Author Topic: Let's Talk Soils!  (Read 666 times)

Andrew Barney

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Let's Talk Soils!
« on: 2019-11-03, 03:44:02 PM »
Hey All, I've been planning on starting a thread on this for a while. I've been learning a lot about soils in my Introductory Soil Science class. So much useful information that i'd like to talk about, share, and discuss. I plan on posting to this thread on several soil related sub topics in the near future, but i'll start simple first.

First, if you live in the U.S. there is a nice and neat handy reference for identifying your soil on your property and some of the defining characteristics that go along with it. This information easily translates into how well your soil retains water, what nutrients may be lacking or bound up by soil structure or pH, and other things that translate to gardening, farming, and plant breeding. I never realized how much this affects and how crazy important knowing some of this may be. For example, this year i tried planting some squash but they did terrible. It has now come to my realization that they did so pitifully because they had iron deficiency. Apparently this is a common problem in my area because the pH is so high. At high pH iron becomes unavailable.

Use the following link below to use the USDA soil survey map. You will need to create a square AOI around the property before you can use the soil tools on it.
https://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx

I was able to use it to compare the soil at my parents property with the soil at the new house we are renting. I was surprised by the differences, though overall they are very similar. Though the new house will need two raised planting beds for garden space so the natural soil is not of much concern except for shrubs.

My soil pH is pretty high. Around 8. My natural soil organic matter is pretty low about 1.5% which is pretty common for out west.

But the main soil around here is Fort Collins Loam and with a pretty alkaline pH. Low rainfall, lots of calcium carbonates, the clay portion is pretty reactive.

FORT COLLINS SERIES

The Fort Collins series consists of very deep, well drained soils that formed in mixed eolian sediments and alluvium. Fort Collins soils are on terraces, hills, plains, and alluvial fans and have slopes of 0 to 10 percent. The mean annual precipitation is about 38 centimeters (5 inches) and the mean annual temperature is about 8 degrees C. (47 degrees F.)
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aridic Haplustalfs

TYPICAL PEDON: Fort Collins loam - grassland.

RANGE IN CHARACTERISTICS:

Mean annual soil temperature: 8 to 13 degrees C. (47 to 55 degrees F.)
Mean summer soil temperature: 15 to 22 degrees C. (59 to 72 degrees F.)
Depth to the base of the Bt: 28 to 76 centimeters (11 to 30 inches)
Depth to calcareous material: 20 to 51 centimeters (8 to 20 inches)
Organic carbon upper 38 centimeters (15 inches): ranges from .6 to 2 percent (weighted average .8 percent)
Average sand/clay ratio: 1 to 3
Base saturation: 90 to 100 percent
Rock fragments: 0 to 15 percent, (typically less than 5 percent)
Moisture control section: not dry in all part for more than 1/2 of the time that the soil temperature is above 5 degrees C. (41 degrees F.) (moist in some or all parts during May and June)
Moisture control section: not dry for 45 consecutive days following July 15.

GEOGRAPHIC SETTING:
Parent materials: alluvium (may be modified by a thin mantle of eolian deposits)
Landscape: terraces, hills, plains, or alluvial fans
Slopes: 0 to 10 percent
Mean annual precipitation: 33 to 43 centimeters (13 to 17 inches)
Mean annual temperature: 7 to 12 degree C. (45 to 53 degrees F.)
Mean summer temperature: 14 to 21 degrees C. (57 to 70 degrees F.)

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Runoff: medium
Saturated Hydraulic Conductivity: moderately high

USE AND VEGETATION: These soils are used as native pastureland and as dry and irrigated cropland.
Principal irrigated crops are small grains, alfalfa, corn, sorghums, and sugar beets.
Dryland crops are limited primarily to winter wheat.
Native vegetation is blue grama grass, wheatgrass and some buffalo grass.

DISTRIBUTION AND EXTENT: Eastern Colorado, Montana, and Wyoming. The series is of large extent. MLRA 67

----

The new house we are renting has HELDT.

HELDT SERIES

The Heldt series consists of very deep, moderately well drained, moderately slow to slowly permeable soils that formed in fine textured alluvium on fans, terraces, and piedmonts. Slopes are 0 to 25 percent. The mean annual precipitation is about 13 inches, and the mean annual temperature is about 48 degrees F.

