Composting madrone leaves
Can I put madrone leaves in my compost bins? Will they deplete anything in the pile?
Josephine County Oregon
Thanks for your question about composting madrone leaves. The simple answer is: "yes, but...." The reservations about composting this particular leaf is that it has been described by some composters as "like giant potato chips." (That's not a scientific term; it just describes their consistency, which is tougher than other types of tree leaves such as maples, for example.) So, they don't break down easily, and you may find them looking undaunted six months from now. One way to deal with that, as with other tough and fibrous organic matter, is to shred it before adding to the compost pile.
The second "but" is the general rule that you should never compost any organic matter that is clearly diseased (fungus, discoloring from a cause other than fall temperatures and shorter days, or insect infestation), since many insects and pathogens overwinter in that tissue. Since the composting temperatures are much lower than during the summer, the internal temperature of the compost bin or heap may not reach high enough to kill these, and they will be a problem in your garden in the ensuing seasons.
In answer to your 'depletion' question, here's a link to an article by Dr. Linda Chalker-Scott, WSU, about the science of depletion of nutrients (one type of phototoxicity, or damage to a plant by something the plant is exposed to) in the use of mulch in gardens.
Here's a link to article on the composting process, which might answer other questions. Hope it's helpful!