last updated 19 Mar 2021

Bee decline:

Commercial honeybees, which pollinate $15 billion worth of crops in the United States annually, have teetered on the brink of collapse for nearly a decade. A third of all bee colonies have died each year since 2006, on average, according to a 2015 report from the U.S. Department of Agriculture.

Scientists say the mysterious phenomenon, known as colony collapse disorder, may be the result of at least 60 environmental factors that combine to cripple honeybees — including pesticides, disease, malnutrition, loss of habitat and climate change.

Beekeepers, however, say the honeybee's single greatest threat is a virus-carrying parasite called the varroa mite.

Managed Pollinator Protection Plans (MP3s). EPA is promoting MP3s to address potential pesticide exposure to bees at and beyond the site of the application. Spraying with Acetamiprid, clothianidin, dinotefuran, imidacloprid, and thiamethoxam. These chemicals, collectively known as neonicotinoids, are a group of insecticides used on a wide variety of crops, turf, ornamentals, pets (for flea treatment), and other residential and commercial indoor and outdoor uses.

Varroa mites have devastated U.S. beehives since the late 1980s, when they arrived here from Asia. In 1996, half of the colonies east of the Mississippi River died due to mite infestations.

Policy Mitigating Acute Risk to Bees from Pesticide Products EPA

Nanotechnology-based pesticides (NBP):

Molecules | Free Full-Text | Potential Risk to Pollinators from Nanotechnology-Based Pesticides | MDPI

Scientists discover what's killing the bees and it's worse than you thought -- Quartz

Wild bees decline where crop pollination most needed, study finds | UC Davis 2016
UC Davis Part of Newly Established UC Network to Strengthen Bee Health, Crop Pollination - Entomology & Nematology News - ANR Blogs 2021

Lacy Phacelia:
Lacy Phacelia can be planted between rows in orchards to attract bees and as a cover crop.
What Is Lacy Phacelia: Learn About Growing Purple Tansy Wildflower
Making a Difference for California - Lacy Phacelia 1 considered one of the top 20 honey-producing flowers.
Overview of potential uses as a cover crop in orchards and vienyards
Blue Orchard Bee - Watch This Bee Build Her Bee-jeweled Nest

Ground Nesting Bees:
Due to their beneficial role as pollinators and their lack of aggressive behavior, please consider maintaining these important bee pollinators in your backyard!
530-500-2747 Nino Lab Website entomology

Katherine Jarvis-Shean
Sacramento-Solano-Yolo Orchard Systems Advisor
Univ. California Cooperative Extension
70 Cottonwood St, Woodland, CA
(530) 377-9528\
Recommended by Kelly Huff at Dixon Resource Conservation District (RCD)

Ground and Wood Nesting Bees: Learn to Identify Common Backyard Species | Gardener's Path
Fungi (mushrooms) boost bee imune system and may attack mites