GEOGRAPHIC SETTING: The Heldt soils are on fan remnants terraces, hillslopes and alluvial fans. Slopes range from 0 to 25 percent. The soils formed in fine textured alluvial sediments derived primarily from sedimentary rock. The average annual precipitation is 10 to 15 inches with over half falling in the months of April, May, and June. The average annual temperature is 44 to 48 degrees F. The frost-free season is 110 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Orella and Samday soils. Orella and Samday soils have bedrock at depths of less than 20 inches.

DRAINAGE AND PERMEABILITY: Well or moderately well drained; slow or very slow runoff; slow to moderately slow permeability.

USE AND VEGETATION: These soils are used principally as native pastureland, although they may be tilled to both dryland and irrigated crops in some localities. Native vegetation is primarily western wheatgrass, green needlegrass, blue grama, and basin wildrye.

DISTRIBUTION AND EXTENT: Central and northern Wyoming, southern Montana, and northern Colorado. The series is of moderate extent.

« Last Edit: 2019-11-03, 04:07:29 PM by Andrew Barney »

Andrew Barney

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Re: Let's Talk Soils!
« Reply #1 on: 2019-11-03, 03:47:40 PM »
more pics.
« Last Edit: 2019-11-03, 03:49:27 PM by Andrew Barney »

Andrew Barney

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Re: Let's Talk Soils!
« Reply #2 on: 2019-11-03, 04:24:58 PM »
something that has really stood out to me is how much calcium carbonate i have in my soil. This goes back to the blossom end rot i have seen when i was doing some domestic tomato trials and more often in the early (oblong) watermelon landrace fruit. Some tomato varieties have more blossom end rot more than others (often the oblong Italian types). Traditional gardener wisdom say's that your plants need more calcium, so add calcium and it will go away. That might actually work, but in my climate i already have lots of calcium, i shouldn't need to add any more. What it really means is that in those cases the plant is not getting enough calcium because of some other reason, such as possibly over watering and saturated soil, shallow root genetics, or the calcium is too deep in the soil (maybe tilling could fix that temporarily).

Either way i have adopted Joseph's strategy for this problem and i think it is working quite well. I don't want puny plants so i am not saving seeds from plants that exhibit blossom end rot. So for whatever reason i am probably selecting for roots that go deeper or are better at scavenging calcium, or other traits which help in this regard rather than changing the soil when it does not need to be changed. For other things changing the soil may be worth it, but i don't think this is one context which does.

reed

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Re: Let's Talk Soils!
« Reply #3 on: 2019-11-04, 04:13:13 AM »
I never knew what blossom end rot was till I joined the forums. I do remember seeing it years ago but I just threw those plants away. That's what I do with pretty much anything that doesn't grow good.

I'v never even had a soil test, I don't want to know the technicals about my dirt or what preferences a particular plant has related too it cause I know I'm not going to do anything about it anyway. The dirt I have is the dirt I have for the most part.

I'v always added lots of stuff like leaves, weeds, spent vegetable plants, some occasional wood ashes and chicken poo.  There is a noticeable difference between my old garden with 25 years of that treatment and the new one with just 5 years, so I guess I have changed it over time but never specifically for this crop or that one.
« Last Edit: 2019-11-04, 04:16:34 AM by reed »

Natasha Flue

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Re: Let's Talk Soils!
« Reply #4 on: 2019-11-04, 05:13:23 AM »
something that has really stood out to me is how much calcium carbonate i have in my soil. This goes back to the blossom end rot i have seen when i was doing some domestic tomato trials and more often in the early (oblong) watermelon landrace fruit. Some tomato varieties have more blossom end rot more than others (often the oblong Italian types). Traditional gardener wisdom say's that your plants need more calcium, so add calcium and it will go away. That might actually work, but in my climate i already have lots of calcium, i shouldn't need to add any more. What it really means is that in those cases the plant is not getting enough calcium because of some other reason, such as possibly over watering and saturated soil, shallow root genetics, or the calcium is too deep in the soil (maybe tilling could fix that temporarily).

Calcium is water soluble and hangs out in the soil solution with Potassium and Magnesium. So if there is under or over watering at critical times like fruit set and early growth, the calcium won't get taken up by the plants because the water uptake isn't optimal. Generally, it is underwatering that I've seen it and it happens in peppers as well, although the spot is usually on the side of the fruit. Most gardeners don't test their soil, but if they're putting down compost, they should have enough of everything to grow plants decently. I think even with commercial farmers, the blossom end rot I've seen has been water issues rather than nutrient issues.

