I don't know for sure, but I definitely like to think so...

Yes. Wasps are the primary pollinators of any number of flowering plants and trees. Ixora is the most common one. But I've seen wasps and bees working on Bismarck Palm flowers at the same time.

I've seen them in great numbers on my queen palms, crepe myrtles, and in my veggies garden. I rarely see a honey bee anymore.
john

I think the honeybees may all be in my yard - along w/ loads of other pollinators = )

Here is a link that might be useful: pollinator.com

Wasps help me pollinate in my screen-greenhouse and keep my wife (the plant killer) out of there. The wasps make a paper home in there but the bees cannot go in and out easily to where they live. Many squashes and melons etc. grow where I know for sure I haven't pollinated them. So yes they surely are pollinators.

Lou

Another great aspect of having wasps is that some of them are very predatory and will "take out" some of your garden pests. They are wonderful to have in your garden. Try to have something blooming all year for them, to make sure that they stay around.