland types, which have an MMU of 1/2 acre. Ponds, riparian types, and the one vernal pool on the WA that were visible on the imagery were mapped regardless of size, and streams were generally mapped if greater than 10 m wide (narrower portions may have been mapped to maintain the continuity of the streams). Mapping is to the NVC hierarchy association, alliance, or group level based on the ability of the photointerpreters to distinguish types based on all imagery available and on the field data. Both the existing (northern) and new addition (southern) portions of the Knoxville WA were mapped in 2002 as part of the Napa County vegetation map (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=14660). The 2002 map is at a coarse thematic resolution (alliance through macrogroup level) and vegetation in portions of the WA has changed since the 2004 Rumsey Fire, necessitating this map update. We have produced an updated version of the KWA portion of the 2002 map layer that uses the same spatial data, but added a crosswalk to the current classification and the upper levels of the current hierarchy. This map layer is included in the downloaded dataset for this map and an expanded metadata report for that crosswalk can be found at https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164825.
The purpose of the classification and vegetation map is to aid in the development of a management plan for the Department‘s Knoxville Wildlife Area. The vegetation classification and mapping provide an inventory of habitat types, and a measure of the extent of each type on the property, for use in assessing the biological resources present and determining appropriate management strategies.
Field Sampling Methods
Relevé samples were collected from 22 vegetation stands and Rapid Assessment (RA) samples were collected from 46 vegetation stands from November 18–20, 2013 and April 28–May 1, 2014 following the Combined Relevé and Rapid Assessment Protocol (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18599&inline) and using the Combined Relevé and Rapid Assessment form (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18598&inline). Relevés were used for herbaceous vegetation and include the absolute cover of all species within a 100 square meter plot. Rapid assessments were used for vegetation types characterized by a cover of at least 10 percent trees or shrubs; they include the absolute cover of 10–20 of the most common or characteristic species in the entire stand (i.e., a plotless sample). Reconnaissance samples were collected for 122 stands of vegetation. A subset of the Relevé and Rapid Assessment data is collected during a Reconnaissance (Recon form found in Appendix C of report Vegetation Map and Classification of Knoxville Wildlife Area, Napa County (2014) (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164824)). A list of all plant species recorded during field data collection can be found in Appendix D of report Vegetation Map and Classification of Knoxville Wildlife Area, Napa County (2014) (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164824).
Sample point locations were collected with GPS-enabled data recording devices and are stored in a geodatabase maintained by VegCAMP. Relevé and Rapid Assessment data were entered into VegCAMPs MS Access database, which is available from VegCAMP. The Rapid Assessment and Relevé data include the date of sampling, GPS location, environmental characteristics of the sampled stands (microtopography, substrate, soil texture, slope, aspect, ground surface characteristics, disturbance type and intensity), vegetation structure (tree, shrub, and herb cover and height, total vegetation cover), cover by species, site history, and the Alliance and Association. Additionally, four digital photos taken in the cardinal directions from each Relevé or Rapid Assessment location are available from VegCAMP. These data and field photos can serve as a baseline for monitoring future vegetation change. The Reconnaissance data provide observational notes on stand composition and environmental attributes at specific GPS locations in the landscape, and are sometimes associated with photos. The primary use of Reconnaissance data is to aid in mapping.
Vegetation Classification Methods
The classification is based largely on existing vegetation types described in the Manual of California Vegetation (Sawyer et al. 2009), but includes new provisional types which are supported by Buck-Diaz et al. 2012, Evens and Kentner 2006, and this project. The Relevé and RA data collected in 2013 and 2014 (68 surveys total) were used to create the vegetation and map classification for the Knoxville WA. These data were analyzed using multivariate cluster analysis, performed by PC-ORD version 6 software. The cluster analysis was based on abundance (cover values) converted to seven different classes using the following modified Braun-Blanquette (1932) cover categories: 1 equal to or less than 1 percent, 2 = 1–5 percent, 3 equal to or greater than 5–15 percent, 4 equal to or greater than 15–25 percent, 5 equal to or greater than 25–50 percent, 6 equal to or greater than 50–75 percent, 7 equal to or greater than 75 percent. For the analysis, VegCAMP used the Sorensen distance measure and flexible beta linkage method at -0.25 (McCune and Grace 2002). Floristic data collected in 103 reconnaissance samples were used to refine and validate the final classification for the map.
