Clover Species Maps

Defining the regions within the USA where the various fall dormancy (FD) and winter survival index (WSI) alfalfa cultivar types can be successfully used is an important marketing and management application of GIS technologies. These maps provide a guide for cultivar selection decisions and for identifying areas for conducting further field evaluations to validate and/or revise these maps.

Low winter temperatures limit the northern range of the FD and WSI types, while other climate and soil factors also combine to define optimal cultivar characteristics.

Agronomic field trials have been the standard evaluation technique for selecting cultivars, but extrapolation of information from one site to another for these types of trials has always been problematic. By developing suitability zone maps, based on our best knowledge of cultivar characteristics, field-based evaluation can make more efficient use of available testing resources. Using these techniques and technologies, the limited number of field trials can be extended across the USA and contribute to the global suitability information contained in the quantitative tolerances tables and function.

 Drop-down menu for Fall Dormancy Level

Drop-down menu for Winter Survival Index

Climate

  Jan Tmin

  Jul Tmax

  Ann Precipitation

  Combined

Soil

  pH

  Drainage

  Salinity

  Combined

Climate and Soil Combined

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

Image

(Alsike clover generalized adaptation and common use map.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database. The procedure used to produce these suitability maps is described below.

Suitability curves were developed for each clover species for three climate variables (average annual precipitation, average July maximum temperature, and average annual extreme low temperature) and three soil variables (drainage class, pH, and salinity). For each variable and each species, the curves were fit using estimated yield data across the full range of values for the given variable.  

The coefficients for the model equations were applied to spatial data layers representing each climate and soil variable, resulting in spatial outputs of percent yield for each of the clover species and each climate and soil variable. The percent yield layers were then classified into four suitability classes, as follows: 

100%-75% - Suitable
75%-50%  - Moderately suitable
50%-25%  - Marginally suitable
25-0%    - Not suitable

Finally, three "hybrid" suitability layers were produced for each clover species based on combinations of 1) the three climate variables, 2) the three soil variables, and 3) all six climate and soil variables together.  These combined suitability layers were created by selecting for each location the lowest suitability value of the included variables, with the idea that the overall suitability for a species will be limited by the most restrictive factor. 

Data sources
----------------
Climate data: 800m PRISM 30-year normals for years 1981-2010 (PRISM Climate Group, Oregon State University, accessed 2018-01-17)

Soils data:  NRCS STATSGO (Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. U.S. General Soil Map (STATSGO2). Available online. Accessed 2018-01-10)

Quantitative Tolerances GIS-based Maps

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

State Maps

Hawaii

Climate Factors	Soil Factors	Combined Factors
Minimum temperature Image	pH Image	Climate and Soil Image
Maximum temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Oregon

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

Image

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database. The procedure used to produce these suitability maps is described below.

Suitability curves were developed for each clover species for three climate variables (average annual precipitation, average July maximum temperature, and average annual extreme low temperature) and three soil variables (drainage class, pH, and salinity). For each variable and each species, the curves were fit using estimated yield data across the full range of values for the given variable.  

The coefficients for the model equations were applied to spatial data layers representing each climate and soil variable, resulting in spatial outputs of percent yield for each of the clover species and each climate and soil variable. The percent yield layers were then classified into four suitability classes, as follows: 

Finally, three "hybrid" suitability layers were produced for each clover species based on combinations of 1) the three climate variables, 2) the three soil variables, and 3) all six climate and soil variables together.  These combined suitability layers were created by selecting for each location the lowest suitability value of the included variables, with the idea that the overall suitability for a species will be limited by the most restrictive factor. 

Data sources
----------------
Climate data: 800m PRISM 30-year normals for years 1981-2010 (PRISM Climate Group, Oregon State University, http://prism.oregonstate.edu, accessed 2018-01-17)

Soils data:  NRCS STATSGO (Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. U.S. General Soil Map (STATSGO2). Available online at https://sdmdataaccess.sc.egov.usda.gov. Accessed 2018-01-10.

QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

State Maps

Alaska

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Hawaii

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Oregon

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

 Suitability curves were developed for each clover species for three climate variables (average annual precipitation, average July maximum temperature, and average annual extreme low temperature) and three soil variables (drainage class, pH, and salinity). For each variable and each species, the curves were fit using estimated yield data across the full range of values for the given variable.  

