Category: Mason Bees and Phragmites reed-grass tubes

Mason Bees.. The best pollinator for spring and early summer pollination of your fruit trees.

Release of the Last Mason Bees and isolation of Parasitic Mono wasps June 2015

The natural time for mason bee adults to emerge from the cocoons is normally hatchedmasonquite early, in February or March in the lower part of Vancouver Island. This year I decided to hold some dormant in the refrigerator for a longer time to see if they would still hatch out successfully. By early June some of the bees were actually emerging and remaining very still in their jars in the refrigerator.

As soon as jar was removed from the fridge, once they heated up they would fly off.  (Note: as of June 25 they are still very active around the nest boxes.)

After a week of leaving the cocoons, I isolated the unhatched ones in a sealed jar, and sure enough in a few days the parasitic wasps were on the inside of the container.

Each time i had made a release of cocoons throughout the spring, I waited for at least a week and if they didn’t hatch, I opened them with a razor blaid and released any live bees. about one in 30 unhatched cocoons would have parasitic larvae, so maybe they are programmed to emerge more than a week after the regular bees emerge, in that way, they would have active cocoon building so they could immediately begin laying eggs in the cocoons. ??

 

NOTE: I have updated this 2015 post in order to make it appear closer to the other mason bee information

Identification of Wasp Larvae from Mason Bee tubes

ARCHIVAL: This post has been re-dated from 2016 in order to position it closer in the blog to Mason Bee Information

Wings held partly erect.
Wings held partly erect.

In the previous post I indicated I was trying to identify wasps that had taken up residence in mason bee tubes, without actually parasitizing the mason bees

 

 

largewasplarvaeI found the larvae in tubes while removing the mason bee cocoons in the winter, and transferred them to a separate jar where I  let them hatch. By May 1 they were hatching so after taking a few pictures, I sent the images off to BugGuide.

The result after several months was an identification by an expert in entomology : Our thanks to  Matthias Buck of  The Invertebrate Zoology Section, Royal Alberta Museum, Edmonton, Alberta, Canada
http://bugguide.net/node/view/1218699#2158789

So he thinks there are actually three species represented in these pictures.

Food
Eumenines prey mainly upon moth larvae, although some take larvae of leaf-feeding beetles.
Adults take nectar.
Classification

Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata – Ants, Bees and Stinging Wasps)
Superfamily Vespoidea (Yellowjackets and Hornets, Paper Wasps; Potter, Mason and Pollen Wasps and allies)
Family Vespidae (Yellowjackets and Hornets, Paper Wasps; Potter, Mason and Pollen Wasps)
Subfamily Eumeninae (Potter and Mason Wasps)
Genus Ancistrocerus

There were three species identified from my photographs( labelled above) although it is very difficult to confirm identity without being able to examine a specimen. Next year I will be sure to send him samples to confirm, and I will certainly not destroy these larvae when cleaning out mason bee tubes.

Mason bee larvae and predation

I know I should have put the chicken wire fencing up sooner, as a bird, probably a woodpecker or a rat  pulled out the top 4 cm of tubes from two of my boxes, Fortunately it never opened all the tubes but a few were broken so I was able to open them and see the larvae stage inside

 

you can see the larvae attached to the plug of pollen in each section of the phragmites tube. At this stage one should not move or jar the tubes as the larvae can fall off the plug of food.  I was able to tape back up the tubes and the larvae inside should survive OK as long as they can reattach to the food pellet.

The solution, 1 inch opening chicken wire:

Mason bees pollinating kiwi fruit and the monodontomerus, parasitic wasp

This week I took out a few more mason bee which had already emerged from their cocoons  while still in the containers in the refrigerator. They sit very dormant when cold but take only minutes to get active as they warm up. Their normal time of emergence from dormancy would be much earlier in the year but releasing them now ensures pollination of the late blooming fruits.

It was time to add a few more bees to the population outside since  the strawberries continue to bloom and the kiwi fruit have started to bloom with this very warm weather we are having.

2015-06-04 strawber2a
Strawberry flowers

I also went around to all my mason bee boxes and removed the few cocoons that had not already hatched.

They either contained a dead bee or the larvae of the Monodontomerus, or “mono” which is a parasitic wasp that lays its eggs on the larva, usually within the cocoon of the mason bee. The tiny adult wasps emerged from one such cocoon. You can see the long penetrating ovipositer on the tail end. These have to be destroyed before they get to the bee larvae in the new cocoons.

