I would like to hear from forum members who keep mason bee what they do to stop this little wasp from raiding of a good number of cocoons. Is there a nesting system that can prevent that? We all know that neither the cardboard tubes nor the staking blocks stop the plunder. Any body have experimented with the cardboard tubes and liner? Or this little guys are still able to drill throw. I will appreciate your impute.
I've been keeping Mason bees for a number of years and have noticed the parasitic wasps that chew small holes through the cardboard tubes. However, I haven't considered them to be a serious problem so far because they only affected a small percentage of the bee pupae. To me the pollen mites are a far more serious problem. Nevertheless, I do try to limit future damage by eliminating any parasitized cocoons from the hatching box. While extracting cocoons for cleaning, I always squeeze each one lightly to make sure there is a solid bee body inside. If the cocoon feels squishy, the pupa has either died or been replaced by a mass of tiny wasp larvae. By eliminating the squishy cocoons, the wasp population should be reduced, at least in principle. Since the wasp larvae always seem to be at an earlier stage of their life cycle than the bees, I assume that they hatch later. So it might be possible to eliminate them simply by destroying any cocoons that haven't hatched by the time that the bees normally do. But I'm not sure about this; I'll check into it this year. I'm also experimenting with something different for bee tubes: natural tubes made from sections of Japanese Knotweed. I'm sure you've seen it around; it's an invasive exotic that grows like crazy during the summer, only to have the above ground parts die with the first frost. The stems turn brown and persist through the winter, and a certain percentage are close to the right size for Mason bee tubes. So far I haven't found any occupied tubes that had wasp holes drilled through them, but I haven't been looking for them; and I haven't finished extracting all of this year's cocoons. If you're interested in this, I'll let you know if I find any tubes with wasp holes.
Pasquale, See if you can find a Copy of "The Orchard Mason Bee" by Brian L. Griffin. 1st book, green, published 1993 and second, orangish, thicker, more info, volume published 1999. The Author lives in Bellingham. I bought the first volume years ago and found the 2nd in a used book store. He didn't "just write" a book. He raises and sells Mason Bees and their paraphenalia and appears to be very knowledgeable. Barbara Lloyd Anacortes, WA
Pardon my ignorance but I always thought that mason bees were a nuisance as they tend to bore into the wood structures of homes and such. Other than polination, to they occupy any other roles in the garden that I haven't yet heard of?
Mason bees are never a nuisance. They do a great job of pollinating fruit trees in the rose family, such as cherries, plums, peaches, pears, and apples. They are not aggressive at all; I've never been stung by them, even though I've released as many as a thousand or more in the spring. And they do not bore holes into anything. They always use existing openings of a suitable size, such as old nail holes. They are a real asset to the garden and should be encouraged to multiply.
Barbara, I have read the first edition of “ The Orchard Mason Bee “ by Brian L. Griffin and that is the one that inspired me to start my first colony. Ten years later it has become my hobby. I haven’t read the second edition, but I have contacted the local library and it is available. Thanks Pasquale
Hi VitoG I will be very interested to know if any parasitic wasps got throw your Japanese Knotweed section. I too was using the cardboard tubes, but after I Shaw a good number of cocoons being spoiled by this tiny wasp I discontinue their use. Cardboard tubes are not a satisfactory material for Mason bee nest. At the moment I make my won blocks witch are inaccessible to the parasitic wasp. The pollen mites are still a problem, but removing and washing the cocoon every year can control them. Currently I am working on something new that will farther reduce their infestation.
Pasquale, I wasn't really watching for parasitic wasps until I saw the start of this thread, but I hadn't noticed any in the knotweed tubes that I had processed up to that point. I inspected the last batch of tubes (about 40) more carefully and didn't find any wasp larvae or holes drilled in the tubes. This may or may not be significant, since, as I mentioned earlier, parasitic wasps have not been a big problem for me. As a side note, this was the first year that I used more knotweed than cardboard tubes; and I found the knotweed to be very efficient. The stems are easy to split open and extract the bee cocoons. They also come with the back end already sealed, which may deter some pests and saves the bees the extra effort of sealing off the back end. Mason bees also seem to prefer the knotweed tubes to some other types. I plan to use knotweed extensively from now on.
I've used hollow bamboo with great success, just put a parcel of them in a tin can under an eave, but I do find parasitic wasps do attack them. I cut them so the back is naturally sealed by a joint chamber. And while the wasp can't chew on the bamboo stick, they at times just go for the front door and chip away at the mud seal for access to the bee larvae. Here's a shot of my bamboo and tin can bee houses: http://tallcloverfarm.com/?p=224
Hello Tallclover, The Parasitic wasps are much too small to chew throw the mud plug, I believe the woodpeckers are more like the culprit, you can solve the problem by tying a piece of chicken wire around the can, making sure that it is at least 3 inches away from the bamboo tubes.
thank you so much -- a great tip, as I couldn't figure out how such a small wasp could make such a big hole. most appreciated --tc