The coefficients for the model equations were applied to spatial data layers representing each climate and soil variable, resulting in spatial outputs of percent yield for each of the clover species and each climate and soil variable. The percent yield layers were then classified into four suitability classes, as follows: 

100%-75% - Suitable
75%-50%  - Moderately suitable
50%-25%  - Marginally suitable
25-0%    - Not suitable

Finally, three "hybrid" suitability layers were produced for each clover species based on combinations of 1) the three climate variables, 2) the three soil variables, and 3) all six climate and soil variables together.  These combined suitability layers were created by selecting for each location the lowest suitability value of the included variables, with the idea that the overall suitability for a species will be limited by the most restrictive factor. 

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Image

Berseem clover primary use areas as a summer or winter annual.

Source: Clark, Andy (ed.). 2007. Berseem Clover. In: Managing Cover Crops Profitably, 3rd ed. Sustainable Agriculture Network, Beltsville, MD.

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

The Contiguous USA

Click on the thumbnail image to view a larger map.

  QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Click on the thumbnail image to view a larger map.

QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Click on the thumbnail image to view a larger map.

QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Click on the thumbnail image to view a larger map.

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	Climate and Soil
Maximum Temperature Image	Drainage Image	All Soil
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

Image

(Crimson clover adaptation and use map.)

(Crimson clover SARE cover crop map. Source: Managing Cover Crops Profitably, 3rd Ed., Sustainable Agriculture Research & Education.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

Quantitative Tolerances GIS-based Maps

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

State Maps

Alaska

Climate Factor	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Hawaii

Climate Factor	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Oregon

Climate Factor	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	All Climate and Soil
Maximum Temperature Image	Drainage Image	All Soil
Precipitation Image	Salinity Image	All Climate

Click on the thumbnail image to view a larger map.

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	All Climate and Soil
Maximum Temperature Image	Drainage Image	All Soil
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	All Climate and Soil
Maximum Temperature Image	Drainage Image	All Soil Factors
Precipitation Image	Salinity Image	All Climate

Click on the thumbnail image to view a larger map.

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

Image

(Kura clover adaptation and use map.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

Quantitative Tolerances GIS-based Maps

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

State Maps

Alaska

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Hawaii

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Oregon

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

 QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil
Precipitation Image	Salinity Image	All Climate

Click on the thumbnail image to view a larger map.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database. The procedure used to produce these suitability maps is described below.

Suitability curves were developed for each clover species for three climate variables (average annual precipitation, average July maximum temperature, and average annual extreme low temperature) and three soil variables (drainage class, pH, and salinity). For each variable and each species, the curves were fit using estimated yield data across the full range of values for the given variable.  

The coefficients for the model equations were applied to spatial data layers representing each climate and soil variable, resulting in spatial outputs of percent yield for each of the clover species and each climate and soil variable. The percent yield layers were then classified into four suitability classes, as follows: 

100%-75% - Suitable
75%-50%  - Moderately suitable
50%-25%  - Marginally suitable
25-0%    - Not suitable

QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Finally, three "hybrid" suitability layers were produced for each clover species based on combinations of 1) the three climate variables, 2) the three soil variables, and 3) all six climate and soil variables together.  These combined suitability layers were created by selecting for each location the lowest suitability value of the included variables, with the idea that the overall suitability for a species will be limited by the most restrictive factor. 

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

Image

(Red clover adaptation and use map.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

Quantitative Tolerances GIS-based Maps

The contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

State Maps

 Alaska

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Hawaii

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

 Oregon

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database. The procedure used to produce these suitability maps is described below.

Suitability curves were developed for each clover species for three climate variables (average annual precipitation, average July maximum temperature, and average annual extreme low temperature) and three soil variables (drainage class, pH, and salinity). For each variable and each species, the curves were fit using estimated yield data across the full range of values for the given variable.  

