How to do a soil test?

[ksl1]

I have never done a soil test. How deep do you dig? Can you take a couple samples from different areas of a field and mix them for one test? I would appreciate any guidance.

 

[grannysoo]

You can probably get your local county extension agent to come and pull the soil tests for you. Will probably cost a small fee.

In our area, Southern States (formerly Gold Kist) will also do them for you. Paid $12.00 per sample this spring. Well worth the money!

 

[SRBeef]

I have never done a soil test. How deep do you dig? Can you take a couple samples from different areas of a field and mix them for one test? I would appreciate any guidance.

First of all decide how many different fields/areas that you want test feedback from. Sample fields that have obvious different topography, crop history, soil type/slope/aspect separately. In other words the six slices into each jar will be from similar looking areas in one field to yield one composite sample for that field or area.

Once you have decided how many fields/areas you want to sample, take maybe six samples from each area, mix them together in a clean preferably glass container (big glass jar works well).

Generally you want to sample a vertical slice from the surface to about 6" deep. This is where most of the nutrient feeder roots are. There are hollow tubes to do this. However what I do is to really clean the blade of a square bottom garden spade. I sharpen mine with a file or grinder to make it cut cleaner. A stainless spade works best but are rare. Dig a hole or take a chunk of soil or sod out leaving one side with a clean vertical surface. With the spade I then take another vertical slice out of this clean face about 2" thick by the width of the spade blade. I then take a clean sharp knife blade and make 2 vertical knife cuts on the slice on the spade blade leaving about a 2" x 2" x 6" tall vertical column of representative soil in the center of the spade blade. take/cut leaves off of the top surface but leave everything else. Carefully put this undisturbed vertical column in the jar.

Do this in about 6 places in each like area and you will have 1 jar with soil representative of the particular field or area you want sampled. I put some saran wrap over the jar before putting the lid back on to keep the lid metal from affecting the sample. Repeat this for each different field or area. It is important to take more than one core in each area to get a representative test for the field. 6 is a good number but you can do more or less depending on how accurate you want each test result to be.

A regular soil sampling tube is a lot faster but the above method is what I use. The key is to choose good spots to sample and then take samples without contaminating the vertical 2 x 2 x 6 core slice.

Some folks use zip lock freezer bags rather than jars. Check with the lab you will be using to see what containers they recommend. Remember to clearly label each jar or bag with the field ID.

A key point here, especially with livestock, is to avoid sampling an area with recent manure directly on it. I hope this helps. Good luck.

 

[Jogeephus]

Here is what our extension recommends.

Take 10 -20 samples in each field (more the better)

For row crops - sample to plow depth
For lawns, turf and pasture go 4"
Gardens - 6"
orchards - 8-12 inches
pecan groves 6 - 8 inches

Each sample should represent no more than 15 acres. Avoid sampling in the low or high spots and along roads, fences, fertilizer bands etc. If you have a week spot in the field, sample it seperately.

Put soil in a clean plastic bucket and mix well and put in sampling bag.

 

[ArrowHBrand]

The cooperative that well use to apply our fertilizer will come out and do it for free. It all depends if you have the time to spend to take your own samples and feel confident enough to do it also.

 

[dun]

Some one posted a method using a drill to gather the samples. Hopefully they will chime in with how it's done.

 

[novatech]

Some one posted a method using a drill to gather the samples. Hopefully they will chime in with how it's done.

Start with a very long extension cord. and in you area I would use a hammer drill. :lol2:
OK we got past my smart A. An electricians auger bit will work. Just about any size will work above 3/4 inch. Just drill to the depth desired and put the dirt removed in a bucket mixed with the other samples from the same pasture. A 1/2 inch drill will probably be necessary. You will have to resharpen the bit if you ever plan to use it again for it's intended purpose.
Just wanted to add; One of those old brace and bit drills would probably work just fine.

 

[dun]

Some one posted a method using a drill to gather the samples. Hopefully they will chime in with how it's done.

Start with a very long extension cord. and in you area I would use a hammer drill. :lol2:
OK we got past my smart A. An electricians auger bit will work. Just about any size will work above 3/4 inch. Just drill to the depth desired and put the dirt removed in a bucket mixed with the other samples from the same pasture. A 1/2 inch drill will probably be necessary. You will have to resharpen the bit if you ever plan to use it again for it's intended purpose.

That's how I do it but there was something about drilling through the bottom of a plastic cup to catch the dirt.

 

[novatech]

Good idea. I have done the same thing drilling a hole in a sheetrock ceiling. Drill a hole through the cup and leave it on the bit. Next drill the hole and the cup catches all the dust. I don't see why it would not work drilling down into the dirt.

 

[dun]

Found the thread:
viewtopic.php?f=14&t=35472

 

[cfpinz]

There are usually some soil probes for sale on ebay, I bought a used one last year for about 20 bucks.

 

[EAT BEEF]

I gave five bucks for real nice one at a farm sale,I coudn't belive how many people came up and asked me what is that thing. :???: