Interesting concept.
Looks like you may have to import them from the deciduous hardwood forests of the the northeastern areas of north America.
Maybe the Fruit tree areas around Medford chip up their fruit tree prunings? would those work?
Do tree services offer their chippings around there?
I doubt any around here in WA are willing to segregate their prunings and chippings.

Apparently, oak will work well, and there's a lot of it here. Getting tree trimmers to leave their chipped wood at my property will be a trick. I'd also have to know that a tree trimmer was going to be pruning and chipping an oak to begin with. I can get all the white fir I want, but it's the wrong type.

Why so fussy?
Any wood chips are better than no chips.
Mike

botann,

You didn't bother to read the paper did you? My reasons for wanting oak is specific.

No, I didn't read it. The link didn't work for me, and still doesn't.
Mike

Sorry about the link, botann. Try the link below. I bet you'll like the paper!

Here is a link that might be useful: ramial wood chips

The original link was invalid because of a space between the d and f in .pdf. Easy to spot and fix.

reading that study, the conclusions seem to be that the ramial chips are optimal-- but its not like pacific NW forest floors are barren wastelands. if you can't find oak, fir will work.

i would say that given the shorter time frames of a home landscape, if you had to wait a year or two to find the perfect chips, your garden will be worse off than if you just applied some fir chips tomorrow.

It's not about decay rates. From the paper:
" The best results are achieved with deciduous trees due the chemical structure of their lignin. Evergreens perform poorly, due to the transformation of their lignin by ëbrown rotsû which produce polyphenols and aliphatic compounds (Swift [1991], Larochelle [1993])...

SPECIES OF TREES TO USE
Some species are quickly digested (in few months) by the soil, others take a few years even if they
seem to have vanished. Coniferous trees, in cold and temperate climates, generate a blockage
mechanism of soil pedogenesis. Their lignin, once into the soil, evolves in producing a great amount of polyphenolic inhibitors. This type of lignin is also found in many tropical tree species but high soil temperatures break the inhibitor effect to some extent. In cold and temperate climates,
ramial wood from coniferous species must be avoided or restricted to 20% of the overall content.."

From another paper linked to below:

"Various forestry species under studies have shown that the best results were obtained with climax tree species, namely maple, oak, beech... having a high lignin content. The
tree species such as paper birch, poplar, aspen, have a lesser degree of efficiency. In the northern hemisphere,
conifers did not favour the formation of suitable agricultural soils. As far as, pine, spruce, and fir
are concerned, they cannot be used at a rate exceeding 20% of the total.."

Here is a link that might be useful: Paper #2 ramial wood chips

yeaaaa but, something about those papers seems really red flaggy. to me.

what happens when "rate exceeding 20% of total" levels are reached? total failure at that point?

i am more of a KISS kinda guy. for raised beds i go with straight compost. for perennials/shrubs i go with chips when i get them. else i use leaf litter/compost whatever is at hand.

What happens? nothing. imagine a bunch of wood like cedar that just does not want to rot. A forest of cedar would have a very very slow decay rate in the litter, minimizing abundant fertility as I seek it. This idea of some chips taking a century to degrade while some take a few months is actually the description of the process by which fertile soil is helped continously over long periods of time. Its not the one or the other, its the all together that creates robust long term low effort fertility.

This was all back in 2013 so I hope someone is still monitoring this post. Was wondering if anyone knows if you can purchase ramial mulch online of the type that will develop the type of fungus necessary for certain orchid seeds to grow, such as Orchis Italica and the white crane orchid?

I make mine from yard scraps, but a proper nursury could point you in a direction. Also you can ask Jason at Petals from the Past in Jemison, AL. He has a formal Botanical background, and he may even supply an Orchid nursery that was operating near me. I would consider the use of biochar too, as it will drain but be moist, and has this secret ability to suck oxygen out of the air and make it available to roots. I bet orchids would love it since they like dry feet.