Many native bees, such as the tiny, dark, small carpenter bee (genus Ceratina), utilize old, pithy stems as nesting habitat and overwintering sites. During the spring and summer, when these bees are actively seeking nesting sites, gathering pollen and laying eggs for the next generation, they search for dead twigs and stems with pithy centers that they can carve out for their nests.
How can you help provide natural habitat for these native bees? In the fall and winter, when pruning back shrubs that have pithy stems like raspberries, elderberries and hydrangea, or even flowers with thick-stemmed structures like coneflowers, sunflowers, and asters, leave an extra 8 to 10 inches of stem to harden and provide options for native bees looking for places to carve out their nesting sites the next season.
The accompanying photo shows raspberry canes that hardened over the winter and spring and were carved into by carpenter bees during the summer. Next spring, out will come the next generation of native pollinators!