Generalized Provisional
Seed Zones for Native Plants
Andy Bower
Brad St. Clair
Vicky Erickson
Great Basin Native Plant Selection and Seed
Increase Project
Annual Meeting
February 22, 2011 – Salt Lake City
Why are Seed Zones important?
• Use of appropriate plant materials is a core
component of successful restoration projects
• The key to identifying appropriate plant materials
(e.g. seeds) lies in understanding the genetics of
adaptation
• Molecular markers reflect demographic history NOT
the effects of selection
• “Selectively neutral” molecular markers are not
appropriate for determining seed zones
Seed zones for Forest Trees
• First seed movement guidelines
in 1939 by U.S. Forest Service in
response to plantation failures
– 100 miles north or south of planting site
– 1,000 feet in elevation
– consideration given to unusual climatic,
topographic or soil conditions
Seed Zones for Small Native Plants
• To date, very few seed zones
have been delineated for
shrubs, grasses or forbs
• But we know that there is
ecotypic variation
Mather
Stanford
Native To
Timberline
Potentilla glandulosa from three different elevations
planted at three different elevations
(from Clausen, Keck and Hiesey 1940)
Stanford
Mather
Grown At
Timberline
Common Garden Studies
• Common garden studies (although cost and time
intensive) are the only way to assess variation in
adaptive traits
• In 2002 the Interagency Native Plant Materials
Report to Congress (USDI and USDA) noted the
value of common garden studies and genetic
analysis for delineating seed zones for maintaining
diverse and well-adapted plant populations
What to do for species with no info
available on genetic variation?
•
•
•
•
•
USDA plant hardiness zones
Forest tree seed zones
Watershed / elevation band
Climate “matching”
Ecoregions
–Bailey,Omernick, level III, level IV
• PAR’s
USDA Plant Hardiness Zones
(min winter temperatures)
Use general forest tree seed zones
Use climate data to match source and
planting site environments
PRISM (http://www.prism.oregonstate.edu/)
Ecoregions (Omernick’s level III)
http://www.epa.gov/naaujydh/pages/ecoregions/level_iii.htm
Use combination of ecoregions and temperature
Building Provisional Seed Zones
• Independent of genetics
–Intended for species with no specific
genetic data available
• Provisional seed zones are a “starting
point”
• Local and species specific knowledge
important in adjusting zones for use
Methods
• High resolution (800m x 800m) climate data
obtained from PRISM
(www.prism.oregonstate.edu)
• 30-year climate normals (1970-2000)
– Minimum temp (trees & woody plants)
– Maximum temp (grasses & herbaceous plants)
– Annual precipitation
• GIS used to combine temperature & precipitation
into zones of similar climate
Winter Min. Temp. 5o F. Bands
Data obtained from www.prism.oregonstate.edu
Avg Max. Temp. 10o F Bands
Data obtained from www.prism.oregonstate.edu
Annual Precipitation (6 bands)
Data obtained from www.prism.oregonstate.edu
Climate Based Provisional Seed Zones
Winter Min Temp / Annual Precip
Climate Based Provisional Seed Zones
Average Max Temp / Annual Precip
Results
• 68 minimum temp / precipitation bands
• 28 maximum temp / precipitation bands
Region
Zone
Eastern U.S.
Min. temp./precip
# zones # polygons Mean Polygon
Area (km2)
45
7024
728.3
Area Std.
Dev.
12494.8
Western U.S. Min. temp./precip
63
26673
141.9
3008.8
Eastern U.S.
Max. temp./precip
23
4222
1256.7
32484.5
Western U.S. Max. temp./precip
27
10674
367.2
10260.0
Omernick’s Level III Ecoregions
http://www.epa.gov/naaujydh/pages/ecoregions/level_iii.htm
Seed Zone + Ecoregion
Winter Min Temp / Annual Precip
Seed Zone + Ecoregion
Average Max Temp / Annual Precip
“But That’s Too
Many Zones!”
