Day: April 5, 2021

Put Out Your Mason Bees when Pollinators are Needed

NOTE: I have updated this 2016 post in order to make it appear closer to the other mason bee information

The time to put out your mason bees which have been overwintered in your refrigerator is when you need them to do their work. I release mine in batches.  The first batch was several weeks ago when the peaches and nectarines were in bloom. This week, the pears, plums and cherries are in bloom so I just put out  another batch of cocoons near my bee homes. I will save the last batch for my apple trees which bloom later.

2016-03-31 peachI had to transplant this peach tree this year to the corner of the vegetable preparation building so I found another good spot to place a bee home.

Mason bees always need good mud

NOTE: I have updated this 2016 post in order to make it appear closer to the other mason bee information. 

Don’t forget to make sure that your mason bees can find a good source of mud while they are laying their eggs in your tubes.  I discovered a year ago that if you provide a reliable source within a few metres of the bee houses, they will use less energy to gather mud and will therefore be more efficient.

mason bee crawls into the side tunnel
mason bee crawls into the side tunnel

See this post I did. Another observation has led me to believe that they prefer to collect mud in horizontal holes in the side of a trench.  This trench is kept wet throughout the nest-building period, and I dig holes into the walls of the trench.  It is probably an adaptation to prevent predation, as they would be easy targets on an open patch of wet soil.  They also prefer “clayish ” mud, as any good mason knows that their mud needs to be sticky… Sandy doesn’t do it!

This year I gathered some freshly exposed clay and added it to my mud trench.

Holes drilled in clay for a mud source for mason bees
Holes drilled in clay for a mud source for mason bees

 

Monodontomerus wasps: Parasites of Mason Bees

ARCHIVAL: This post has been re-dated from 2015 in order to position it closer in the blog to Mason Bee Information
I find that if I remove a set of Mason Bees from the refrigerator and put them out by the colonies to emerge from their cocoons as the weather warms up, if they are not hatched within a week, and yet look like viable cocoons, you can suspect that they may have Monodontomerus wasp parasites,

I opened several cocoons today and the results are shown below.  In many of the cocoons the bee was still alive, but must be weakened so that they can’t chew their way out. If I got them soon enough before they were being thoroughly eaten, often with small white eggs attached to the outside which the bee brushes off easily, they can fly away after a few minutes.  In the handful of about 100 cocoons that I looked through today, less than 5 % seem to be affected like this.

This external website has  a good video on how Monodontomerus wasps attack mason bees.

This external website provides a method of “candling” to check for Monodontomerus parasitic wasp larvae.

Other links on the websites to parasites