Soil Sampling

Holst Precision Ag offers a couple different options when it comes to soil sampling.

Grid Sampling:

Want to know more about your field? Let us help. Holst Precision Ag is now offering the ability to test your field. We will send one of employees out to your field, pick up a samples, and ship them off to be tested. Within a few days you will know all there is to know about your field.

To obtain these samples an employee will drive a boundry around your field using a UTV. Then they will set "grab points" using the Ag Leader SMS Mobile Software. Depending on the size of the field will determine how many points will will be set up for pick up. These points are set at intervals of 2.5 acres. When the grab points are taken it will create a map of the field.

Zone Sampling:

Site Specific Fertility Management

Need to get more indepth? We have another option for you. Holst Precision Ag offers the ability to sample your fields through zone mapping.

How is this done?

Define a spatial management unit
1. Size - a scale that takes into account variability of field, yet not small enough not to complicate decision making processes.
2. Must be economical
Landscape Characteristics affect how well an area can produce
1. Elevation
2. Soil Type
3. Drainage
4. Slope
Defining a zone
1. Yield Maps
2. Aerial Imagery
3. Soil Type Maps
4. Elevation Maps
5. False Color Vegetation Map
Creates a field into zones usually around 4-12 zones (average of 10) that a generally similar in size.

Certain attributes are tied to each zone. The come into two different categories. These two attributes are yield and soil test data. Yield Data contains both single year and multi-year averages for each fie Soil is tested for multiple characteristics: PH, Organic Matter, Phosporus, Potassium, Soil-Cation Exchange Capacity, Buffer PH, Calcuim, and Magnesium.

PDF Version

Example Zone Map

False Color Zone Map

Elevation Zone Map

Yield Zone Map

P Level by Zone

Cores are pulled at Random within each zone.
Test sites are 1 acre apart
Each Zone is sent to a lab as one sample
Soil Test is the tied to zone layer.

Soil Sampling Example

K Level by Zone

Advantages of Zones

Make decisions easier

Allows you to isolate where top producing areas are as well as lowest producing areas.
Takes into account landscape characteristics and production level before other variables such as soil test level.
Streamlines VRT process
Easier to make judgment calls when it comes to budgeting
- Example: Corn is at $3.50 do I need to spend as much on fertilizer in zone 1 vs. zone 2? Zone 1 yields the lowest.
- Example: I have budgeted 34,000 seeds an acre but I know zone 3 always produces, What if I planted 36,500 there, because I know it can handle it, and only 32,000 in zones 5 and 7 that are poorer soil and along the timber edge.

Streamlines VRT Process

Vector layers- Easy to apply equations too.
- Removal plus build
- Removal with 0 rate cutoff for high testing areas
Easy to adjust according to a budget
- I've budgeted $x an acre for DAP and Potash lets apply at levels to meet our budget, but take into consideration yield history and test level
Easier to make your own VRT if using mapping software

Farm Research

Now that we have isolated the zone it is much easier to get results from trying a new practice or rate.

Seeding with Check Block Tests

Seeding Rate and Test Strips

Guidance Lines Map

created with RTK boundaries
- used to segment out specific passes through the whole field to have a different seeding rate

Future Development

Profit/Loss
- Once zones are set now we can easily start to build a cost and breakeven layer by zone
- Possible layers
  - Breakeven bushels at current input costs and commodity price
  - Profit loss off current year inputs and yield

Holst Precision Ag