We have 20 acres in southern BC which goes up a mountain from about 700 meters to 780 meters. The area was selectively logged about 30 years ago.
The land is treed with Spruce Fir and Cedar mostly with an understory of various shrubs.
My question relates to the soil being acidic from the evergreens and am wondering how best to start a food forest. Should I try to get some cover crops growing in fairly clear area or start with some hugelkultur beds with heavy mulch to try to slowly build up a good soil or
Any thoughts and ideas most appreciated.
In extremely acidic soils in Scotland Sepp had great success using hugelkultur to help balance out the soil pH. The humus that is formed in the hugelkultur has an incredible pH buffering affect. This can help balance out both acidic and basic soils.
Cover crops and green manures are another great way to balance and stabilize soil conditions. If the soil is lacking nitrogen, then nitrogen fixers will be at a competitive advantage and will naturally balance this deficiency. If the soil has too much nutrient heavy feeders will be at an advantage and help balance this condition. So long as there is a large diversity of species in the cover crop mix it should help build and stabilize healthy soil conditions.
THanks Zach that's exactly the info I needed as I was sort of floundering with what best to do.
One last question is should I bring in a bit of top soil to start the hugelkultur beds or should I try to get a cover crop growing on them and chop and drop to get the soil built up,
Thanks for the help.
posted 5 years ago
In most cases bringing in top soil is not necessary. The humus of the hugelkultur enriches the soil and cover crops can balance out a wide range of soil imbalances. If the soil has been really beat up adding some vital soil can be a great inoculant. Either way it's much more ecologically efficient to grow fertility, as opposed to bringing it in. With this approach you have to be a little more patient. That said Sepp does not hesitate to add compost when it is easily or cheaply available. At the Holzerhof he uses the composted wood chip from power line pruners for his garden. It all depends on the cost (energetic and economic).
Water stable aggregates is comparable to humus in function. WSA are a result of microbial activity, pretty much microbe shit. They bind together soil particles, balance, ph, hold nutrients, and support the "architecture" of soil that allows for good water and gas exchange. Acidity in soil can be due to poor gas exchange, eg compaction. So you may want to check on your landscape for compaction. If it is i would suggested plants like lupin, chicory, salsify, dandelion, horseradish, rhubarb, mustard, parsnip, carrot, turnip, rutebega, beets... taproots, to help increase gas exchange. Leave the roots in the ground as much as possible and as they decay they will become little sponges that allow air to penetrate the soil. Leave em in the ground and check em next season, youll see what I mean. In terms of the WSA, if you get more microbe activity going than you will create more WSA and that will balance the acidity. Add microbe solutions, purchased, or ferment your own yarrow, nettle, horsetail, and comfrey (also you probably have a bunch of hanging lichens in the trees around you, probably a brown and green variety. Those are rich in nitrogen and promote cellular production in the soil and in fermentations so add that to!!!) add that mixture with the goal of microbes, not strictly nutrients.
Conifers do not only acidify the soil through the depsoition of there needles but by being so effecient at pulling nutrients out of the soil.... SO if you can keep nutrients in the soil by having a steady influx of them then your acidity should become balanced.
Promote those understory shrubs as much as you can, there decidouos leaves are of great value to your soil.
Chop and drop will be your best friend: Rhubarb, Burdock, Chicory, Sweet White Clover, Primrose, Comfrey, horseradish