I was very excited about the prospects of experimenting with a food forest on my grandpa's old property up until I looked at the USDA's soil survey on the area. Apparently the entire property has a capability grouping of 7s (irrigated!), which to paraphrase the USDA's site makes it basically worthless for cultivating anything other than pasture. To make matters worse, the soil is highly alkaline (> or = 8 on the pH scale). Although I could introduce sulfur or pine needles to decrease the pH a bit, the fact that the entire valley used to be a sea bed makes me think that's one of those 'spitting into the wind' ideas.
I've been doing a lot of reading on improving soils with permaculture strategies, but I have to wonder what the limitations are for soil improvement. Is it smarter to just keep looking for a better patch of land?
What grows on the land now? How much land do you have? Where are you at and how much rainfall do you get etc? Unless you are in Death Valley, I would think that something could be grown there. Regarding the alkaline soil, I am pretty sure that there are some crops you could find that actually like alkaline soil. Another possibility is to use raised beds where you could tailor the soil to your own wishes, though this takes some time and effort.
Congratulations on your new land, keep us informed of your plans,
When I was a child my mother grew a productive vegetable garden in Jonestown, TX. The geological survey says you need several acres for a cow to free range. It's one quarter inch of soil topping pure kaliche there. As I remember it, the key to her success was digging a pit and then amending the soil there.
I can't say if it's the best choice in your situation, but it is definitely possible for permaculture practice to make even such poor soil into something better. If I were starting a food forest there, I would focus on establishing small areas and then expand them as the trees began to feed back into the system.
Trees are much easier to grow than annual plants. Trees grow everywhere. You see them growing up from a crack in solid rock. I'm certain you can grow things on your land.
As Casie said, I would make small areas of higher fertility first. I do it with tree guilds. It's pretty easy to build the soil in a circular area 20 or 25 feet across, put a tree in the middle, and support plants around it. Once you get one made, make another somewhere else. After you get some good soil built and some plants growing, the effects kind of snowball. Those established plants bring fertility, and wildlife, the wildlife adds more fertility, things grow better and drop more roots and leaves, and on and on it goes. Eventually your guilds will run into each other and you'll have your food forest.
I tried a quick google search for alkaline cover crops and the first hit was actually a link to this site! The thread here https://permies.com/t/51146/cover-crop-repair-barren-alkaline seems to deal well with some of the basics behind cover crops in dry and highly alkaline conditions. A quick look revealed cowpeas. Cowpeas are a great cover crop for dry conditions. They are frequently grown in the Sahel region of Africa, a region just south of the Sahara desert that can become somewhat fertile when (if) seasonal rains arrive. However, it spends much of the year hot, dry and dusty and many traditional crops just won't cut it there (especially in the northern parts, fairly close to the desert proper). Cowpeas are one of those rare plants that can hack the heat and dryness and not only survive but thrive all while fix nitrogen. It might just be as close to perfect for a cover crop in a dry and arid climate. My thoughts are that if it will work in the Sahel, it will probably work for you, but I am not exactly certain what part of the country you live in. That information could give us a better idea of what to suggest to you.
At any rate, I hope this is helpful to you, and as always, please keep us updated,
Thanks everyone for the wisdom and ideas! I really appreciate it.
@Eric: the climate is semi-arid and we average about 9.42 in of rain annually due to being in a rain shadow. As you can imagine, nobody dry farms here. We do have sun about 72% of the time as well, which is a lot of the reason I want more trees! As for my land, it's a little over an acre. Most of what my grandparents grew have died due to irrigation issues, except for a very hardy apricot tree, a struggling ponderosa pine, some juniper shrubs that don't care about drought, and quite a few russian olives that we plan to remove (they're considered highly invasive in the west). We think that the lawn areas are bermuda grass. I'd like to replace that too with either ecoturf or a cover crop blend for pollinators where lawn is actually needed. I'm a lawn hater :)
I have heard some great things about cowpeas and cover crops in general. Thanks for the link it's perfect!
Net and pan sounds like a great idea.
The net funnels a wide area of catchment to a same pan that is sunken+amended. So you can effectively get 5x the amount of rainfall. Amending it with carbon, soil life and aeration means it can store water for longer. Next is careful species and cultivar selection that are drought tolerant. Spinach family and some legume family, when it comes to annuals immediately pop up in my mind.
It certainly sounds like you are quite dry. Do you know if your ground is salinated from excessive irrigation in the past? If you need irrigation, I was going to suggest drip irrigation which is a far cry from sprinklers, center pivot or flood irrigation. Drip line only uses a very meager amount of water and only puts the water where you want it--by the plant roots. You tend to not get so many problems dredging up salts from below the earth because you never really soak down deep enough to get to those salts in the first place. I have good luck with dripline irrigation, but this is only my experience and this is something you will have to decide for yourself. Getting an arid weather cover crop could do wonders for you and the beauty is that they are multi-purpose crops. They (cowpeas) fix nitrogen. They loosen up soil, protect soil, and provide lots of good organic matter. This is even better if you can find at least one partner to go with the cowpeas that would act as a nitrogen sponge and soak up that nitrogen. A really deep-rooting cover crop can get minerals that are not on the surface plus condition that soil and work in carbon.
Congratulations on being open-minded to a cover crop. They can work miracles.
Fruiting olives are star performers where I live. I have three in my yard and they handle our rubbish soil like champions. Acacia willows, date palms, and chilean mesquites do well without amendment. Pomegranates.
I use those trees to help support life beneath. After some time doing this, I now have nectarines, apples, barbados cherries, and assorted citrus. Afghan pines. Beneath them I grow all manner of things as crops.
You would be amazed with what grows when you've got an active microbial community in your soil. Both bacteria and fungi help bring balance and assist plants to access what they need even if the PH is too high or too low.
Can you get woodchips for free? I'd start with a massive layer of wood chips across wherever you plan to grow things. Replenish annually (if not more frequently). Cover crop and experiment --- just rake back the chips and plant in the lovely soil below the chip layer. You may find that more grows than the "experts" say will grow.
While our soil isn't super high PH, it's still quite alkaline due to it being heavy grey clay. But with years of wood chips, you've got to dig down pretty deep before you hit that clay layer.
Compost, wood chip mulch, cover crop . . . and you'll get great soil in no time. Best of luck.
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