feeding soil

Asked September 30, 2015, 11:19 AM EDT

I am pulling together a number of organic materials to feed my soil; I won't list them all. I have lots of big trees. The needles fall everywhere. My question is … can I use the fir tree duff/needles as one of the components in my soil food mix? How about sequoia tree duff? My understanding is that pine and cedar duff and shavings would not be good. Thankx

Clackamas County Oregon

1 Response


I don' think there is a fundamental reason to not include this material in a mix of other organic components as a soil amendment. Conifer needles are acidic, and the duff from the Sequoia would be semi-woody, but if these materials are composted to some degree prior to use then the acidity would diminish (well-composted organic material has a more-or-less neutral pH) and the woody tissues, especially if they were chopped prior to composting, would be more suitable for incorporation. Although some plants do contain compounds that inhibit growth of other plants, these components break down during composting. You can read more about soil amendments with the OSU Extension publication EC 1561 "Improving garden soils with organic matter", which can be found at: