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The Rusty Patched Bumble Bee is Protected!

The Rusty Patched Bumble Bee is the first bee in the continental United States to become an endangered species.
Announced on the first day of spring, March 21, 2017, the Rusty Patched Bumble Bee is now protected under the Endangered Species Act. In their press release, The Xereces Society wrote: “T his historic moment comes as a result of a listing petition filed by the Xerces Society for Invertebrate Conservation. Steps can now be taken to work toward the recovery of this species, which previously was common from Minnesota to the Atlantic.” (Read more)

Summer 2016

Sunday July 3rd, 2016

The Green Metallic Sweat Bee

Family: Halictidae

Genus: Agapostemon

Check out this site to identify your Agapostemon!

Sweat bees are very important pollinators as their large populations are second only to those of Apis, and for a small bee, they sure have large pollen sacs! Check out the picture above, taken by Lisa Mason. That tiny bee is moving a lot of pollen around. Because  Agapostemon are generalists, they can reach a large variety of flowers that may not be pollinated otherwise.

They live in solitary, underground dens or in large communes of 200+ females. The females of Agapostemon can have solid green-blue metallic color over their entire body, or be similar to males with a striped abdomen and  are quite fast fliers, while the males typically have a striped abdomen and fly a little more slowly to search for females.

Some great ways to cultivate space for these bees in your garden include:

  1. Leave bare ground for them to nest. Plastic mulch, weed barrier, rocks, and even wood chips can interrupt sweat bee nesting and reduce their populations.
  2. Plant a large number and variety of pollinator friendly. Sweat bees are generalists and will pollinate many different plants.


Little Trudy Catmint from Plant Select

(Picture from Plant Select Website)

Little Trudy is a compact Catmint with silvery leaves and purple flowers that is perfect for xeric conditions (seasonal dry weather patterns) and attracting pollinators. With a lot of flowers on each stem, green metallic sweat bees will find this plant to be a great resource for pollen and nectar! I’ve seen sweat bees, bumblebees, and honey bees at Little Trudy Catmint plants this summer. Where have you seen green metallic sweat bees?

Monday June 20th, 2016


A cuckoo bee is a cleptoparasitic bee that may come from about 16 social bee lineages including Bombus and Apidae, as well as 31 solitary bees, mostly in Apidae, Megachilidae, and Halictidae. Collectively, cuckoo bees make up a large portion of the bee population.

Cleptoparasitism describes the cuckoo bird-like behavior of laying their brood in the nests of other bees. They tend to look similar to the bees they parasitize and when their young are hatched, they will be tended by the host bees. Sometimes the queen of the host species will be killed and replaced by a cuckoo bee queen.

Cuckoo bees can be distinguished from other bees by their thickened exoskeletons and reduced hair quantities. They are not typically pollinators and lack pollen sacs and other features that would typically help with the job. Have you seen cuckoo bees this summer? (Photo: Diana Wilson)

evening primrose

Denver Gold Columbine from Plant Select

The bright yellow flowers on the Denver Gold Columbine® (Aquilegia chrysantha) can be over 3-inches long. They can bloom from May to autumn. This perennial can tolerate dry, shady growing conditions, but thrives in the sun. They generally grow between 28-32 inches in height, and can be 16-18 inches wide. To encourage longer blooming throughout the season, you can remove the flowers that are done blooming.  The Denver Gold® variety is actually longer lived than most other columbines. The plant is well-adapted to grow at higher elevations. You can find this variety at the CSU Trial Gardens. We have observed striped sweat bees on the flowers this summer. Have you seen any other bees on the Denver Gold®? (Photo: Lisa Mason)

Thursday June 2nd, 2016


Pictured above is the famous Leafcutter bee, known in Latin as Megachile spp. This bee is often overlooked because of its solitary nature but it is an important native pollinator in Colorado. You can check out the Colorado State Extension Factsheet here to learn more about this neat bee!


This is the Silver Blade Evening Primrose by Plant Select. It is a hardy plant with a long flowering season that is perfectly suited to Northern Colorado and our native pollinators. Learn more about this flower and how to obtain it for your garden here.

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