Screen house a necessity in Toulumne CG in July?

Planning to camp there middle of next month. I figure the mosquitos are going to be in full force, would rather not spend all my in camp time huddle in the tent or covered in deet. Been looking at screen houses and they aren't cheap. It seems as though a lot of the CG will have standing water from all the snow melting, how many of you camp there in early summer have screen houses? What do you do about the bugs if you don't?

I can't advise you on TM and mosquitoes in the Spring, but you're right that a quality screen house will cost you
some $. There are several good models out there, myself, I bought a Eureka Northern Breeze several years back.
What I like about this model that many screen houses lack: a full zip-down cover over each of the screen walls (that
also double as awnings as well, poles are included for this). If you ever are sitting in the screen house in a driving rain
storm, the zip-down storm flaps come in handy. In the USA, they only sell the Northern Breeze 12 x 12 ft. model,
so I ordered mine from Canada, where they also sell a smaller 10 x 10 ft. size (which fits better in some of the tighter
campsites in Yosemite Valley). I love it, very well made, and great for the Spring, Summer and Fall.