Naming conventions for vegetation types follow the National Vegetation Classification System (Grossman et al. 1998) and the Manual of California Vegetation, 2nd edition (Sawyer et al. 2009). An association is defined by a group of samples that has similar dominant and characteristic species in the overstory, along with other important or indicator species, which are distinctive in a particular environmental setting. A set of similar associations is grouped hierarchically to the next higher level in the classification, the alliance. Alliances can then be nested under groups, and groups nested under macrogroups. For this map, vegetation was mapped to the association level if possible, but some polygons were mapped only to alliance. The Hierarchical Field and Mapping Key used to classify the vegetation types for this project can be found in Appendix E of report Vegetation Map and Classification of Knoxville Wildlife Area, Napa County (2014) (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164824).
Delineation Rules and Map Attributes
The vegetation map was delineated according to the following rules:
Minimum Mapping Unit (MMU) and minimum width:
1 acre for typical vegetation types
½ acre for special vegetation types (e.g., localized types)
No MMU for cattle ponds
10 meter width for linear features
Polygon cover class breaks:
3 acre MMU for cover class break in the overstory vegetation cover (i.e., when the adjacent vegetation is of the same mapping unit, but the cover class is different)
5 acre MMU for cover class break in the understory vegetation cover
Delineation: All polygons were drawn at a scale of 1:800 to 1:3500
Additional information, including a Key to Identification of All Stands of Vegetation Sampled or Encountered in the Field can be found in the metadata report, Vegetation Map and Classification of Knoxville Wildlife Area, Napa County (2014) (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164824).
Field Verification
Field verification has not yet been completed for this map, as of January 2019. Although some areas have burned since mapping was completed in 2014, the majority of the WA lands have not burned, preserving our objective to complete accuracy assessment for this map as time and funding allow.
New Alliances and Associations (for 2018 BIOS)
Since generating the map in 2014, some alliances and associations have changed, often expanded, and the current NVCS type does not exactly match the map class originally used. In each case below, the NVCS type is followed by the corresponding 2014 map class in parenthesis:
-“Allium spp. - Streptanthus spp. - Hesperolinon spp. Serpentinite Provisional Alliance” (“Allium falcifolium-Eriogonum spp.-Streptanthus spp. Provisional Semi-natural Stands”)
-“Ceanothus (oliganthus, tomentosus) Alliance” ("Ceanothus oliganthus Alliance")
-“Leymus cinereus - Leymus triticoides Alliance” (“Leymus triticoides Alliance”)
-“Thermopsis californica - Bromus carinatus - Annual Brome Association” (“Thermopsis californica Provisional Association”)
-“Corethrogyne filaginifolia - Eriogonum (elongatum, nudum) Alliance” (“Eriogonum (elongatum, nudum) Provisional Alliance”)
-“Eschscholzia (californica) - Lupinus (nanus) Alliance” (“Eschscholzia (californica) Alliance”)
-“Nassella spp. - Melica spp.” (“Melica (californica, torreyana) Provisional Alliance”)
-“Nassella spp. - Melica spp.” (Nassella pulchra Alliance)
Additionally, the following name change of species occurred since 2014, resulting in a corresponding change in alliance name. The current NVCS name is followed in parenthesis by the map class utilized in the 2014 map:
-"Hesperocyparis sargentii Alliance" ("Callitropsis sargentii Alliance")
Notes on Rarity Rankings (for 2018 BIOS)
The NVCS type “Nassella spp. - Melica spp. Alliance” has been assigned to two map classes utilized in 2014: “Melica (californica, torreyana) Provisional Alliance” and “Nassella pulchra Alliance”. The new expanded alliance is not rare, with global and state ranks of G4 and S4, respectively, yet all currently-known associations within this alliance are considered rare at this time (including those that would be closely analogous to the above original map classes). As such, please note that, while broadly taken together this type is not rare, each occurrence of this type delineated in the map would in fact be rare when individually assessed at a finer scale of classification.
