Farming is science, pure and simple. Agronomy is the term used; Agronomy is the science and technology of producing and using plants for food, fuel, fiber, and land reclamation. Agronomy encompasses work in the areas of plant genetics, plant physiology, meteorology, and soil science.

The science of food
The science of food

My background includes a degree from “Thee (LoL) Ohio State University” in Agricultural education. I was set to teach vocational agriculture to high school students when my wife’s father in law offered us a job on the family farm. My wife and I decided being farmers was our best option. Over the years I’ve added various continuing education credits along those lines.

New and Old School
New and Old School

When in comes to raising crops you have got to know science, and you have got to know and understand the chemistry of what your soils have going on. After you know that you can apply the “art” part. We use a blend of Old School things for nutrients like cow manure, crop rotations, and lime. We also use some of the latest technology available to us. You need both.

Robotic soil sampler
Robotic soil sampler

The Rubber-tracked Autoprobe, Left, Pulls Soil Samples On-the-go At The Rate Of 20 Cores Per Minute And Is Aimed At Large Input Dealers.

Soil sample tools
Soil sample tools

For sake of this blog post on how we take soil samples in our corn maze we will keep it simple. The tools in the picture above are similar to what I use when pulling core samples. When you pull a sample you go out to a field and remove actual samples of soil from around the field.

Soil sample farm layout

Field Sampling. Sketch your fields before sampling to reflect known differences in soils. In our case the corn maze is in one specific field but the field does have two very distinct soil types and I sample those separately just like they are two different fields.

Soil sample grid pattern
Soil sample grid pattern

Usually, it is recommended that a single soil sample should be collected for any given field or management unit. However, a single soil sample should consist of at least 25 individual cores collected from representative areas of the field or management unit, which are then mixed together into a common “composite” soil sample.

It is best to pull soil samples in the fall when soil is dry
It is best to pull soil samples in the fall when soil is dry

How much of this sample to send into the soil testing lab will depend on the analyses to be performed and the specific lab, but usually about 20-30 ounces (volume) are required.

Soil sample report
Soil sample report

Therefore, of the 25 or more soil cores which are collected from a field, management unit or problem area, only the amount needed to fill an appropriate soil sample container is actually collected from the composite sample and sent into the lab.

Soil sample bags
Soil sample bags, after you pull the sample be sure to use a plastic bucket or other non-ferrous container. For instance if you use a metal bucket you can pick up Iron from it.

Depth of sampling is usually at least six inches, but may extend to 12 inches or more, depending on the situation.

Soil sample potassium levels
Soil sample potassium levels

Sampling technique (depth and placement) may also depend on whether the field is irrigated, bedded or flat, and also on what is needed from the analysis such as nitrate-nitrogen (NO3–N), sulfate-sulfur (SO42–S), phosphate-phosphorus (PO43–P), sodium (Na) or total salt concentration, etc.. In reference to sample frequency, depth, amounts of soil needed, and tests to run; this will all depend to some extent on the nature and intent of the sampling process as to whether it involves routine management or diagnosis of problem areas in a field.

Soil sample core depth
Soil sample core depth

At the core of creating a great corn maze……..Ok, a little agronomy humor….. is getting all of this done timely and correctly. You do not want to sample soil when it is wet for instance. Doing so can affect the results you get back reflecting inaccurate Potassium levels which are a huge part of the equation. We sampled our corn maze right after harvest and are waiting on the Lab report to make fertility recommendations and applications. Based upon crop removal data we know a bit of the story already and will apply liquid manure and then balance the rest of the needs at planting time if need be.

Technology tools in the form of handheld and tractor mounted GPS systems are commonplace today.
Technology tools in the form of handheld and tractor mounted GPS systems are commonplace today.

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Tools like the GPS are used in the actual design of the corn maze and when we go into the field to cut the design paths which I will touch upon in a upcoming blog post.

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