The only other thing that could possibly happen is that the ratio of K:Ca:Mg could be out of wack. This is when soil testing is good. You'll see it show up as more calcium needed in a soil test and depending on what you pay for, you'll get the ratio as well. But generally we only look into this if the grower has been watering adequately and there isn't an obvious irrigation issue earlier in the summer.

Your strategy is a good idea, you'll select for more resilient plants. Some varieties are more susceptible to blossom end rot and presumably have less resilience to water variation.

Richard Watson

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Re: Let's Talk Soils!
« Reply #5 on: 2019-11-10, 11:24:26 AM »
Ive had soil tests done, not just the garden but over the whole block of land which has shown the PH to be consistent at 6.7, calcium levels were good but my soil and pretty much over all the South Island lacks in boron and selenium, I added these two elements to the garden soil a number of years ago and the levels still appear to be ok for now. Looking at the soil pyramid chart Andrew posted I would describe my soil as slit loam but would be nice if it were more a clay loam, I'm working towards that by adding a clay/slit subsoil to my compost system. I have a watercourse channel that crosses through or property, it only flows after major rain events which flows out from a nearby river, this river carries a lot of clay/slit from the mountains when in flood, this seeps into the half metre deep soil within this channel, the top half of this soil is used by screening it and using in pots while the bottom half that sits about the underlying shingle is what's added to the compost   
Changeable year round climate with warming winters - just under 500mm average yearly rainfall. 20 years of soil improvements plus sub soil top soil reversal means my garden beds are about half metre deep. Below that is 100's of metres of alluvial out wash from the Southern
alps.

William S.

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Re: Let's Talk Soils!
« Reply #6 on: 2019-11-10, 01:09:13 PM »
My soil began with glacial lake Missoula an ice aged ice dam giant lake that once flooded this valley. The glaciers carvedthe mountains and ground quite a lot of dust from them. This settled on the lake in the form of clay and silt and sunk to the lake bed. My current garden's soil is called something like Round Butte silty clay loam and is just a 7 inch plow layer, a 7 inch clay accumulation layer, and a deep deposit of increasingly less differentiated material that quickly becomes lake bed sediment parent material. Near the house I have a much deeper soil with more silt but similar origins. Adding local sand to this soil seems to work very well for me. I buy a ten yard truck load or two each year. Spread it on the garden as mulch and then rototill it in as I need to control weeds or plow under a garden. I've added about four loads or more just to the 1/10th acre fenced garden and I imagine two more loads wouldn't hurt it.
Western Montana garden, glacial lake Missoula sediment lacustrian silty clay mollisoil sometimes with added sand in places. Zone 6A with 100 to 130 frost free days

Doro

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Re: Let's Talk Soils!
« Reply #7 on: 2019-11-13, 07:55:46 AM »
This reminds me of my first year gardening at our house. I dug into the lawn, excited to start the first garden beds... found an inch of top soil above orange sand... just flipped the grass back up and went hiding from the gardenproject for a while lol it was the worst I had ever seen. Like a kids sand box.
I never did a proper laboratory soil test, they are rather pricy here. But I did a simple mud jar test and found it to be 90% gritty sand, a little silt, no clay and very little organic material. The water in the jar had cleared up in a day.
Found out that the natural dirt on my property is early deposited  glacier sand with plenty of iron, a bad deficiency in lime and a PH of 5.4
I've been adding compost, mulch, garden lime, ashes, chicken and rabbit manure ever since. Things have improved a lot in the older garden areas. However I'm adding new garden beds almost every year. It is very interesting to compare the oldest areas with newer areas, it's quite a jump in soil quality.
It is fascinating to see how much time it takes to build up organic material in soil. There never seems to be enough compost and garden waste. But I finally found a small sawmill that is happy to just get rid of their bark chip ;D this should speed up the soil building somewhat.

Richard Watson

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Re: Let's Talk Soils!
« Reply #8 on: 2019-11-13, 09:46:03 AM »
How easy would it be to bring in clay as well Doro
Changeable year round climate with warming winters - just under 500mm average yearly rainfall. 20 years of soil improvements plus sub soil top soil reversal means my garden beds are about half metre deep. Below that is 100's of metres of alluvial out wash from the Southern
alps.

