On-Farm Soil Monitoring for On-Farm Soil Monitoring for Water Resource ProtectionWater Resource Protection

Evaluating Field Practice Impact on Soil Health & Quality

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Conduct a Field Assessment First

Use the Purdue Extension publication “Field Assessment for Water Resource Protection”.

Then, Monitor the Changes Then, Monitor the Changes You MakeYou Make

Monitoring provides feedback:

•Are you making progress?

•Are the changes you made creating positive results?

Why Monitor Soils?Why Monitor Soils?

Soil quality and health has direct links with:

•Productivity

•Environmental quality.

An On-Farm Soil Monitoring An On-Farm Soil Monitoring ApproachApproach

•Farmer driven

•Easy to do

•Increases soil quality knowledge

•Evaluates impact of practices

•Leads to better decision making

Two Fundamental Approaches to Two Fundamental Approaches to Soil MonitoringSoil Monitoring

• Take measurements annually to identify trends

• Compare results with a baseline condition

Monitoring Soil Quality Monitoring Soil Quality Indicators on the FarmIndicators on the Farm

• Water Infiltration Rate• Earthworm Count• Soil Aggregate Stability• Soil Compaction Test• Plant & Residue Cover

The Monitoring KitThe Monitoring Kit

• Easy to put together• Items usually already

on hand• Kit will fit in a five

gallon bucket, plus a shovel

Preparing to MonitorPreparing to Monitor

• Obtain a copy of the publication, “On-Farm Soil Monitoring for Water Resource Protection, (WQ-43)”

Preparing to MonitorPreparing to Monitor

• Spring and Fall are best times to monitor

• Select sample sites that are representative of the entire field

OR, a problem spot you are concerned about

Preparing to MonitorPreparing to Monitor

• Make copies of the record sheet

• Fill in cropping, management, soil and weather, and field history information on the record sheet

Water Infiltration RateWater Infiltration Rate

•Infiltration rate simulates how quickly it takes soil to absorb rain water.

•Shorter infiltration times are better since less runoff from the field will occur.

Water Infiltration Rate MethodWater Infiltration Rate Method•Find a level spot.

•Carefully clear a work area by clipping any vegetation at the surface.

•Drive a 6 inch diameter ring (irrigation pipe or coffee can with both ends removed) into the soil 3 inches deep.

•Line the ring with plastic wrap

•Pour in 1 pint of water (2 cups or 463 ml), remove plastic wrap and track the amount of time it takes for this water to infiltrate.

EarthwormsEarthworms

•Earthworms improve infiltration and help aerate the soil.

•Cover crops, no-till field practices, and adding animal manure to fields all improve earthworm populations.

Earthworm CountsEarthworm Counts

Dig a 1 foot cubed hole, gently placing soil in a five gallon bucket

Search through the soil for earthworms

10 or more earthworms found per hole indicates

a healthy soil

Soil Aggregate StabilitySoil Aggregate Stability

•Aggregate stability is the ability of an aggregate to resist disruption from water.

•Soil with poor aggregate stability can result in water quality problems.

Soil Aggregate Stability MethodSoil Aggregate Stability Method3 macro-aggregates place in pint jar of water

gently swirl, observe vigorously swirl, observe

Soil Aggregate StabilitySoil Aggregate Stability

These aggregates survived vigorous swirling

A different soil dissolved after gentle swirling

Soil CompactionSoil Compaction

• Compacted soils result in less water infiltration and poorer plant root development.

• Deep-rooting plants, cover crops, and no-till cropping practices all help relieve compacted soils.

Soil Compaction MethodSoil Compaction MethodUsing a wire marking flag, or ¼” wire rod at 18” long, penetrate the soil 12” deep noting degree of resistance

and depth of any compacted layers.

Plant & Residue CoverPlant & Residue Cover

•Plant and residue cover protects the soil from adverse factors such as wind, rain, and direct sunlight

•Fields with bare spots or bare soil are at risk of erosion and runoff problems

Plant & Residue Cover MethodPlant & Residue Cover Method

•Use a tape measure at least 25 feet long.

•Imagine a rain drop hitting the surface exactly at each foot mark.

•Would the rain drop hit a live plant, plant residue, or bare soil?

•Count the number of occurrences of plant and plant residue

•Enter the percent plant cover on the record sheet

Enter the Enter the results results on the on the record record sheetsheet

Using the ResultsUsing the Results•Monitor trends and changes in soil quality in the same field over time

•Make side-by-side comparisons (within the same soil types) of different management systems

•Compare field results to an undisturbed ecosystem

•Compare problem and non-problem areas within a field

How to obtain materialsHow to obtain materials• Call toll free to

Purdue Extension

1-888-EXT-INFO and ask for WQ-43.

• Click on ‘Field Assessment’ at www.ces.purdue.edu/waterquality.

• Ask your County Extension Educator

On-Farm Soil Monitoring Helps On-Farm Soil Monitoring Helps You:You:

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•Evaluate the impact of field practices

•Increase your soil quality knowledge

•Make better decisions about field cropping practices