Cedar is in fact good for repelling insects. At least the ones I encounter here in Texas. When I see ants near my tarp, tent, blanket (whatever I am sleeping in/on) l cut a fresh cedar branch (with foliage still attached) and toss it on the ground near the ants. Ten minutes lates, no more ants. If mosquitoes get to be a problem I throw a green branch on the fire. Couple minutes later and no more mosquitoes. My favorite place to hike and camp is a varitable cedar forest. There are so many excellent uses for the various parts of a cedar shrub/tree that I could easily devote an entire thread to it.