William S.

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Re: Let's Talk Soils!
« Reply #9 on: 2019-11-13, 10:20:16 AM »
Or clay topsoil or clay loam topsoil?

Note: some unscented kitty litter is clay.
Western Montana garden, glacial lake Missoula sediment lacustrian silty clay mollisoil sometimes with added sand in places. Zone 6A with 100 to 130 frost free days

Doro

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Re: Let's Talk Soils!
« Reply #10 on: 2019-11-14, 06:11:16 AM »
I could order top soil with clay at the 'truck central', they sell top soil of all kinds from building sites. Should be in the garden budget. But you never know what you'll get with it... in terms of possibly harmful stuff for the garden. Soil pathogenes, weed killers, weeds, invasive species of slugs or plants... I heard so many horror stories that it does not feel safe to buy dirt there.
The kitty litter is a brilliant idea. I'm actually buying an unscented bentonite one, but have not thought of it as valuable clay source. Got to do some reading on that subject.

William S.

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Re: Let's Talk Soils!
« Reply #11 on: 2019-11-14, 07:56:12 AM »
This is a weird thought I've had but silt is the tough one to buy. I don't know of a source for pure silt. Unless buying topsoil. If soil minus humus is sand, silt, and clay and an optimal loam a nice mix of the three than if building a soil from components it would be nice to buy silt.

In square foot gardening you just build an artificial soil horizon of vermiculite or perlite, peat, and compost. So it is mostly just organic matter. Vermiculite struck Mel Bartholomew as a magical additive, light weight, sand sized, but with clay like properties. Would imagine it decomposes to clay by weight but loses volume.

Sometimes Bentonite is sold in bulk as a pond liner material. Fun Montana soil fact it's named for Fort Benton Montana. It's an expanding clay though so has some unusual properties as a soil component.

I add my sand addition as kind of an artificial soil horizon and I think there is something to be said for using soil additives on the surface. Think Pat Lanza style lasagna gardening. Sheet compost, then use a layer of something like sand, topsoil, potting soil, as a top dressing to plant into. So if adding a non-organic substance like sand, silt, clay, vermiculite, perlite, pot shards, pumice, or kitty litter that could be mixed with peat, composted ground bark, composted nut shells, composted sawdust, compost, coir, or leaf mould and then form a layer that you can directly plant into. Or you can just add whatever you have as a mulch.

I wonder sometimes what I would do if I had time and no money for sand. The the soil on my hill is actually sandier. I think if it came down to it I would harvest topsoil from the hill to add to my garden. If I ever did so I would pick a patch with lots of annual weeds, then probably just take a shovel full then leave a space before another shovel full. It would leave the ground pock marked but I think able to recover. The pocket gophers would eventually level it again. Not sure how much it would impact grassland productivity if I ever needed to graze it. Though grazing animals might help even out the ground surface again. If I gardened on my grandfather's farm there are places where soil has left wheat fields via water erosion and accumulated on adjacent grasslands. If you needed topsoil for a project it would be possible to mine those accumulation areas.

The ancestry by which I got my last name supposedly left Switzerland and came to the United States because he was tired of hauling soil by hand back up the hillsides of his farm.

Another thought is that if two gardeners one with too much sand and another with too much clay lived nearby they could literally just swap soils. On a large scale I think a skidsteer rental for a day could move a lot of material.

I was intrigued to realize recently that the How to Grow More Vegetables book does recommend sand and clay addition if necessary. It suggests only adding an inch or two of material though and only doing it once. So a very conservative amount of material which is reasonable considering their methods are all hand work. Without a motor vehicle even buying a bag of potting soil and getting it home is going to be a big deal. So finding the nearest sand or clay deposit and using a wheelbarrow might be an option- like my idea of borrowing soil from my hill.

One thing to do with soil of dubious origin might be to pile it somewhere and wait a few years. If the main concern was residual persistant herbicides. Another might be to add material to a compost pile.

I've had a lot of curiosity about using charcoal as a soil additive ever since I became aware of biochar. Though my actual additions have been minimal and far between. It makes since to me in terms of longevity. Same with sand, once added it's permanent.

Hugelculture is fairly popular and I have a pile of spoiled untreated lumber that's partially rotted.

