The European honey bee receives most of the credit for crop pollination, but the number of managed honey bee hives is half of what it was in the 1950s; and this number continues to decline. Native bees, however, also contribute significantly to crop pollination and, on farms with significant natural habitat located nearby, may even provide all of the required pollination for some crops.

To support the native bee community, it is essential to provide nesting sites, in addition to floral resources. Unfortunately, heavily managed farm landscapes often lack the untilled ground, tree snags, plants, and small cavities that native bees require for nest construction. Improving the nesting opportunities for these important pollinators will increase their populations which can lead to higher crop yields, reduced dependence on imported European honey bees, and improved on-farm biodiversity. Continue reading →

While making decisions about which plant species are appropriate for restoration projects, several physical characteristics of the project site should be considered. Each plant species has preferences for physical conditions; some plants are very widely adaptable to moisture regimes, soil conditions, and light levels, and others are fairly demanding in their habitat requirements. Charts detailing the habitat preferences of northwest native plants are available in the “Resources” section of our website. This article will focus on riparian projects, with examples of species common in western Washington, Oregon and British Columbia; similar steps, however, can be adapted to other habitat types. Continue reading →

For the past 15 years the protection and enhancement of wetlands has become a major mission for state and federal governments. With the passage of the Clean Water Act, the new regulations have affected how we practice agriculture and conduct commercial and residential developments. In addition, riparian habitats have been enhanced or given protection, in part because of the listing of some fish species under the Endangered Species Act. Continue reading →

What is a green roof?

Green roof systems are described as an extension of the existing roof which involves a high quality water proofing and root repellant system, a drainage system, filter cloth, a lightweight growing medium and plants.¹While there is some debate as to the effectiveness of green roof structures at addressing some of the larger issues associated with urban environmental degradations and climate change, green roofs have been found be beneficial. For example, these systems have been found to lower rooftop and building temperatures, thereby reducing the urban heat island effect found in so many of today’s cities, as well as improving the quality of stormwater runoff while decreasing the amount of runoff during storm events. Green roofs also slow precipitation that rooftops capture so that when it drains to the public sewer system, or some other receiving body, it happens over a period of hours and sometimes days rather than minutes or seconds.  This reduction in rainwater release dampens the pulse, or volume of water, that must be transported off-site and treated in wastewater plants. In cities or areas with combined rainwater and sewer systems, such as Seattle and Portland, this pulse sometimes overwhelms the wastewater treatment plant, resulting in released sewage and rainwater. In our region, preventing combined sewer overflows is an important action for improving the ecological health of Puget Sound and other large bodies of water. Continue reading →

INTRODUCTION

Native plant propagation, restoration, and conservation are complex activities that require many steps and decisions, and face many challenges. On one hand, there is broad agreement, at least among restorationists, over the importance of native plants and the benefits of habitat restoration. But on the other, there is widespread uncertainty and dissent about how to achieve these restoration goals. What should be planted and where? How should plant-materials for restoration be obtained? Where should they come from? What is the overall goal? The objective of this paper is to identify areas of agreement and disagreement to help frame debates in native plant restoration, and thus improve our ability to discuss and conduct this work from a position of mutual understanding and productive dialogue. Continue reading →