Columbia Plateau is a region between the Cascade Range and Rocky Mountains, characterized by arid sagebrush steppe and grassland, with extensive areas of dryland farming and irrigated agriculture.
Zone
Interior
Common Name
Columbia Plateau
CEC Level III Code
10.1.2
CEC Level II Code
10.1 Cold Deserts
Overview
Region facts
| Category | Details |
|---|---|
| Aliases | Columbia Plateau, CEC 10.1.2 |
| Geographic Range | The Columbia Plateau Ecoregion is located between the Cascade Range to the west and the Rocky Mountains to the east, covering central and southeastern Washington, north-central Oregon, and a small part of northwestern Idaho. |
| Climate Snapshot | The Columbia Plateau ecoregion has dry, mid-latitude desert and steppe climates with hot, dry summers, cold winters, a mean annual temperature between approximately 7°C and 12°C, and mean annual precipitation of 334 mm, ranging from 150 to about 600 mm. |
| Terrain Profile | The Columbia Plateau consists of tablelands of moderate to high relief with irregular plains and open hills, ranging in elevation from about 60 masl to over 1,500 masl, and is characterized by plateau flood basalts, deep loess soils, and scablands cut by massive floods. |
| Vegetation Cover | The Columbia Plateau is characterized by arid sagebrush steppe and grassland vegetation, primarily consisting of bluebunch wheatgrass, needleandthread, Sandberg bluegrass, Idaho fescue, and various big sagebrush and bitterbrush species, with alien cheatgrass present in some areas. |
| Wildlife Habitat | The Columbia Plateau is home to wildlife such as mule deer, pronghorn antelope, coyote, ground squirrels, black-tailed jackrabbit, and various birds of prey like the golden eagle and red-tailed hawk, alongside the western diamondback rattlesnake. |
Eco snapshot
The Columbia Plateau is characterized by arid sagebrush steppe and grassland vegetation, primarily consisting of bluebunch wheatgrass, needleandthread, Sandberg bluegrass, Idaho fescue, and various big sagebrush and bitterbrush species, with alien cheatgrass present in some areas.
The Columbia Plateau is home to wildlife such as mule deer, pronghorn antelope, coyote, ground squirrels, black-tailed jackrabbit, and various birds of prey like the golden eagle and red-tailed hawk, alongside the western diamondback rattlesnake.
Seasonal timing
Yearly needs
What pollinators need throughout the year, and what to do about it.
| Season | What pollinators need most | What you can do |
|---|---|---|
| Late winter/early spring | Early nectar/pollen; safe shelter | Plant/maintain early bloomers; leave some leaf litter and stems until warmer weather is steady |
| Spring | Lots of flowers; nesting sites | Plant natives; add clumps of the same plant; keep some bare ground and avoid mulch everywhere |
| Summer | Drought-resilient nectar; water access | Prioritize heat-tough bloomers; provide a shallow water dish with stones; water new plants thoughtfully |
| Late summer/fall | “Finish-line” blooms; seed/overwinter prep | Plant late bloomers; avoid fall clean-up that removes stems/seedheads too early |
| Winter | Undisturbed shelter | Leave stems, seedheads, and some natural debris; plan next season’s bloom sequence |
Seed mix concept
Spring starter: early bloomers that take advantage of spring moisture (often the biggest natural bloom window).
Summer bridge: drought-tough flowers that keep nectar/pollen available through hotter, drier weeks.
Fall finisher: late-season bloomers (often shrubs and asters/goldenrods) that help pollinators stock up before winter.
What You Can Do
Turn this knowledge into action. Whether you plant a single pot or a whole garden, you are building a vital bridge for local biodiversity.
Join the movement to restore our shared habitats.
Native plants
Asters are late-season wildflowers that bring a burst of daisy-like blooms when many gardens are winding down, making them a reliable choice for pollinator-friendly planting.
Blazing stars (Liatris) are upright, purple-pink wildflowers that bloom in showy spikes and are well-loved by many pollinators. They’re a strong choice for sunny gardens, borders, and meadow-style plantings.
Gilias (genus Gilia) are airy, nectar-rich wildflowers that can add quick color to sunny spots and help support a variety of pollinators.
Goldenrods are tough, sunny wildflowers in the genus Solidago that light up late-season gardens with golden blooms and provide reliable nectar and pollen when many other flowers are fading.
Penstemons (beardtongues) are hardy, flower-filled wildflowers that bring bright color and steady nectar to gardens and containers, especially in sunny spots with well-drained soil.
Phacelias are easygoing wildflowers in the genus Phacelia, known for their nectar-rich blooms that can bring lots of pollinator activity to gardens, schoolyards, and even containers.
Rabbitbrush is a tough, sun-loving shrub known for its bright yellow late-season blooms that can help keep pollinators fed when many other flowers are fading.
Sagebrushes are tough, aromatic shrubs in the genus Artemisia that can anchor a dry, sunny habitat and offer shelter and seasonal nectar for a range of insects.
Wild buckwheats (genus Eriogonum) are tough, long-blooming western native wildflowers that can turn dry, sunny spots into reliable pollinator stops.
Yarrow is a tough, easygoing wildflower that brings long-lasting blooms and steady pollinator visits to gardens, schoolyards, and even containers.
Pollinators
Adults visit flowers for nectar and can move pollen between blooms; their presence is a sign of diverse, functioning habitats.
Many brushfoots move pollen between flowers as they feed, and their caterpillars are part of healthy food webs.
Bumble bees are important pollinators of many wildflowers and garden plants, helping ecosystems and food crops reproduce.
Adults visit flowers for nectar and pollen, and many species’ larvae help keep plant-eating pests in check.
They can move pollen between flowers while feeding on nectar, especially for blooms that open or scent up in the evening.
They move pollen between flowers while foraging, helping many wild plants and garden plants set seed and fruit.
They move pollen between flowers while foraging, helping many wild plants and garden crops set seed and fruit.
They move pollen between flowers while foraging, helping many wild plants and garden plants set seed and fruit.
They can move pollen while drinking nectar, and they also help control many plant-eating insects.
They’re part of healthy food webs and plant communities, and their caterpillars depend on a wide range of native trees and shrubs.
Skippers visit many flowers for nectar and can help move pollen between blooms while they feed.
Many small moths move pollen while feeding on nectar, supporting wild plants and garden blooms—especially in the evening and at night.
Many adults visit flowers and can move pollen between blooms, while also helping control some garden pests.
Adult swallowtails visit many flowers for nectar and can help move pollen between blooms as they feed.
They help move pollen between flowers in gardens, parks, and natural areas, supporting seed and fruit production.
They visit a wide range of flowers for nectar and can help move pollen between blooms as they feed.