 

NOTE: I have updated this 2015 post in order to make it appear closer to the other mason bee information

Plants for Pollinators in late May 2016

ARCHIVAL: This post has been re-dated from 2016 in order to position it closer in the blog to Mason Bee Information
The mason bees have almost stopped their work of pollination by now.  However several bumblebee species and honey bees were very active around certain plants in the yard this week.

Making the best of a bad situation

So you have gone out and bought or have been given a Costco bee house, shaped like a pretty alpine bungalow . Only problem is, their design is contrary to all the best practises of mason bee housing.

See the previous post I did on this here:

However, all is not lost. You can rehabilitate the house so that it has a better chance of working .

Steps to follow:

1. Remove all the short bamboo tubes which are glued in .. Just get a screwdriver and pliars and pry them out.

Nodes in bamboo tubes which meake the tube useless for bees.

2. Reject the ones with nodes halfway down the tube which allows only a few inches to be useful to the bees.  However if you have a drill, you could drill out these tubes.

3. The following diagrams show how you can split the tubes with an exacto blade and then tape them back up. This will allow you to remove the cocoons for cleaning at the end of the season and prevent a deadly buildup of parasitic mites.

4. In the tubes which have too large an opening, insert tubes of either phragmites reed, cardboard or rolled paper tubes so that these can be extracted at the end of the season to recover the cocoons.

5. Open-ended tubes should have the back end sealed.. I used a glue-gun to do this.

 

 

Mason Bees Houses

I have received several inquiries about making homes for Mason Bees. Here are some useful references that may give you ideas. They are expensive to buy and really not that hard to make , just make sure you use the type that can be cleaned out at the end of the season, removing the cocoons cleaning out the parasites and storing them for the winter. Do not use holes drilled in a wood block unless the holes are large enough to have a tube fit inside of them, so that the complete tube is removable.  The tube diameter that is best is  5/16” (8 mm) , but a variety of sizes close to this wont hurt.

They need a house, so go online and you will see a variety of ways to make one, buy one etc.  They are easy to make if you have access to a table saw or router. Place the bee home when completed  against a warm south facing wall.. be sure not to move it once they start using it as they cannot find entrances that easily if moved.
On the link on this  website https://www.gfletcher.ca/?cat=2  I give some other information on the Mason Bees.
You can also  buy various types of homes at local garden supply centres or order them on line..
The tube diameter that is best is  5/16” (8 mm)
Here’s one site , I believe he is up island.
and this one in Washington tells how to make your own: http://olypollinators.blogspot.ca/p/housing-mason-bees.html
stacking the Phragmites tubes in the bee house
stacking the Phragmites tubes in the bee house

Next winter I will harvest more of the Phragmites tubes so that I will have extras to sell. Then you just need the equivalent of a birdhouse without the  front on it.

NOTE: I have updated this 2015 post in order to make it appear closer to the other mason bee information.

Mason Bees Depositing eggs

NOTE: I have updated this 2015 post in order to make it appear closer to the other mason bee information

By early May many of the tubes are full and capped with mud. Here a female mason bee searches for the last hole she has been filling to deposit eggs or mud
By early May many of the tubes are full and capped with mud. Here a female mason bee searches for the last hole she has been filling to deposit eggs or mud
backed in
Backing in a tube to deposit the egg.
found-hole
Going in head first, probably meaning she is carrying mud to seal a compartment.
filled tubes
Almost all the tubes are filled and capped in this section

female.

NOTE: In 2024  I have re-dated this post in order to place it closer to the other mason bee posts ..

Destroy Empty Mason Bee Cocoons several weeks later..

A few weeks after your mason bee cocoons have hatched, remove the empty cocoons and any that have not opened and destroy them. In some of the unopened ones you might find the tiny larva of the parasitic mono wasp, referenced here on an earlier post.

https://youtu.be/yyf1ao1XjMc

Mason Bees need mud!

NOTE: I have updated this 2015 post in order to make it appear closer to the other mason bee information

When Mason bees are laying eggs in their tubes it is essential that they have an easily available source of wet soil for building the individual chambers in which the pollen and nectar are deposited and the eggs will be deposited . Separating each egg chamber is a mud wall and capping the tube at the entrance will be a mud plug.  I have dug a trench a few metres from the nest boxes a metre long  and about 20 cm deep in which I periodically soak with water.  Along the walls of the trench I have poked small tunnels since I have observed that the mason bees prefer to go into horizontal holes to pick up  the mud.