I am about to inherit a good chunk of land in western Colorado. I have been cautioned to get soils tests completed before accepting the title, but because of the amount of land, I’ll need to do dozens of samples and that adds up to pretty good money.
Anyhow, I have a background in chemistry and am familiar with a few testing procedures. I’d like to perform these tests myself. All I need to be concerned with are the following: pH, N, P, K, salts and (but not necessarily exclusive to) Fe and Cu, plus the % of organic matter in the soil.
I’d much rather spend the money improving my personal lab equipment than pay a professional testing lab. Can anyone help?
Are porewater tests acceptable for the pH, N, P, and K? That’d be easiest. % organic matter is a piece of cake as long as you have a good kiln/oven - but you wouldn’t really want to buy one for just a few dozen samples.
What are you testing for? Being cautioned about performing the tests makes me think you’re worried about some potential contamination issue - unreported wastes dumped and the like, but aside from the tests for Fe and Cu, this battery of tests won’t help you much in that regard. You’ll really need to know something about the type of contamination to expect. Or are you planning on farming this land?
The basic soils test kits sold by LaMotte, Hach and others will get you pH, N, P, and K. You could then get individual Fe and Cu kits. It would be good to know why just those metals are a concern to you, and what quality of data you are looking for. I personally use this kit with my students, and it is pretty good, but it is probably overkill for your needs.
I agree with wevets here – I can’t think of a reason to worry about soil testing before accepting title to an inherited property unless there was some concern about potential contamination. And if so, sampling without knowing where to collect the samples and what to test for would be completely meaningless.
Is there some unusual history to this property that should be looked into?
Your list of constituents to test for seems like a check list to see if it’s viable farm land – good to know if you’re buying a farm, but would you reject the inheritance just because it’s not good farm land, if that turned out to be the case?
Some good questions have already been asked and accurate statements made. So as not to be redundant, I’ll only provide information.
Soil tests are normally performed so a farmer will know how much and what type of fertilizer to apply. If you’re not getting into the row-crop business, I don’t know why you’d need a soil test.
Check with your county extension office. Normally, they will provide boxes for you to put soil samples in, and mail the boxes to the state laboratory, where the tests will be done for a nominal fee. The last soil tests I had done cost $3.00 each, so there’s no need to purchase your own expensive lab equipment.
If the testing you were advised to do is because of some unusual toxic situation that is known to exist there, checking for N, P, K and pH will hardly answer that type of question.
Also, it doesn’t sound like you have much experience in this area. Your (and my) taxes help pay for the university extension system, which makes farm agents available to provide on-site advice to landowners free of charge. I recommend you schedule a farm visit with the extension agent in the county where your property is located.
Here’s a tip: If I learned that I was going to inherit a large tract of land, soil tests would be way, way down my list of things to think about.
Because this is my area of expertise (I’m an environmental engineer), I’ll join the bandwagon.
The only reason I can surmise that anyone would be cautioning you to conduct testing prior to accepting title to a property would be if there is a possibility of environmental contamination on the site.
If you suspect this may be the case, you may wish to obtain legal advice prior to accepting the title. I do not know Colorado environmental law, but in many jurisdictions, the current owner of a contaminated property can be held legally liable for any cleanup actions required under applicable environmental laws.
You may also wish to hire an environmental consultant to conduct an environmental site assessment (ESA) of the property. ESAs are conducted in phases, beginning with background research (a Phase I ESA), and followed by soil and groundwater testing if indicated (a Phase II ESA).
By the way, the type of testing required for an ESA is not something you would be able to do yourself, unless you have some very expensive lab equipment available, including an inductively coupled plasma atomic emission spectrometer (ICP-AES) for metals testing, a gas chromatograph/mass spectrometer (GC-MS) for organics, etc.
Wow! These are all great suggestions, thank you for your consideration. First, I’m sorry if there’s a huge gap in between my posts. I only have access to a PC during my lunch, about noon Colorado time, so please forgive me if I don’t reply individually. Also, I think I should clarify about the test.
The main reason for the concern is because this area of the country is entirely encased in what’s called Mancos shale which leads to lethally salty soil. Plus, the levels of N, P and K are often so high that any amendments could end up doing me in in the long run. I planned to grow soy and alfalfa on the land in order to make it pay fairly soon. If the land is not so good for crops I can refuse the title and it will pass over to my uncle who’ll probably leave it fallow or rotate his stock to it.
