Though the Redeemer Valley Farm’s community garden has honeybee hives all around, there are native bees that may be even more important and efficient for pollination – and you can support them in your home or garden plot!
In spring, as the temperatures begin to rise and fruit trees start to bloom, the blue orchard mason bee (osmia lignaria) emerges in eastern Pennsylvania. These native bees are about the same size as a honeybee but can be identified by their dark metallic blue color, which may sometimes appear black. Their bodies are covered in hair, which collects pollen while they forage, and are one of the few native pollinators that are managed in agriculture. They are solitary bees, each tending to their own brood (instead of living in a large colony like honeybees), but they often nest near one another.
During the summer, leafcutter bees (Megachile spp.) become active, but also just for a few weeks. These solitary bees are recognized by their black bodies with white, silver, or orange hairs. Females typically nest in rotting wood and get their name from lining their nests with small pieces of leaves. Unlike most bees that carry pollen on their hind legs, leafcutter bees transport pollen on the underside of their abdomens, a unique trait that distinguishes them from other bee species.
It is easy to create a native bee house to support these local bees (neither of which is aggressive – you’d have to work really hard to get stung). Perhaps the best way is to use phragmites, an invasive reed with hollow stems, to mimic the bees’ natural nesting sites. Phragmites grow in moist areas in our region and are easily recognizable because they can reach 10 feet or taller and sport plumes of seeds at the top. Harvest the phragmites reeds and cut them into lengths of about 6-8 inches, ensuring one end is naturally closed by the node of the reed. Bundle these tubes together and place them in a sheltered location that receives morning sun. It is best to replace the phragmites tubes each year. If making a bee house is not for you, there are many on-line and in-store sources where bee houses can be purchased. Just search for ‘bee houses for native bees.’
You will know that your native bee habitat has been successful if the bees lay eggs in the nesting tubes. Blue orchard mason bees seal their tubes with mud plugs in May. Leaf cutter bees seal their nesting tubes with chewed leaves later in the summer. The eggs will remain dormant over winter, then hatch and repeat the pollination and nesting cycle the following year.
Submitted by Aaron Rubin
References: https://www.fs.usda.gov/wildflowers/pollinators/pollinator-of-the-month/mason_bees.shtml
https://extension.psu.edu/conserving-wild-bees-in-pennsylvania