Depends on the wasp I guess..

Most species of gall wasps attack specific tissues of the host plant, forming galls, a type of defense response, on roots, stems, twigs, leaves, buds, or flowers. Salivary secretions from the wasp larva stimulate the plant to produce the gall, so the insect actually modifies the plant's normal response to injury, resulting in food and shelter for the larva. Many leaf galls are red and white and resemble miniature stars, sea urchins, cones, cups, or saucers.

-EverythingAbout.net
The Grim Reefer Reviewed by The Grim Reefer on . wasps help now it's fucking getting hot all the wasps are starting to get about & yesterday i found one on my plant & killed it. today there's 2 & they don't seem as monged so i can't kill them. help what can i do to get rid of them? cheers i've also got bud drying up there, i dont want them making a nest up there! Rating: 5