• 15 Level III
Ecoregions
• 24 Max Temp
Zones
• 50 Min Temp
Zones
Bluebunch
Wheatgrass
(Pseudoroegneria
spicata)
•114 Locations
•10 max temp zones
•16 min temp zones
•12 Level III
ecoregions
Seed Zones vs. Ecoregions
(For Bluebunch Wheatgrass)
Max Temp Zone
# Loc'ns
> 60 Deg. / 14 - 24 in.
1
60 - 70 Deg. / 10 - 14 in.
3
60 - 70 Deg. / 14 - 24 in.
20
60 - 70 Deg. / 24 - 48 in.
10
60 - 70 Deg. / 48 - 100 in.
3
70 - 80 Deg. / < 10 in.
6
70 - 80 Deg. / 10 - 14 in.
26
70 - 80 Deg. / 14 - 24 in.
34
70 - 80 Deg. / 24 - 48 in.
5
80 - 90 Deg. / 10 - 14 in.
2
92% in 6 zones
82% in 4 zones
Min Temp Zone
# Loc'ns
5 to 10 / 10 - 14 in.
1
5 to 10 / 14 - 24 in.
2
10 to 15 / 14 - 24 in.
7
10 to 15 / 24 - 48 in.
2
15 to 20 / < 10 in.
1
15 to 20 / 10 - 14 in.
13
15 to 20 / 14 - 24 in.
16
15 to 20 / 24 - 48 in.
8
15 to 20 / 48 - 100 in.
1
20 to 25 / < 10 in.
5
20 to 25 / 10 - 14 in.
17
20 to 25 / 14 - 24 in.
24
20 to 25 / 24 - 48 in.
4
20 to 25 / 48 - 100 in.
2
25 to 30 / 14 - 24 in.
6
25 to 30 / 24 - 48 in.
1
91% in 9 zones
83% in 7 zones
Level III Ecoregion
# Loc'ns
Blue Mountains
39
Cascades
1
Central Basin and Range
7
Columbia Plateau
26
E. Cascades Slopes & Foothills
5
Idaho Batholith
1
Klamath Mountains
1
Middle Rockies
2
North Cascades
1
Northern Basin and Range
21
Northern Rockies
2
Snake River Plain
4
93% in 6 zones
85% in 4 zones
Provisional Seed Zone Caveats
• Microsites must be appropriate for the
species (e.g., use riparian species on
riparian sites, not dry upland sites)
• Seed zones differ by species, so local
knowledge is important
• Research needed to construct seed
movement guidelines based on actual
genetic data
Validation With Common Gardens
Species
Distribution Sampled
Roemer's fescue
California oatgrass
Prairie junegrass
Blue wildrye
Bluebunch wheatgrass
Sandberg's bluegrass
Mountain Brome
California brome
Tapertip onion
Oceanspray
Bigdeer vetch
Indian ricegrass
Fernleaf biscuitroot
Broadleaf lupine
Antelope bitterbrush
Alder
Festuca idahoensis
Danthonia californica
Koleria macrantha
Elymus glaucus
Pseudoroegneria spicata
Poa secunda
Bromus marginatus
Bromus carinatus
Allium acuminatum
Holodiscus discolor
Lotus crassifolius
Acnatherum hymenoides
Lomatium dissectum
Lupinum latifolius
Purshia tridentata
Alnus rubra
W. Oregon & Washington
W. Oregon
Colubia Plateau
NE Oregon
Great Basin & Columbia Plateau
Great Basin & Columbia Plateau
NE Oregon
W. Oregon
Great Basin
W. Oregon & Washington
OR Cascades & Coast Range
Great Basin & Colorado Plateau
Oregon and Idaho
W. Oregon & Washington
E. Oregon & Washington
W. Oregon & Washington
Douglas-fir
Pseudotsuga menziesii
W. Oregon & Washington
Acknowledgements
• Matt Horning, RC Johnson, Randy
Johnson, Dale Darris
• Ken Vance-Borland
http://www.fs.fed.us/wwetac/threat_map/SeedZones_Intro.html