Someone told me that in order to get thicker stalks, I need to fertilize. I have been "culling" my bamboo for several years and have gotten a few thicker stalks although now I am having trouble reaching the ones futher towards the center. Just can't get the handle of the saw through the hardened stalks! My original question though is, what type of fertilizer to encourage thicker stalks? And a secondary question is, any suggestions on cutting those stalks or should I just cut more to get to the center?