Should I get rid of a small wasp nest?

Question

My girlfriend has been offered an insect hotel and we decided to hang it on our balcony (we live in an apartment close to the forest in Denmark). It has attracted wasps and they have started building a nest inside a cavity supposed to be used by butterflies (I can see it through the slit).

Right now it is not bothering because the wasps are few and very tame : they're not attracted by food, don't come inside and completely ignore anyone on the balcony. They just relentlessly fly in and out. The nest is small, roughly 6cm in diameter, and can't expand so much because the cavity is a cube about of about 10cm of edge length.

Should I get rid of it while it is still easy, or should I leave it alone ?

Answer 1

Wasps are just as beneficial as bees. Some plants are pollinated by wasps instead of bees. Carrots, parsley and their ilk are all Vespa or Ant pollinated (ants are descended from wasps).

As a beekeeper, I can recommend a few things. One, if they aren't really bothering you, then leave them alone. The nest will die off in the winter and you can clean out the insect house then.

Two, if they do bother you, then simply move the nest.

To move the nest, plug the entrance hole tightly with some grass early in the morning before the wasps are flying, and quickly move them to their preselected new location. If you are quick about it, you can move the nest without any wasps getting out. Once hung in its new home, just get away from the nest and let the wasps pull the grass out in their own. Trust me they are strong enough to do it in their own, don't help because you will get stung. Some will come back to the old location wondering what happened, but the activity of pulling the grass out slows then down from just flying out and losing their home. It forces them to slow down and take a look around a bit and realize they aren't in the same spot as they were before. Again, some will be stupid about it, but they'll either eventually find their way home again, or finally die off from starvation. (They need the brood in the nest to feed properly).

Answer 2

I would get rid of it now, because they'll only be harder to get rid of when they're larger and more aggressive. You won't want to use any poisons, obviously, because then you'd be hurting your good bugs.

You can do a couple of things. One is to just take a trash bag and put it over the whole thing and pull it tight. Maybe even tape the top shut. They'll eventually die.

If you want to be more human or get rid of them more quickly in general, do the same thing, but put them in your freezer for a day. Then you can safely clean out the nest.

If you're not worried about being stung, just knock the nest out that they're building. They may come back and even start to rebuild, but if you do it again, they'll move on.

If you want to go the chemical route, just don't spray the bug hotel. Spray them while they're in the air.

Answer 3

Many small wasps are beneficial, preying upon or parasitizing other bugs or grubs. I tend to attempt to let honey-bees and bumble-bees that have found their way into the house out, and kill wasps or yellow-jackets that have made the same mistake. Outside I normally leave well enough alone unless they are too near people. Without knowing what the behavior of your wasps may be, the described behavior sounds relatively non-threatening and I doubt the nasty ones that make football-sized nests would start inside a small sheltered location like that, but it's difficult to predict for certain.

It is certainly possible to simply rub out (or wash out with a stream of water) the nest when most or all of the owners are away from it, and that alone will often cause them to move on. If any are home, they will take objection to that behavior, but you can observe the activity and turn the pesticide-use advice (which tries to get them all at the nest by going early or late in the day) on its head and hit them mid-day, if possible on a cooler day when they will be a bit more sluggish.