Several associations within this map are assumed to be rare at this time, however their exact global and state rarity rankings are yet to be determined and vetted. Please consider these types to have state ranks of S3 or lower, as per our current understanding of their distribution and/or threat impacts:
-"Adenostoma fasciculatum - Heteromeles arbutifolia / Melica torreyana"
-"Ceanothus oliganthus - Adenostoma fasciculatum"
-"Quercus berberidifolia - Ceanothus oliganthus"
-"Quercus durata - Adenostoma fasciculatum"
-"Quercus lobata - Quercus wislizeni"
-"Umbellularia californica - Quercus wislizeni"
Rarity ranks are subject to change due to changing threats and trends and as ranking methodologies are further refined. At this time, ranks are updated using the NatureServe Conservation Status Assessments Rank Calculator Version 3.186 and the ranks for this map are current as of January 22, 2019. Please check CDFWs Natural Communities page for the most up-to-date rarity ranks (https://www.wildlife.ca.gov/Data/VegCAMP/Natural-Communities).
References
Buck, J., and S. Batiuk. 2012. Vegetation Alliances and Associations of the Great Valley Ecoregion, California. California Native Plant Society, Sacramento, CA. (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=64011&inline).
California Department of Fish and Wildlife, Vegetation Classification and Mapping Program. Knoxville Wildlife Area 2002 Vegetation Map Crosswalked to the Knoxville Wildlife Area 2014 Southern Unit Map Classification. CDFW, January 2019. (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164825).
California Department of Fish and Wildlife, Vegetation Classification and Mapping Program. Vegetation Map and Classification of Knoxville Wildlife Area, Napa, County, California. CDFW, January 2019. (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=164824).
Evens, J., and E. Kentner. 2006. Classification of vegetation associations from the Mount Tamalpais Watershed, Nicasio Reservoir, and Soulajule Reservoir in Marin County, California. California Native Plant Society, Sacramento, CA. (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=16314).
Grossman, D. H., K. Goodin, M. Anderson, P. Bourgeron, M. T. Bryer, R. Crawford, L. Engelking, D. Faber-Langendoen, M. Gallyoun, S. Landaal, K. Metzler, K. D. Patterson, M. Pyne, M. Reid, L. Sneddon, and A. S. Weakley. 1998. International classification of ecological communities: Terrestrial vegetation of the United States. The Nature Conservancy. Arlington, VA.
McCune, B. and J. B. Grace. 2002. Analysis of Ecological Communities. MjM Software, Gleneden Beach, OR. (www.pcord.com).
Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A Manual of California Vegetation, 2nd Edition. California Native Plant Society. Sacramento, CA. (https://vegetation.cnps.org).
USDA Forest Service. Calveg System. (https://www.fs.fed.us/r5/rsl/projects/classification/system.shtml)
Thorne, J., J. Kennedy, J. Quinn, M. McCoy, T. Keeler-Wolf, and J. Menke. "A Vegetation Map of Napa County Using the Manual of California Vegetation Classification and Its Comparison to Other Digital Vegetation Maps." Madrono, Vol. 51, No.4, pp. 343-363, 2004. (https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=14660).
November 2013
May 2014
ground condition
As needed
-122.342529
-122.224999
38.801682
38.696007
ISO 19115 Topic Category
biota
ISO 19115 Topic Category
environment
None
vegetation
None
Knoxville Wildlife Area
Napa County
California
DFW only until Management Plan is made public.
DFW appreciates learning how our datasets are being used so that we can leverage support for classifying and mapping new areas and let users know of any updates. Please contact Diana Hickson by email or by phone at 916-327-5956.License: This work is licensed under Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). Using the citation standards recommended for BIOS datasets (https://www.wildlife.ca.gov/Data/BIOS/Citing-BIOS) satisfies the attribution requirements of this license.Disclaimer: The State makes no claims, promises, or guarantees about the accuracy, completeness, reliability, or adequacy of these data and expressly disclaims liability for errors and omissions in these data. No warranty of any kind, implied, expressed, or statutory, including but not limited to the warranties of non-infringement of third party rights, title, merchantability, fitness for a particular purpose, and freedom from computer virus, is given with respect to these data.
California Department of Fish and Wildlife
Diana Hickson
Senior Biologist, Vegetation Classification and Mapping Program
mailing and physical
1807 13th Street, Suite 202
Sacramento
CA
95811
US
(916) 327-5956
(916) 324-0475
Diana.Hickson@wildlife.ca.gov
California Department of Fish and Wildlife
Diana Hickson
Senior Biologist, Vegetation Classification and Mapping Program
mailing and physical
1807 13th Street, Suite 202
Sacramento
CA
95811
US
(916) 327-5956
(916) 324-0475
Diana.Hickson@wildlife.ca.gov
Vegetation Classification and Mapping Program (VegCAMP), Department of Fish and Wildlife.
