Posts Tagged ‘topsoil’

Losing Topsoil

The other day, I was on a bodybuilding site reading through a comment battle between vegetarians and vegans versus the meat eaters. Yes, this is a form of entertainment for me. One of the commenters pointed out that veganism isn’t the solution since we may well run out of topsoil in 60 years.

WHAT?

Running out of oil makes sense. So does running out of potable water. But soil? Ok, so I guess I knew that it was being degraded, but it’s really scary to think that I might live long enough to see the end of enough topsoil to support agriculture. With only a moment of research, Time magazine supported that assertion for me. The article goes on to point out that what is missing from the soil will be missing from the plants grown in the soil. So even before the soil is considered to be unusable, it’s already being less useful to those of us depending on it. Another point the article makes is that degraded soil doesn’t hold water. The worse the soil is, the less effective irrigation is.

First- why are we destroying our soil? The short answer is, we are taking and not giving. When we do give, it may well be poisoned. On most conventional farms, they’re simply too big to do things like till in nicely decomposed manure in the spring, or spread fresh manure after harvest in the fall. Spring in Lancaster County, Pennsylvania was invariably announced with the smell of manure. The Amish farms would start their field prep by spreading the manure from their cows on their farm fields. Given a choice, Amish fruits and vegetables were the way to go when we were growing up, when we didn’t get enough out of our own garden. However big the Amish farm is, though, it is just a drop in the bucket compared to the operations that supply grocery stores. A family-sized herd of cows won’t give nearly enough manure to replace the organic material carted away to ship to the store. Their animal counterpart, CAFOs, can’t really be used, either, since the waste they produce is pretty much toxic. In short, we are pulling out organic material, vitamins, and minerals, and all we put back is “NPK.” Because, given no other choice, plants can more or less be grown on primarily nitrogen, phosphorus  and potassium. While organics are a step up from conventional produce, if you’re buying them from a big company, they’re probably still guilty of taking without giving. They just leave less poison behind.

Second- how does this affect me? When it comes down to it, I admit that what gets me moving the fastest on an issue is if I know it will have a major impact on me. This will. Already, conventionally grown vegetables (and the meat that is grown on conventionally-raised grains) offers me less vitamins and minerals than it could. Than I need. As the population grows (seriously, enough already, people) and the arable land shrinks, food prices will go up. Which means I will be paying more money for an increasingly inferior product. The more soil we lose, the more potable water we lose, since degraded soil just can’t hold on to it. I think everyone can recognize how bad that is.

So now what? I don’t own a farm that I can convert to something more sustainable. (If you do own a farm, though, that is something to keep in mind.) I do have a back yard, though. Along with the garden, I can build soil in the rest of the yard by creating a place where native plants and grasses can grow and do their thing. Going native generally means fewer chemicals (if any) and once it is established, way less upkeep. Having a healthy lawn also means that when I’ve had it with food prices, it’s much easier to convert to a healthy garden. I will already be working on the topsoil, including encouraging the growth of all the creepy-crawlies that keep a garden healthy. I can also make a more concerted effort to support those that support our soil. Buy local, buy organic, and buy from small producers. 100 acres is much easier to take good care of than 1,000. 10 acres they should know even more intimately. Buy grass-finished meat. Not only is it better for you, but it is a lot better for the environment. If you live in an apartment, ask a friend if you can help in their garden, or hijack a corner of their lawn to start your own. There aren’t many that would turn down help with pulling weeds or free, fresh veggies.

Will any or all of this fix the mess we’ve made of our farmland? Not hardly. But the less we rely on conventional farming, the less affected we will be when it collapses. The more we support responsible and sustainable farming, the more it will be seen as a viable option for those conventional farmers that just can’t do it any more. I doubt there is a single farmer out there that actually wants to destroy their fields. It behooves us to make conventional farming less profitable than sustainable farming. Help the farmers help the soil. We can’t live without it.

Class: Understanding Front Range Soils

“Soil is precious and we treat it like dirt.”

This class was taught by Jean Reeder, Ph.D. soil scientist. She spent 30 years with the USDA ARS, the agricultural research service. Since retirement, she is now a consultant for the CSU Soil Testing Lab and she is one of the instructors for the Colorado Master Gardener program. She has also discovered that she didn’t really understand the soil in her own back yard. Of natural, agricultural, and urban soils, urban soils are the most complex and the least understood. She has begun applying her skills to changing that.

Anyone who lives in Colorado knows that we face a lot of challenges. Our semi-arid climate is cool with a short growing season, dry, and highly variable in both temperature and precipitation. However, more than 80% of plant problems are because of the soil. It is the fundamental component of the landscape. That makes it the biggest challenge. However, it is also the least understood. We have even less information to go on than most of the country, as our soil is as different as our weather. Where most soil is more acid, ours is alkaline. If you find a native soil around here that is 2% organic matter, you’re doing really well. In Iowa, 6-7% organic matter is perfectly normal. We also have free lime. She told us about one woman she knew that preferred to send her soil samples to a lab in Missouri to be tested. They never tested for free lime, since it isn’t an issue in Missouri.

