This is a dormitory for solitary bees. It is a bundle of woody sticks chosen for their varying "pith" diameter. The stems are about 12" (300mm) long. One quickly runs into diminishing returns as the bees will only tunnel a limited distance into the twigs. The length is determined more by the ease of handling from the human end than by what is optimal for the bees.
The sticks with the large, dark piths are Staghorn Sumac. The sidewalls of these twigs are so fragile that it is necessary to use a VERY sharp set of pruning shears. The stems with the lighter piths are Box Elder. Not pictured are stems of hybrid poplar. I doubt that the species selected are critical as long as the property owner offers a range of pith diameters for the bees to sort through. Cutting natural stems provides this variation as a free benefit.
|Some people create "Solitary Bee Hotels" by drilling holes into chunks of wood. The most popular Solitary Bees seem to favor holes with a diameter of about 5/16" (about 8mm). Picture from HERE|
Some species of bees (and there are hundreds, if not thousands) will not nest in a used stem. She will only lay eggs in those stems that she personally mines the pith out of.
It is doubtful that I really need to put these nests out. I have many, many broken, exposed stems on the property. That is what happens when your management plan favors bunny rabbits.
Still, it was easy. It took no more than a couple of minutes to cut the stems and make each bundle. And I had a bit of fun outside.
I intend to report if there is any evidence that Solitary Bees (and/or wasps) made use of these bundles for laying eggs.
---To Be Continued---