Version 6.2 (Build 9200) ; Esri ArcGIS 10.6.1.9270
Vector
GT-polygon composed of chains
1631
NAD 1983 California Teale Albers
34.0
40.5
-120.0
0.0
0.0
-4000000.0
coordinate pair
0.0001
0.0001
meter
D North American 1983
GRS 1980
6378137.0
298.257222101
ds2812
OBJECTID
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
SHAPE
Feature geometry.
Esri
Coordinates defining the features.
NVCSName
The standardized name of the vegetation description used in the National Vegetation Classification System (see http://usnvc.org/). Since the NVCS does not have categories for human land use or otherwise unvegetated land, those descriptions were drawn from the California Wildlife Habitat Relationship.
NVCSLevel
The standardized level of the vegetation description used in the National Vegetation Classification System (see http://usnvc.org/).
MapClass
The finest level of vegetation type mapped (alliance, association, group or macrogroup); or land use for polygons that are not natural vegetation, per the mapping classification.
MapClassCode
Code for each vegetation type mapped. MapClassCodes are defined in the MapClass field.
Heterogeneity
The measure of uniformity of the vegetation type, cover class and size class within the polygon. A low heterogeneity is desirable.
1
Low, <5% heterogeneous
2
Moderate, 5–40% heterogeneous
3
High, >40% heterogeneous
ConifCover
The cover of conifer trees in the polygon.
0
none visible
1
trace–0.9%
5
1-9.9%
15
10-19.9%
25
20-29.9%
35
30-39.9%
45
40-49.9%
55
50-59.9%
65
60-69.9%
75
70-79.9%
85
80-89.99%
95
90-100%
<null>
used for water features (ponds and streams)
HdwdCover
The cover of hardwood trees in the polygon.
none visible
0
trace-.9%
1
1-9.9%
5
10-19.9%
15
20-29.9%
25
30-39.9%
35
40-49.9%
45
50-59.9%
55
60-69.9%
65
70-79.9%
75
80-89.99%
85
90-100%
95
<null>
used for water features (ponds and streams)
TreeCover
The cover of all trees (conifer and hardwood) in the polygon.
none visible
0
trace-.9%
1
1-9.9%
5
10-19.9%
15
20-29.9%
25
20-29.9%
25
30-39.9%
35
40-49.9%
45
50-59.9%
55
60-69.9%
65
70-79.9%
75
80-89.99%
85
90-100%
95
<null>
used for water features (ponds and streams)
ShrubCover
The cover of all shrubs in the polygon.
0
none visible
trace-.9%
1
1-9.9%
5
10-19.9%
15
20-29.9%
25
30-39.9%
35
40-49.9%
45
50-59.9%
55
60-69.9%
65
70-79.9%
75
80-89.99%
85
90-100%
95
used for water features (ponds and streams)
<null>
HerbCover
Herbaceous cover.
0
0%
1
<2%
2
2-9%
3
10-39%
4
40-59%
5
60-100%
99
can't determine
NonNative_Plants
The presence of non-native plants in the polygon.
0
Not Visible, no visible non-native cover
1
Low, total non-native cover is <33% of total vegetation cover
2
Medium, total non-native cover is 33–66% of total vegetation cover
3
High, total non-native cover is >66% of total vegetation cover
Roads_Trails
The presence of roads or trails in the polgyon.
0
Not visible, there are no visible roads or trails in the polygon, i.e. the polygon is “whole”
1
Low, roads or trails bisect the polygon, so that from 2/3 to just below the entire polygon is "whole"
2
Medium, roads or trails bisect the polygon, so that 1/3–2/3 of the polygon is “whole”
3
High, roads or trails bisecting the polygon, so that <1/3 of the polygon is “whole”
OtherImpact
Impacts observable in the imagery.
OHV Activity
OHV Activity
Disking/grading
Disking/grading
Riparian
Riparian modification
Development
Development
Erosion/runoff
Erosion/runoff
Ungulate trails
Ungulate trails
none
none
Level_OtherImpact
Subjective determination of the level of any impact recorded in the "OtherImpact"
0
Not Visible
1
Low
2
Medium
3
High
Comments
Text field for additional information.
UID
Unique identifier for each polygon.
FireEvidence
Evidence of recent fire.
