Chewing the wall

For the past week, the weather here has been really terrible and gross, and we haven't been able to go for decent walks. During this time, I've been catching our pup chewing on small pieces of wood. I didn't think much of it the first couple of times, sometimes we come home with some of debris stuck on our feet. However, every day I've been catching her chewing on wood.... lo and behold I find out she is chewing pieces off the wood moulding! It's so weird, she's never done this before. I've been trying to play with her more and train her a new trick to keep her engaged, but I feel it might not be working. Has anyone dealt with this before? Could she be bored? Now enough things to chew on (she has rawhides and one of those real marrow bone things at the moment)? I hope to stop soon, I don't want her to get sick. I've sprayed the area with a good douse of bitter apple spray, and every time she's wandered in the suspected area, I've very loudly and sternly bellowed "Get away from there!" Is there anything else I could do?

Maybe I have to invest in a doggie pancho and rainboots... LOL

Thanks for any suggestions and advice.