Infestation!

For the past two to three weeks, since the weather got nice and warm and we've wanted to have our windows open, Michael and I have been noticing that our apartment is infested with a multitude of tiny little beetles. Each is barely a few millimeters in length, and they don't seem to bite or to be interested in our food, but there's something disconcerting about having a small bug crawl across my arm when I'm sitting on the couch with book or trying to sleep at night. I'm a bit grossed out by them, to tell the truth. We have screens on our windows, but nevertheless these tiny invaders are finding their way inside. We suspect that they live on the cherry tree outside our kitchen window, as this tree is looking more and more chewed on as the summer progresses. We've taken to leaving the vacuum cleaner out and plugged in at all times. As soon as we can see four of these pests, we suck them up. A couple nights ago, we caught about 70 over the course of an evening. Anyone out there have a better way to get rid of small, unwanted and decidedly creepy beetles? I can see three of them crawling up the curtains as I type this! Icky!