I use a wedge of corrugated plastic to secure nesting trays into a Highrise home. Corrugated plastic sheeting is made from 100% recyclable plastic and it is easy to cut and fold to fit any cavity. I jam it into the space above the nesting trays and trays are secured into the Highrise.
For the second year in a row, I have had mason bees nesting in these tiny nesting cavities. These tiny cocoons are similar in colour as Osmia lignaria cocoons, but much smaller in size. I have not seen this small bee fly, so I do not know what they look like nor do I know what time of the year they appear. If you have a piece of corrugated plastic, set a piece in amongst your other nest materials and see what happens.
| The spring mason bee cocoon is on the left (with its nesting trays on the far left). The tiny summer mason bee cocoon is on the right. |
| After slicing the nesting tunnel open you can see how the tiny cocoon fits into the tiny nesting tunnel. |
| Closeup of plastic corrugated sheets filled with mud plugs. |



