Our data

Native plant gardens support pollinators, conserve water, support local ecosystems, reduce pollution and harmful runoff. With increased habitat loss, we believe our built landscapes will play an increasingly important role in the survival of species and ultimately our food webs. Locally native gardens are the landscapes of the new millennium, and Calscape is the tool that makes them possible. How do we do it?

Right plant, right place

Methodology

For a given location to be included in a given plant's geographic range, a natural specimen of that plant needs to have been observed by a botanist within 10 miles of that location, and the location must be suitable within the local climate, elevation, and Jepson geographic parameters. Nursery cultivars do not have an estimated natural range, so they are not included in the plant observations data.

Plant observations

Drawing from nearly two million verified field sightings, Calscape's range maps present a comprehensive view of California's native plants. These findings span 150 years and are meticulously cataloged by the Consortium of California Herbaria.

About the Consortium of California Herbaria

Climate and elevation ranges

California’s native plants are adapted to a range of elevations, temperatures, and moisture levels. To show up in a location on Calscape, the plant must be within the elevation, annual precipitation, summer precipitation, coldest month average temperature, hottest month average temperature, and humidity ranges in which that plant grows. Climate data used in creation of plant and butterfly/moth range maps is from PRISM Climate Group, Oregon State University, using 30 year (1981-2010) annual normals at an 800 meter spatial resolution.

About the PRISM Climate Group

Ecoregions

An ecoregion is a geographic area characterized by similar soil types, slopes, climate, and plant assemblages. Calscape’s plant maps are generated using Jepson ecoregions to provide a scientifically-backed framework for understanding California's diverse plant habitats.

Explore Jepson ecoregions

Plant profile details

For successful native plant landscaping and nature restoration, it's important to grow plants that are native to your location in spots with the right soil, sun, and water conditions. Before finalizing which native plants to grow and where to plant them, review the Calscape plant descriptions to ensure they are placed in suitable conditions.

Plant detail sources

Plants for bats

Bat Conservation International developed a list of California native plants by identifying those that 1) support numerous moth species or moth species known to be bat food, and 2) are available at multiple nurseries. For certain plant groups, such as oaks, they included most species even if they’re only found at a few nurseries, due to their significant benefits for moths and bats. We plan to soon include cultivars as well.

Bat Conservation International

About

Plant profiles have been extensively edited and enhanced by Calscape volunteer editors. Wikipedia was an important original source for the "About" sections on the Calscape plant pages. Other general sources include Calflora, CNPS Manual of Vegetation Online, Jepson eFlora, Las Pilitas, Theodore Payne, Tree of Life, and The Xerces Society.

Become a Calscape contributor!

Seed propagation

The Santa Barbara Botanic Garden provided information on propagating from seed, as given in “Seed Propagation of Native California Plants” by Dara E. Emery. Over time, volunteers have continued to build on this information.

Explore seed propagation

Cultivars

Maintaining an up-to-date catalog of cultivars is a continuous effort. We extend special thanks to nursery partners for their assistance in developing a comprehensive database of cultivars. Our nurseries and volunteers consistently provide updates, and we welcome new contributions!

Add a cultivar to Calscape!

Plant communities

We base our designation of generalized plant communities on “California Native Plants for the Garden” by Carol Bornstein, David Fross, and Bart O’Brien. Although scientific studies have identified anywhere from two dozen to hundreds of plant communities, we have adopted a simplified structure to keep information accessible.

Water use data

Water Use Classification of Landscape Species (WUCOLS) provides crucial water use classifications for California landscapes, which Calscape uses to help users estimate tailored irrigation needs across specific climate regions, promoting efficient water management. WUCOLS has been significantly updated with CS2, so water needs may have changed compared to what you used to see in Calscape. Over time, volunteers have contributed additional watering care instructions for native plants.

WUCOLS database

Calphotos

Special thanks for Calphotos for their invaluable help in acquiring these images. Authorship and copyright information is shown under each plant photo. CalPhotos is a collection of 764,465 photos of plants, animals, fossils, people, and landscapes from around the world. A variety of organizations and individuals have contributed photographs to CalPhotos.

Calphotos

Wikimedia photos

Wikipedia is also a source for plant photos available through Wikimedia Commons. All photographs on Calscape that were originally from Wikimedia Commons are available for reuse under conditions set by the authors and described in each photo.

Wikimedia

Butterflies and moths in Calscape

Why it matters

Few non-native plants can serve as host plants for native butterfly or moth species. Though butterflies and moths often prefer native nectar sources, they can usually make do with non-native nectar. Their caterpillar offspring, however, need particular native plant species in order to survive. They eat leaves of the plant on which their parents laid eggs. Among those caterpillars, 90 percent of species can't overcome the chemical and structural defenses of most plants. They can survive only if the eggs from which they hatch were laid on one of the few native plant species with which their own species co-evolved. This is the primary reason why native landscapes support 35 times more caterpillar biomass than non-native landscapes.

Host plants

The caterpillars of most butterfly and moth species have evolved to eat the leaves of just a small number of plant species native to their geographic range, sometimes in just one genus of plants. These plants are called "host plants" for that species of butterfly or moth. If a given species of butterfly or moth cant find their particular host plants in an area, it will die out in that area. In Calscape, "Confirmed" host plants have all been verified as host plant species for the butterflies and moths native to this location. For nursery cultivars and hybrids, there is no data available to confirm their suitability as host plants. Likely host plants all belong to a known host genus for this species, but the individual plants have not been verified as host plants.

Methodology

Calscape's butterfly and plant data, derived from 200,000 geo-referenced field observations sourced from multiple channels, estimates the geographic range of each species within distinct climate conditions. Overlaps between plant and butterfly and moth ranges indicate probable interaction, with confirmed interactions validated through observations.

Observation data

Our estimates for the natural geographic range of butterfly and moth species in California are based on approximately 200,000 geo-referenced field observations provided through GBIF iDigBio, the Symbiota Collections of Arthropods Network and Butterflies and Moths of North America, aggregating digitized collections of 40 universities, entomological museums and other institutions, and research grade observations from iNaturalist.

Geographic range and climate parameters

For a given square mile to be included in the estimated geographic range of a particular butterfly or moth species, that species must have been observed within 50 miles of that square mile, and that square mile must fall within annual precipitation, summer precipitation, coldest month average temperature, hottest month average temperature, and humidity ranges in which that species has been observed in the state.

Likely host plants

Likely host plants all belong to a known host genus for the butterflies and moths native to this location, but the individual plant species have not been verified as host plants. Plants shown as hosts for a particular butterfly or moth species must meet two requirements: 1. the genus of that plant species must be a known host for that species of butterfly or moth, AND 2. the natural geographic range of that plant species must overlap with the natural geographic range of that butterfly or moth species.

Sourced from National Wildlife Federation, National History Museum, and other databases

Photos

Sources of plant and butterfly and moth photos include Calphotos, GBIF (GBIF.org (27 August 2019), iDigBio, the Symbiota Collections of Arthropods Network and dozens of amazing plant photographers who have agreed to share their photos with Calscape.

Collaborate with Calscape today!

We are deeply grateful for the wealth of knowledge, data, and support provided by a diverse group of institutions, organizations, and individuals. Their contributions have been invaluable in our efforts to promote the growth and understanding of native California plants and their ecosystems.

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