Protecting pollinators

Pollinators, like bees and butterflies, rely on different sources of pollen and need different types of habitat. Having a diversity of pollen sources and of habitat, within and adjacent to our right of way, is critical to pollinator health. 

We are creating and studying pollinator habitat in different areas around the state, most recently, at the Scatter Creek Rest Area.

Scatter Creek research project

In 2024, WSDOT created a one-acre public demonstration “lab” (PDF 812KB) of pollinator habitat at the Scatter Creek Rest Area. 

This lab tests new products and theories for pollinator establishment and success. The project used common construction methods so we could easily repeat it throughout the state in different projects. 

Research plots

To create our demonstration lab, we divided the one-acre space into eight individual plots. They are separated by split-rail wood fencing for ease of long-term maintenance delineation and monitoring while limiting public access. Each plot represents a unique strategy for pollinator habitat creation using different soil and seeding treatments.

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Soil treatments

We are testing three different soil treatments at Scatter Creek to compare results:

• Compost -  Commonly used on our projects to compare a typical approach with other alternatives. A 3-inch depth was applied.
• Biochar Amended Compost (BAC) -  An 85% Compost, 15% Biochar blend.  We want to better understand the soil quality capabilities for Biochar, a relatively unused product, for plant establishment success. A 3-inch depth was applied.
• Biotic Soil Amendment (BSA) - A  soil enhancing organic material that includes microbial stimulators, growth mediums, and soil stabilizers to accelerate the soil building capabilities of existing native soils. BSA was hydraulically applied with the hydroseeding process.

All plots used the same combination of grass and pollinator species and rates for seeding to not influence plant diversity responses to the soil treatments.

Monitoring

We will monitor the plots for the next several years to assess:

• Establishment success
• Changes to flowering cycles
• Species diversity
• Natural plant recruitment
• Soil chemistry
• Pollinator insect presence 

Automated data is collected by the Phenode system monitoring equipment located on site. Phenode collects data in real time measuring weather patterns including temperature, humidity, rainfall, wind, and soil characteristics (moisture, temperature, and salinity). 

We will also provide education to the public and rest area visitors through interpretative signage and updating this webpage with new discoveries as part of our on-going commitment to researching measurable outcomes.
 

WSDOT is also providing enhanced carbon sequestration opportunities through native Oregon White Oak tree installation including climate resiliency with assisted species migration. Find out more about the related work happening around (PDF 2.1MB) the Scatter Creek rest area and surrounding natural prairie. 

Creating beautiful and beneficial roadside landscapes

Pollinator meadows (PDF 2.2KB) are planted with native, non-invasive flowering plants and grasses that attract vital pollinators, such as bees, butterflies, and birds. Meadows like these are crucial for our ecosystems as they support the pollinators responsible for approximately one-third of the food we eat.

Pollinators are essential to Washington’s agriculture and ecosystem health. The WSDOT Pollinator Friendly Practices Plan (PDF 1.26MB) details the agency’s resilience goals and ongoing efforts to protect pollinator populations.

Prairie ecosystems along the roadside

Open prairie ecosystems (PDF 783KB) have been a defining feature of Western Washington and the Puget Sound Basin since the end of the last Ice Age. The sections of open prairie landscape were formed in part by the forces of ancient glaciers and the activities of the indigenous people in the area. 

Pollinators

Animal pollinators play a crucial role in flowering plant reproduction and in the production of most fruits and vegetables. Neither plant nor pollinator populations can exist in isolation – should one disappear, the other is one generation away from disaster.

Follow the links below to learn about these very important pollinators and the flowers they visit (Source: USDA Forest Service):

• Ants
• Bats
• Bees
• Beetles
• Birds
• Butterflies
• Flies
• Moths
• Unusual
• Wasps

Review our Creation of pollinator habitat list (PDF 233KB) to learn how most restoration sites can provide habitat for a wide variety of pollinators.

You can also refer to our flowering charts to help choose native plants for your region:

• Sequential Flowering Native Plants of the PNW Western WA (PDF 62KB)
• Sequential Flowering Native Plants of the PNW Eastern WA (PDF 54KB)
• Sequential Flowering Native Prairie Species South Puget Sound (PDF 54KB)

What is pollination?

Pollination: the act of transferring pollen grains from the male anther of a flower to the female stigma.

Flowers rely on vectors to move pollen, including wind, water, birds, insects, butterflies, bats, and other animals that visit flowers. We call animals or insects that transfer pollen from plant to plant “pollinators”.

Pollination usually occurs during an animal’s activity on a flower. While the pollinator eats, collects pollen for its protein and other nutrition, or sips nectar from the flower, pollen grains attach themselves to the animal’s body. When the animal visits another flower for the same reason, pollen can fall off onto the flower’s stigma and may result in successful reproduction of the flower. (Source: USDA Forest Service)