There were a few main points I got from this class. The first is, test your soil. The old saying is “feed and nurture the soil and the soil will feed an nurture the plants.” That’s true, but how do you know how to nurture it if you don’t know where it is now? Sending off samples for testing is a bit more expensive than picking up a soil test kit at the store. However, you get a lot more information and a lot more accuracy. The other thing is to get it tested locally. I use the CSU service. Granted, the lab is in Fort Collins, which is not exactly around the corner from Colorado Springs, but they know Colorado. They know about free lime and our increasing problem with salt in our soils. They can tell me how to manage it in a way that will work here. The kits you can pick up at the store are apparently usually calibrated for acidic soils, which makes them worse than useless in our alkaline soils. They also don’t come with instructions for fixing any issues you have.

Once you get your test results back, there are a couple of things that it is best to just make peace with. The pH and the texture are almost impossible to change, and any changes may have other consequences. Our soils tend to be more clayey. One apparent solution is to add sand. Aside from the fact that you have to add too much sand for that to be practical, the recipe for concrete is lime and sand. It’s not a guarantee, but if you’re unlucky, you might end up with a concrete slab where you had intended to put in a garden. As for pH, our soils are very well buffered, so they resist being changed. One possible change is to add sulfur. However, if you have a high-calcium soil (lime is usually calcium carbonate), you end up making gypsum. Gypsum is used in places as a fertilizer. However, it is a salt, so you will be increasing the salt content of your soil. The only way to change the pH with any hope of permanence is to manage the garden correctly and consistently for about 50 or 100 years or move to the mountains. There are some old gardens and gardens in the mountains that are slightly acidic. However, those are the exception not the rule.

The result of squished roots and a rough spring.

Now that you have made peace with your texture and pH, it’s time to talk about amendments. All amendments are not created equal. In fact, all compost is not created equal. We do not have naturally saline soils. However, the application of high-salt fertilizers, both organic and not, is turning salt into a problem. There’s a reason people used to salt the fields of their enemies. You can’t grow anything in salted soil and, unless you have massive amounts of high-quality water to flush the salts through the soil layers, it is almost impossible to fix. She did a study of bagged, commercial fertilizer. However, it never got published because the only consistency was that animal-based ones had very high salt content and plant-based ones tended to have merely high salt content. Other than that, there was no telling what would come out of a particular bag. Even if you go natural, there is still a huge variation in what you can get. She showed us numbers of actual fertilizers she had analyzed from non-bagged sources. The numbers were all over the place. Including two that ended up with toxic amounts of trace minerals and several that were going to cause salt issues if they were used with any regularity. If you are considering using your neighbor’s horse manure, she mentioned that what they are fed affects the quality of the manure. The quality of what goes in affects the quality of what comes out the other end. Think about that for a minute. I sure did.

This one isn’t too happy with it’s placement either.

The last major point is compaction. I have run across this as being a problem in gardens before, but she took it to another level. Compacted soil means that the aggregates in the soil, the structure made from the mineral content and the organic material, have been destroyed, which means that there are few if any pores in the soil for air and water to penetrate. If you live in an urban area, it’s best to assume that your soil is compacted. If you are able to do so, you will want to fix that before you put down lawn and gardens, as it is almost impossible to fix later. If your soil has no, or few, pores with air and water, roots will not have anywhere to go, or a reason to go there. The smaller and more restricted a root system is, the smaller the above-ground part of the plant will be. I have notice small trees in “hell strips” between the sidewalk and the road recently that are only leafing out on their lower branches. This is apparently a result of restricted root growth combined with a dry spring. The upper branches had to be sacrificed because the limited roots couldn’t support them in the rough conditions we have had this spring. If it wasn’t trapped between the compaction under the road and the compaction under the sidewalk, the roots would be able to spread out, giving them half a chance to support the growth that had gone on before conditions got bad. When you walk across wet, loose ground once, you just compacted that ground by 75%. If you walk across it four times, now it’s 90% compacted. Now think about the damage a bulldozer or crane will do while the house is being constructed.

The overarching concept from this class is that, with two exceptions, less is more. On average, it takes about 150 years to build an inch of topsoil in nature. Colorado would need more time than average. Therefore, taking 10 years to slowly build a to-die-for garden is still well above average. The fewer amendments you use, the less likely you are to make a mistake. If you salt your garden or add toxic levels of a nutrient, you will be spending a lot of time and money to fix it. Along the same lines, once our native soil has been disrupted, she let me know that it is very hard, very expensive, and often heartbreaking to restore it. The less of the native landscape we disrupt, the less we will have to painstakingly restore. Tilling and other machines tend to break up soil aggregates, affecting the soil structure. Hand-digging is far less likely to do so. What we need more of is patience and knowledge, hence the slightly lengthy post. Your soil is unique. The more information you can gather, and the more time you can spend with it, the better equipped you will be to know how to nurture it.