Just about any weapon will work. Though before I get bronze, I just use a flint ax because they always show up when I'm chopping trees anyway. They almost always go down in three hits, with the third hit doing double damage. The important thing is to make sure they're not all hitting you at the same time. Run a little bit to spread them out so you can take out one or two at a time instead of four or five.

If you're going to be in the area for awhile, dig a hole and use your shield to pop them in it. That will take care of the daytime spawns. And if you have to ask the question above, you shouldn't be in the black forest at night.