Cut lengths of reeds are an alternative to drilled wooden blocks for trap-nesting and managing some bees, such as the blue orchard bee.  The common reed, Phragmites australis, is a marsh-loving invasive Eurasian species that is found worldwide.  Its stems are perfect for the task.

Cut dead reed stems using hand clippers.  Cut a month  or more after frosts, or use last year's stems, as cut growing reeds will crack while dying.  Take only the largest reeds, removing attached leaves.

Reeds have hollow stems, divided periodically by nodes, just like bamboo. 

For bee nesting, saw stems into pieces, each having one node.  The node provides the nesting bee with a back plug.  Bees rarely use unplugged tubes.

The soft reeds are easily cut to length, either using a fine-toothed coping saw or an electric band saw.  Bundling reeds to present uneven lengths can help a nesting female find her nest.  Discard thin-walled pieces, as they are accessible to bee parasites, and lengths shorter than 4 inches, which yield mostly male offspring.  For blue orchard bees, a cavity no smaller than a pencil's diameter is desired.

Reeds are easily split to reveal their nest contents.  The split halves can be taped back together.