Problem: mason bees going into old tubes

" Hi & thank you for your response to my prior eMail of several weeks back.   Now I have another question.   First I have some good news.   It seems most of my  bees had not hatched from their tubes before the cold & stormy weather hit us.   Today there are lots of bees near the tubes & in my garden too!   There is a lot more debris below the tubes which means many bees from deeper in the tubes    have made their way out - mostly females to boot!

Now the question:  The bees are going back inside the "used tubes".   Will they re-use the old cardboard tubes or is there another reason they continue to enter last year's tubes?   Should I remove the tubes?    I have 2 of your houses with the colored Eco-Quicklock blocks.   I've added paper liners to about 20% of the holes & will see if the bees have a preference for the lined holes.   Bees are beginning to use the houses but it's too early to tell if there is a preference. 

 Thanks for your attention."

Hi Tony,

You have come up against one of the most difficult things to do in mason bee keeping i.e. get the bees to use new nesting-tunnels while the old ones are still present.  For the most part, it is not possible to exclude their use of old nesting tunnels.  Because mason bees re-use nesting tubes, that may be deceased, it is better to remove cocoons from nesting tubes in the fall- then the bees do not have a choice.  As soon as bees re-enter the old tubes, they are laying eggs.  In other words, if you remove them now, you would be destroying the new bees.  I would keep everything like you have it and in the fall- open all tubes, and harvest the cocoons.  Good luck.  Margriet

"Hi,   Thank you for your response.   This coming fall I'll do as you suggest & harvest the cocoons.  Tony L."