I'd like to sort of do a demonstration area of a number of popular soil improvement techniques with a different one for each bed in the area. Though it seems a pretty long term concept. I did double dig one small bed with my son this year. Will see how it does next year. I think balancing amount of work involved with results is pretty critical so mostly I just stick with what's been working for me. Which is mostly the sand addition. I fiddle around a little though as one does.
« Last Edit: 2019-11-14, 09:24:16 PM by William S. »
Western Montana garden, glacial lake Missoula sediment lacustrian silty clay mollisoil sometimes with added sand in places. Zone 6A with 100 to 130 frost free days

Doro

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Re: Let's Talk Soils!
« Reply #12 on: 2019-11-15, 06:30:01 AM »
Bio char aka terra preta works great and helps a lot with nutrient and water buffering capacity in acidic sand soil. One of my potato beds is a mulched terra preta bed, really love how it works.
I'm also adding char to my compost bin. A layer in the bottom catches runoff and charges the coal at the same time. Some char inbetween on occasion also helps to keep it from becoming too soggy.

Bentonite clay is a fascinating subject. There are different kinds of it and not all of them are suitable for gardening. Agricultural bentonite is calcium bentonite. The pond liner that swells a lot is natrium bentonite or natrium enriched calcium bentonite, not ideal for growing plants because of adding too much salt for most soils. It seems to be easy to get calcium bentonite for sand soil improvement in many countries, but Sweden is not one of them. Found one product 6kg for almost 500 SEK (around 50 USD) + postage. That's silly.
Which brings me back to the bentonite used for kitty litter lol. The gardening relevant part in bentonite is the Montmorillonite, the higher the content the better. Non clumping litter has less Montmorillonite in it than the clumping one. Calcium bentonite and natrium bentonite are both used, possibly even mixes of them. But only a few brands are actually telling the customer which kind is used in in their product.
However it should be possible to tell the difference at home by checking how much water the litter absorbes. Calcium bentonite absorbes and swells less, about 1,1-1,4l water/kg litter. Natrium bentonite absorbes 1,4-4l water/kg litter (impressive!)
So for soil amendment it will be best to look for unscented clumping litter that absorbs ~0,1l per 100g. Probably the cheaper noname products with customer reviews mentioning that it is not absorbing enough kitty business.
The cheap no name clumping litter that I have at home is absorbing about 0,1l of water per 100g litter. Just tested that. It seems usable for the garden and it should work to spread cat litter with a regular spreader cart without being too messy... at least on a dry day.
I think I'll do a test run about good ratios for my soil. There are some pepper starts from an F3 that need repotting.

Richard Watson

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Re: Let's Talk Soils!
« Reply #13 on: 2019-11-15, 12:08:44 PM »
My soil amendment is through making compost which ends up being a bit like Hugelculture because of the large amount of rotten and half rotten wood that makes up the end product. The first photo on the left is the start of the log maturing, I'm fortunate to have a resource of wild pines which are regarded as a pest species in NZ, the top 70% of the tree is used for firewood and the bottom which is tough splitting is for compost. The middle is a load of top soil blocks that I'll going to dry, once drier I drop them on the ground and most of the soil will fell off, there's a lot of cooch grass rhizomes in these so once most of the soil has been shaken out I leave it under the covers on the right for a couple of years, once the rhizomes become quite crumbly it becomes worm tucker in the compost system.



The subsoil is used covering the compost


The other end of the log maturing circuit. This end the logs are about 6 years old, all I have to do is smack it with the side of a pickaxe and they just fall to bits then its added to the compost that also circulates following logs. The compost system add one end - take from the other, no turning it over, just letting the worms do all the work. When adding to the compost its important to add garden waste correctly, rootcrops that would regrow are added at ground level, leaf material on top stacked high enough so that anything that can grow gets buried deep.





Changeable year round climate with warming winters - just under 500mm average yearly rainfall. 20 years of soil improvements plus sub soil top soil reversal means my garden beds are about half metre deep. Below that is 100's of metres of alluvial out wash from the Southern
alps.

William S.