The problem is, the local CSU extension says I have to hire a soil test, which runs about $35 per sample. I’ll need about 10-12 samples per acre, which adds up to a lot of money over 10 acres. I’d much rather buy a bunch of burettes, flasks and solutions to totally nerdify my lab.
(Maybe I’m asking for a lot of info or even trade secrets since there are so many discrete tests I will need to perform.)
The various methods are not really a secret, you can find laboratory manuals and books of methods for soil testing at any large university library or online from Hach, LaMotte, etc. These companies post detailed instructions on how to use their kits in pdf format for free download.
These companies make money through convenience, supplying all the necessary glassware and pre-measured reagents in tablets, droppers or foil “powder pillows”. Depending on the test, some of these special reagents are designed to combine two steps of the traditional lab method, or precipitate out a potentially interfering substance.
The problem I see in what you’re proposing is that you’ll potentially have to buy a lot of reagents, which might add up to more than a simple kit. Of course, if you already have a good supply of lab equipment and reagents, this might not be such a concern.
If you have a portable spectrophotometer and a source of standards, you can really geek out and get much better accuracy with the colorimetric procedures by establishing your own concentration curve rather than using the simple color comparator that comes with the kit.
I can’t help but believe there’s something you’re not understanding abut the process. 10 samples per acre @$35 per sample =$350 per acre for soil testing. That’s simply not within the bounds of reason. No farmer would ever get a soil test if they cost that much!
Here, if I wanted to get a soil test on a ten-acre field, I’d proceed as follows:
Get about one trowel full of soil from 10 representative spots in the field, mix thoroughly in a bucket, and send one pint of the mixed soil for a soil test. Thus, one soil test for ten acres. Even at $35 per test, it’s only costing you $3.50 per acre, or $35 for a ten-acre field.
I strongly suggest that you look into this in more detail before you either spend big bucks for soil testing or “give away” land that you’ve inherited.
Worst case scenario, if your uncle can let it lay idle, why can’t you?
John Carter makes a good, if a bit oversimplified, point. If you do a good job evenly distributing samples randomly among independent plots or along known gradients, and then mix them together (in the business it is known as compositing samples), you may be able to to significantly reduce the number of samples necessary to estimate soil conditions throughought the entire parcel of land.
Thanks for the technical information upthread, Stan. I don’t think compositing is an option because of the variability in the local concentrations of salts. I’d hate to lay in some beans and lose 1/3 of my crop due to extreme alkalinity.
So basically what you said in your earlier post is that I need to isolate the nutrients I’m testing for, precipitate out the junk and test accordingly. It seems the NPK (and Fe) will be pretty easy. As for organic comp testing, do you know how that’s achieved? Also, should I consider buying a pocket-sized salts meter?
In many soils, the percent organic matter can be estimated very easily by soil color and texture. I have no idea whether this would be an option (or accurate enough for your needs) based on what you have already said about the unique soil characteristics in the area.
As mentioned by Wevets, above, percent organic matter testing can be accomplished by burning off all the carbon to CO2, usually in a muffled furnace, but a kiln can be used. First the sample is dried to constant mass at a low temp ~ 105C, then it is ignited for a prescribed interval, such as 1 hr at 500C. The sample is then re-wetted and dried again. the difference in mass between the initial dry sample and the ignited sample is the percent organic matter. You must re-wet the sample because clays will lose water of hydration at 500C but not at 100C.
I don’t have any advice for you about salts meters, aside from the fact that if you already have a standard BNC pH/ORP meter or other 4-20mA meter, I would WAG that you might be able to get by by buying the ion-specific probe rather than the whole meter if you have a decent set of calibration standards. Then again I have no idea what we’re talking about here in terms of cost- I just have cobbled together some frankenstein lab/sensor equipment in this mattter.
One thing I did not mention in my earlier post was to check the existing soils maps put out by the NRCS or USDA for the area. My experience here is limited to the northeast US, so I have no idea to what degree the soils in this area may have been mapped, when, or if the info would be useful to you.
Thanks again, Stan. I got the salts bit sorted out through the CSU extension office. They test salts concentrations for free. It looks like I’ll be on the right track.
There appear to be no books in my local library about soils tests. Does anyone know of any good books I might be able to order online? Also, how many years of school does it take for me to learn enough to open my own soil lab, or are accreditations necessary? The lab the extension recommended is in Nebraska, I think.