I have a yard this year for the first time and I'm attempting various methods of building beds. For my first bed, I used double digging. But that was an insane amount of work and I'm not all that happy with the bed that resulted. I've been reading a lot of permaculture literature and they all suggest gradual bed construction through sheet mulching.
But I don't have that much organic matter readily available to me. About the only organic matter I have is a giant brush pile from a serious shrub trimming. The pile includes an entire box shrub, as well as trimmings of box shrub and yew. It also includes a large quantity of soft needle pine and tulip popular branches that came down in a storm.
I know pretty much all parts of a yew tree are toxic. Will that prevent it from working well in a hugelkultur? Will the toxin degrade or will it keep the yew from rotting and/or poison my soil microbes? Are there any woods that shouldn't be used for hugelkultur?