When do Lasius nuptial flights happen, and when is the best time to look for queens?
July to September! They peak around labor day, thus the name "Labor day ant", which is one of the best times to look for queens. In certain obscure populations, they can have flights well outside of that general timeline. Such as Florida, where Lasius neoniger have been recorded flying in December. Broadly speaking, though, it's July to September.