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Re: Let's Talk Soils!
« Reply #14 on: 2019-11-15, 05:15:58 PM »
Stated in meters Richard’s soil depth sounds impressive to my English unit ears. A half meter is 1.64 feet which is 19.68 inches. John Jeavens recommends 24 inches of double dug depth in his famous method, so Richard is still about only to about 82% of that arbitrary goal after twenty years of effort. Unless about a half meter could be 60% of a meter which is almost precisely what John recommends. I wonder what your starting conditions were regarding soil type, and depth?
In my sand amended beds inside the fenced garden where the most substantial soil improvement has occurred, I can just barely reach the clay accumulation layer with my 14-inch Meadow Creature broad fork. Only in the beds themselves though, the pathways would be much shallower. I started with approximately 7 inches of topsoil. I started in 2011 but have only gardened there 6 of the years in between. Though I’ve added enough sand in that area that if I thoroughly double dug the beds to 24 inches and mixed the soil, they might be 20% sand. I’m curious to continue gardening but if I could garden continuously for the next 14 years, I might be able to match Richard’s feat- or not! Or I could just move my garden to a different soil.

Ways soil quality matters for crops:
NPK and micronutrients: If these aren’t well balanced and in available forms, we get nutrient deficiencies. This can also affect which crops do well in each area.
Clay, sand, and silt content. This affects the soil quality greatly, but we recently discussed it. Let’s just say that ideal soils are loams with a good mix of the three.
Though one other physical component exists: Rocks- these can get in our way physically while we garden. Think giant rock piles when gardening/farming in glacial till.
Though one key part of this particle size equation is water storage capacity, root penetration, and clay accumulation layers or in deserts caliche deposits.
Total depth of quality soil: top 7 inches on average of my native soil is quality. In some places less, in some much more. With sand addition it improves. Until you get to that clay accumulation layer, rock layer, caliche, and so forth.
Germination ecology: Some plants will not germinate in some of the soil textures mentioned above. California chia seems to require sandy soil specifically to volunteer and persist. I’ve seen horse chestnut and pine only germinate in certain soil textures.
Soil compaction layers. How we treat soil mechanically, and how its been treated in the past by others including even biotic events like cattle trampling.
Organic matter content. Soils can range from 0 OM to 100% OM think pure sand on a continuum to pure peat moss.
Chemical composition: Type of clay, type of parent material rock.
PH low to high
Salt content: Salt can come from irrigation water and accumulate in soils, it can rise up from saline aquifers, it can be indigenous to a soil.
Chemical contamination: Too much of some micronutrients added can be a bad thing, fertilizers can contain small amounts of toxic substances, microplastic, regular plastic, pesticides including herbicides, fungicides, insecticides, and rodenticides especially when environmentally persistent. Chemical wastes, persistent industrial chemicals in aquifer and surface waters, and acid mine drainage or persistent contamination from mining such as mercury and lead deposition.
Trash contamination of soils: glass, plastic, batteries, wire, steel cable, shells, pottery, bones, various metals, old vehicles, and old farm equipment. Old trash burn piles, asphalt chunks, concrete chunks, old treated posts, old medical waste, and old open dumps.
Physical holes like from tree spades, old mine test pits, mining for sand, old basements, and old wells.
I read a story once in a plant ecology text where I think in Australia there is a soil type with a relatively low value economically plant community that if you clear it and plant a crop for a few years the soil eventually subsides and becomes a saline lake. I.E. using the soil for anything other than the native plant community ultimately destroys the land completely.

What can be addressed through plant breeding?
Shorter parsnips for heavy soils
More drought tolerance
More salt tolerance
Preferences for unusual soils – one population of California chia grows on very unusual soils in Southern Utah, a rare camas species grows in serpentine…

What must be addressed through soil improvement?
Can we grow crops in extremely shallow soils?
Extremely rocky?
If climate change forces us north can shallow northern soils support agriculture?
One example from sagebrush steppe: Very low OM, but structurally can be ideal loams for agriculture with a good mix of Clay, Silt, and Sand. With massive irrigation projects extreme agricultural productivity can follow.


