These are European paper wasps.
(They look very similar to yellowjacket wasps but you can notice the antennae; they are brown here whereas they are black in case of yellowjackets. There are other subtle differences too.)
See this post on Gardening & Landscaping stackexchange about getting rid of wasps.
(This part is probably not really on-topic here ...
These are probably cockroach cases, or oothecae, that may contain up to 50 eggs, depending on species.
It looks like they are oothecaes of German cockroaches.
You can read more about baby cockroaches here.
According to the pest control expert, the ants are likely pharaoh ants. It matches the description on the Wikipedia page in all respects:
Pervasiveness in indoor environments throughout the world
He is treating the problem in my unit and a neighbour's unit using Maxforce Quantum. It could take some time :( .
This is not conducive to a ...
Stay vigilant. As you've noticed, once wasps get established in an area, they'll reproduce and spread out. Continue to watch for and eradicate nests. Hardware stores will sell a variety of chemical sprays, but a mix of liquid soap (dish detergent) and water works just as well.
Use wasp traps to prevent wasps from establishing new nests in your area. You ...
The species name of this insect is the gooseberry saw fly. There are three related species, I think this is the pale spotted gooseberry sawfly because it has a pale green head. They usually have black dots as well, but this might develop when the larvae grow. At least, this is what I observed once in my garden.