It's called an Ivory-marked Longhorn beetle, Eburia quadrigeminata. It probably won't do a thing to your garden, but it may damage your trees - don't know for sure what trees these bore in, I think hickory, but a lot of species can be very destructive. Hope this helps.
Tucker

Found this info about your beetle at http://www.uvm.edu/albeetle/identification/index.html

"Adults are 0.5-0.9 inches long (12-24 mm.) Larvae feed in dry solid heartwood, of numerous hardwoods. This species is notorious for emerging from furniture and flooring after as many as 10-40 years."

Based upon my knowledge of the golden buprestid which has the same habit (may emerge from air-dried lumber many years later), it most likely infests recently dead trees. Further, it won't infest your house.