Yes
dead snags or other evidence of a recent fire are apparent on the imagery, or field data indicate evidence of fire
No
no evidence is evident, but likely would be evident if the polygon had burned
Unknown
the vegetation type would not show any photointerpretable indication of recent fire; herbaceous stands or shrub stands that don’t leave dead standing stems and that resprout very quickly are examples
DBH
The diameter at breast height (DBH) of the trees within the polygon, using California Wildlife Habitat Relationships classes.
T1
<1” dbh
T2
1-6” dbh
T3
6-11” dbh
T4
11-24” dbh
T5
>24” dbh
T6
multi-layered (T3 or T4 layer under T5, >60% cover)
CalVegName
A crosswalk to the CalVeg vegetation system. Note that there may be a one-to-many relationship between CalVeg and NVCS. See http://www.fs.usda.gov/detail/r5/landmanagement/resourcemanagement/?cid=stelprdb5347192.
CalVegCode
A crosswalk to the CalVeg vegetation system. Note that there may be a one-to-many relationship between CalVeg and NVCS. See http://www.fs.usda.gov/detail/r5/landmanagement/resourcemanagement/?cid=stelprdb5347192.
CWHRType
A crosswalk to the California Wildlife Habitat Relationships system. Note that there is usually a one-to-many relationship between CWHR and NVCS. See http://www.dfg.ca.gov/biogeodata/cwhr/.
CWHRCode
A crosswalk to the California Wildlife Habitat Relationships system. Note that there is usually a one-to-many relationship between CWHR and NVCS. See http://www.dfg.ca.gov/biogeodata/cwhr/.
GlobalRank
The global rarity rank of the plant community mapped (only for polygons mapped to the alliance level). G1: Fewer than 6 viable occurrences and/or 2000 acres worldwide; G2: 6–20 viable occurrences and/or 2000–10,000 acres worldwide; G3: 21–100 viable occurrences and/or 10,000–50,000 acres worldwide; G4: Greater than 100 viable occurrences and/or greater than 50,000 acres worldwide; G5: Community demonstrably secure due to secure worldwide abundance. See: http://www.natureserve.org/sites/default/files/publications/files/natureserveconservationstatusmethodology_jun12_0.pdf.
StateRank
The state rarity rank of the plant community mapped (only for polygons mapped to the alliance level). S1: Fewer than 6 viable occurrences and/or 2000 acres statewide; S2: 6–20 viable occurrences and/or 2000–10,000 acres statewide; S3: 21–100 viable occurrences and/or 10,000–50,000 acres statewide; S4: Greater than 100 viable occurrences and/or greater than 50,000 acres statewide; S5: Community demonstrably secure due to secure statewide abundance. See: http://www.natureserve.org/sites/default/files/publications/files/natureserveconservationstatusmethodology_jun12_0.pdf.
Rare
Rarity of the vegetation type. Alliances and associations with state ranks of S1-S3 are considered rare.
Yes
Rare
No
Not Rare
CaCode
California Natural Community Codes - unique code assigned to alliances and associations.
NVCSAlliance
The standardized name for the alliance within the National Vegetation Classification System. See http://usnvc.org/
NVCSGroup
The standardized name for the group within the National Vegetation Classification System. See http://usnvc.org/.
NVCSMG
The standardized name for the macrogroup within the National Vegetation Classification System. See http://usnvc.org/.
Acres
GIS-calculated area measurements of each mapped polygon.
Hectares
GIS-calculated area measurements of each mapped polygon.
SHAPE_Length
Length of feature in internal units.
Esri
Positive real numbers that are automatically generated.
SHAPE_Area
Area of feature in internal units squared.
Esri
Positive real numbers that are automatically generated.
California Department of Fish and Wildlife
Diana Hickson
Senior Biologist, Vegetation Classification and Mapping Program
mailing and physical
1807 13th Street, Suite 202
Sacramento
CA
95811
US
(916) 327-5956
(916) 324-0475
Diana.Hickson@wildlife.ca.gov
See access and use constraints information.
20220722
California Department of Fish and Wildlife
Diana Hickson
Senior Biologist, Vegetation Classification and Mapping Program
mailing and physical
1807 13th Street, Suite 202
Sacramento
CA
95811
US
(916) 327-5956
(916) 324-0475
Diana.Hickson@wildlife.ca.gov
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time