Current thinking, and the forum's wasp expert, suggests that traps should be placed away from hives otherwise there's a risk of attracting wasps to where you don't want them to be. (I hope I'm not misquoting Karol or trampling on his area of expertise)
That's very kind of you BeeJoyful but I'm not sure I deserve such an accolade when most of the jury is not just out but gone on an indefinite adjournment!
Protecting hives from wasps is not an easy thing to do and requires a detailed understanding of wasp behaviour, trap design and what I call IWM (integrated wasp management) strategies.
I know that a lot of bee keepers are having difficulties at the moment so I will try to help as best I can.
The first thing to understand is that wasp traps fall into one of two camps. They are either low efficiency (i.e. allow wasps to enter, feed and then escape) or high efficiency (i.e. kill 100% of the wasps that they catch).
These are three examples of low efficiency traps:
[ame="http://www.youtube.com/watch?v=2xllp6LCgFQ"]Wasp bottle trap showing escaping wasps - YouTube[/ame]
[ame="http://www.youtube.com/watch?v=Cs0KRE041lk"]Wasp (Tub) Trap Clip.mp4 - YouTube[/ame]
[ame="http://www.youtube.com/watch?v=3_L1pXXHzbI"]Wasp Pot.mp4 - YouTube[/ame]
I'm afraid forum rules mean I can't show you video clips of a high efficiency trap.
Low efficiency traps don't help no matter whether you place them near or away from hives. I've been running a poll on forum which shows that there appears to be no benefit in using low efficiency traps, i.e. the distribution of traps is the same relative proportion in the group that lost a hive (or hives) to the group which didn't. This is consistent with our own research not just with hives but other applications as well.
High efficiency traps are used in one of two ways depending on the nature of the problem, i.e. whether you have to deal with scouting wasps or swarm feeding wasps and it can be difficult to tell the difference at times.
Scouting wasps are essentially individual wasps that are looking for a food source which they have yet to report back to the nest. Swarm feeding wasps are wasps which have been recruited by a scout to a particular food source. Once wasps start swarm feeding on that food source then they will keep coming back to that food source until it is exhausted. We call this programmed feeding.
So, with scouting wasps the strategy is to intercept scouts arriving at the hive to prevent them returning to their nest to recruit more wasps. This means placing the trap either on top of the hive or immediately in front of the entrance to the hive before swarm feeding becomes established.
If swarm feeding has become established then other strategies have to be adopted. Essentially, the progammed feeding has to be interrupted, i.e. the food source on which the wasps are feeding must be removed or made unavailable and simultaneously, the wasps have to be caught and killed. If feeding is interrupted without mopping up the wasps then they will simply start looking for an alternative food source and will either find the hive again if relocated or find an alternative hive.
Best way to interrupt programmed feeding is to either seal the hive for a short period and place a high efficiency wasp trap directly in front of the sealed entrance or to move the hive a couple of feet and
simultaneously place the high efficiency wasp trap exactly in the same place as the original position of the entry to the hive. After a couple of hours the high efficiency wasp trap should have mopped up the swarm feeding wasps and should then be moved to the interception location to protect the hive from further scouting wasps.
Reducing the entrance to a hive and using a glass pane are a part of IWM. The pane of glass should be placed in front of the hive so that it makes contact along the length of the landing platform and the wall of the high just beneath the roof which will create a triangular gap on each side of the hive. It's best that the glass pane doesn't come into contact with the ground otherwise the scent from the hive will exhaust from the triangular gaps which will simply draw the wasps in. By raising the glass off the ground and as high as possible in relation to the landing platform, then scent from the underside of the hive will draw the wasps to the front of the pane and help confuse them.
Best of luck to all of you who are having problems.
Kind regards,
Karol