The coefficients for the model equations were applied to spatial data layers representing each climate and soil variable, resulting in spatial outputs of percent yield for each of the clover species and each climate and soil variable. The percent yield layers were then classified into four suitability classes, as follows: 

100%-75% - Suitable
75%-50%  - Moderately suitable
50%-25%  - Marginally suitable
25-0%    - Not suitable

Finally, three "hybrid" suitability layers were produced for each clover species based on combinations of 1) the three climate variables, 2) the three soil variables, and 3) all six climate and soil variables together.  These combined suitability layers were created by selecting for each location the lowest suitability value of the included variables, with the idea that the overall suitability for a species will be limited by the most restrictive factor. 

Quantitative Tolerances Gis-based Maps

The contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	All Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

QUANTITATIVE TOLERANCES GIS-BASED MAPS

The Contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature  Image	pH Image	All Climate and Soil
Maximum Temperature Image	Drainage Image	All Soil
Precipitation Image	Salinity Image	All Climate Image

Click on the thumbnail image to view a larger map.

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

GIS-based quantitative tolerances maps

The Contiguous USA
 

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

State Maps

Alaska

Climate Factor	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Hawaii

Climate Factor	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Oregon

Climate Factor	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

(Subterranean Clover Adaptation & Use Map.)

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(SARE Managing Cover Crops Map. Source: Managing Cover Crops Profitably, 3rd Ed., Sustainable Agriculture Research & Education.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

Quantitative Tolerances GIS Maps

The contiguous USA

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Wet Image	pH Wet Image	Climate and Soil Wet Image
Minimum Temperature Dry Image	pH Dry Image	Climate and Soil Dry Image
Maximum Temperature Wet Image	Drainage Wet Image	All Soil Image
Precipitation Wet Image	Salinity Wet Image	All Climate Wet Image
Precipitation Dry Image	Salinity Dry Image	All Climate Dry Image

Map designations of wet and dry refer to different precipitation requirements for current use areas (40-60 inch rainfall zones, designated wet) and potential use areas (16-26 inch rainfall zones, designated dry). 

State Maps

Alaska

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Wet Image	pH Wet Image	Climate and Soil Wet Image
Minimum Temperature Dry Image	pH Dry Image	Climate and Soil Dry Image
Maximum Temperature Wet Image	Drainage Wet Image	All Soil Wet Image
Precipitation Wet Image	Salinity Wet Image	All Climate Wet Image
Precipitation Dry Image	Salinity Dry Image	All Climate Dry Image

Hawaii

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Wet Image	pH Wet Image	Climate and Soil Wet Image
Minimum Temperature Dry Image	pH Dry Image	Climate and Soil Dry Image
Maximum Temperature Wet Image	Drainage Wet Image	All Soil Wet Image
Precipitation Wet Image	Salinity Wet Image	All Climate Wet Image
Precipitation Dry Image	Salinity Dry Image	All Climate Dry Image

Oregon

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Wet Image	pH Wet Image	Climate and Soil Wet Image
Minimum Temperature Dry Image	pH Dry Image	Climate and Soil Dry Image
Maximum Temperature Wet Image	Drainage Wet Image	All Soil Wet Image
Precipitation Wet Image	Salinity Wet Image	All Climate Wet Image
Precipitation Dry Image	Salinity Dry Image	All Climate Dry Image

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

[[{"fid":"1246","view_mode":"default","fields":{"format":"default","alignment":"center","field_file_image_alt_text[und][0][value]":false,"field_file_image_title_text[und][0][value]":"White clover Adaptation and Use map - FORAGES","external_url":""},"type":"media","field_deltas":{"2":{"format":"default","alignment":"center","field_file_image_alt_text[und][0][value]":false,"field_file_image_title_text[und][0][value]":"White clover Adaptation and Use map - FORAGES","external_url":""}},"link_text":null,"attributes":{"title":"White clover Adaptation and Use map - FORAGES","class":"media-element file-default media-wysiwyg-align-center","data-delta":"2"}}]]

(White clover adaptation an use map.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database.

GIS-based Quantitative Tolerances Maps

The contiguous U.S.

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

State Maps

 Alaska

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

Hawaii

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image

 
Oregon

Climate Factors	Soil Factors	Combined Factors
Minimum Temperature Image	pH Image	Climate and Soil Image
Maximum Temperature Image	Drainage Image	All Soil Image
Precipitation Image	Salinity Image	All Climate Image