Potential for breeding for extreme soil conditions and limitations in tomatoes: Tomatoes have extreme potentials in the ~14 species tomato complex for drought tolerance, elevation tolerance, tropical tolerance, and salt tolerance. Realizing these potentials might best be done with new domestications in some instances.
I grew a population of my 2019 tomatoes without irrigation direct seeded. Ordinary domestic tomatoes performed best. The soil was variable. In the worst soils those with the most shallow and heaviest soils germination was poor and plants showed drought stress the worst. They grew poorly and slowly. When I amended the soil for one plant with a bag of potting soil, organic fertilizer, and sand, it grew very well afterwards and ultimately produced some seed. Pulling it up, it was clear it grew roots into the new layers. Fortunately, it rained enough to allow it to recover.
Some wild tomato species are far more xeric than domestic tomatoes, though I am not certain if any of them are adapted to shallow heavy soils.  Solanum penellii for instance is said to grow in dry stream beds. These tend in my experience to have sandy gravelly to rocky soils with lots of variable deposition layers, and potentially a subsurface stream flow at some depth. The sort of environment where deep rooted crops like grapes naturally grow. So, I suspect that a quality soil structurally such as a deep loam would still be important for extremely salt and drought tolerant tomatoes.
Then there are some other aspects beyond soils, but which affect soils: Proximity to volcanoes, rainfall amounts and patterns, number of frost-free days.
Climate change: rapid change and unpredictable garden conditions may affect what we can grow where, if we can continue to grow traditional crops in traditional soils, and if we can continue to utilize a full growing season. I.E. 120-day corn if you only have 60 days’ worth of water.
Here is some soils data for me from the NRCS Web Soil Survey:
Here is the soil my garden is currently on:
“145—Round Butte silty clay loam, 2 to 4 percent slopes
Map Unit Setting
•   National map unit symbol: 4vxp
•   Elevation: 2,000 to 3,200 feet
•   Mean annual precipitation: 10 to 16 inches
•   Mean annual air temperature: 39 to 45 degrees F
•   Frost-free period: 100 to 130 days
•   Farmland classification: Farmland of local importance
Map Unit Composition
•   Round butte and similar soils: 85 percent
•   Minor components: 15 percent
•   Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Round Butte
Setting
•   Landform: Lake plains
•   Down-slope shape: Linear
•   Across-slope shape: Linear
•   Parent material: Lacustrine deposits
Typical profile
•   Ap - 0 to 7 inches: silty clay loam
•   Btn - 7 to 14 inches: clay
•   Bkn - 14 to 44 inches: silty clay
•   C - 44 to 60 inches: stratified silt loam to clay
Properties and qualities
•   Slope: 2 to 4 percent
•   Depth to restrictive feature: More than 80 inches
•   Natural drainage class: Well drained
•   Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr)
•   Depth to water table: More than 80 inches
•   Frequency of flooding: None
•   Frequency of ponding: None
•   Calcium carbonate, maximum in profile: 15 percent
•   Salinity, maximum in profile: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm)
•   Sodium adsorption ratio, maximum in profile: 60.0
•   Available water storage in profile: Low (about 5.6 inches)“

Here is a different soil I could garden on land my parents own if I built or could have a deer fence built:

“130—Polson silt loam, 0 to 2 percent slopes
Map Unit Setting
•   National map unit symbol: 4vwz
•   Elevation: 2,400 to 3,500 feet
•   Mean annual precipitation: 14 to 19 inches
•   Mean annual air temperature: 39 to 45 degrees F
•   Frost-free period: 105 to 135 days
•   Farmland classification: Farmland of local importance
Map Unit Composition
•   Polson and similar soils: 85 percent
•   Minor components: 15 percent
•   Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Polson
Setting
•   Landform: Stream terraces, alluvial fans
•   Down-slope shape: Linear
•   Across-slope shape: Linear
•   Parent material: Glaciofluvial deposits
Typical profile
•   Ap - 0 to 10 inches: silt loam
•   Btn - 10 to 18 inches: silt loam
•   Bkn - 18 to 60 inches: silt loam
Properties and qualities
•   Slope: 0 to 2 percent
•   Depth to restrictive feature: More than 80 inches
•   Natural drainage class: Well drained
•   Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr)
•   Depth to water table: More than 80 inches
•   Frequency of flooding: None
•   Frequency of ponding: None
•   Calcium carbonate, maximum in profile: 15 percent
•   Salinity, maximum in profile: Slightly saline to moderately saline (4.0 to 8.0 mmhos/cm)
•   Sodium adsorption ratio, maximum in profile: 30.0
•   Available water storage in profile: Moderate (about 8.7 inches) “

I think from this, you can probably see that there might be some advantage to me someday building a fence around the unused two acres of the second soil type on the edge of my parent’s hayfield and moving my garden operation four miles. Though there are tree spade holes.
Western Montana garden, glacial lake Missoula sediment lacustrian silty clay mollisoil sometimes with added sand in places. Zone 6A with 100 to 130 frost free days