Simple steps to determine worm populations in your field covered at MSU Agriculture Innovation Day.
There are many different parameters that can be used to determine soil health. One common measure is the number of earthworms that are found in the field. To survive, earthworms need moist soils that have sufficient residue or organic matter for food. As part of MSU Agriculture Innovation Day – Focus on Soilon Aug. 24 in Frankenmuth, MI, attendees can learn more about earthworm's role in maintaining soil health.
Earthworms perform several important functions in soil. They improve soil structure, water movement, nutrient cycling and plant growth. They are not the only indicators of healthy soil systems, but their presence is usually an indicator of a healthy system.
There are some considerations that you need to be aware of when looking for earthworms. If earthworm counts are taken when the soil is dry, the earthworm numbers may not be a good representative of the field. Earthworms may have moved deeper or to areas of the field that have more moisture. Earthworm populations will be high around areas with high organic matter. If such an area is consistent throughout the field, go ahead and test. If it is not a good representative of the field, choose another spot to test that is more uniform with field conditions. To get the best results, it is advisable to test several times during the growing season, and then take an average of the earthworm numbers.
Materials that you will need to measure worms in the field:
- Tape measure
- 2 liters of tap water
- Hand trowel or shovel
- Container to collect worms
- Solution of 2 tablespoons of mustard powder dissolved in 2 liters of water
Once you have your materials gathered you are ready to count earthworms.
Step 1: Measure a square foot in the test area and dig down 12-inches.
Step 2: Collect and count the number of worms found. If possible, differentiate worms by type. For example, label as earthworms, red worms, etc.
Step 3: (Optional) Level out the bottom of the hole, and pour the mustard solution slowly. Deep burrowing worms should come to the surface within 5 minutes. Collect and count the worms that come to the surface.
Step 4:Count and record the total number of earthworms that are collected.
Another method to count earthworm populations takes more time but is less labor intensive.
Step 1: Measure a square foot in the test area.
Step 2: Slowly pour 2.5 gallons of the mustard solution in the test area, allowing the water to infiltrate through the soil without pooling and running off. This could take several minutes depending on soil type and moisture.
Step 3: Collect and count the earthworms as they come to the surface for ten minutes after the test area is saturated with the mustard solution.
Earthworm counting is only one way to determine soil health. There are other measures that farms can use, especially with soils that are sandy and droughty, to determine the health of their soil.
To learn more about soil health, join other farmers on Aug. 24 as Michigan State University Extension hosts an educational field day focusing on soils at the Saginaw Valley Research and Extension Center near Frankenmuth, Mich. The MSU Agriculture Innovation Day: Focus on Soilsprogram is a great opportunity for farmers to learn about the cutting-edge research conducted by MSU scientists on soil health topics ranging from nutrient management and soil quality to compaction and tile technology. The event is free and open to all. It begins at 8 a.m. with registration. Nine educational sessions will be conducted throughout the day, and attendees can also view displays and demonstrations. A lunch will be provided.
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FAQs
Earthworms perform several important functions in soil. They improve soil structure, water movement, nutrient cycling and plant growth. They are not the only indicators of healthy soil systems, but their presence is usually an indicator of a healthy system.
What is an indicator of healthy soil? ›
Soil productivity, usually measured in terms of crop yield, is influenced by the cumulative effects of many soil health indicators. Visual indicators include exposure of the subsoil, change in soil color, gullies, ponding, runoff, plant response, blowing soil and deposition.
Are earthworms an indicator species? ›
Low or absent earthworm populations are an indicator of little or no organic residues in the soil and/or high soil temperature and low soil moisture that are stressful not only to earthworms, but also for sustainable crop production. Earthworms stimulate organic matter decomposition.
What is the earthworm test for soil? ›
The Worm Count is an actual field test used by farmers across the country and a recommended practice by the Natural Resources Conservation Service (NRCS). The number of worms in your soil directly indicates the amount of organic matter currently in your soil.
How to tell if soil is healthy? ›
5 Signs of Healthy Soil in Honor of World Soil Day
- You can't see healthy soil. ...
- Healthy soil has living roots growing in it. ...
- Healthy soil is teeming with life. ...
- Healthy soil produces high yielding crops, even when the weather doesn't cooperate. ...
- Healthy soil is surrounded by healthy water, ecosystems, and people.
Earthworms are probably the best healthy soil amendment you can introduce to a garden. They improve garden soil not only through soil aeration and loosening but also because they increase nitrogen levels in the soil. So, composting worms is a no-brainer!
What are the three major indicators of soil quality? ›
There are three main categories of soil indicators: chemical, physical and biological. Typical soil tests only look at chemical indicators. Soil quality attempts to integrate all three types of indicators. The categories do not neatly align with the various soil functions, so integration is necessary.
Which is considered the single best indicator of soil health? ›
One of the best indicators of soil health is soil organic matter content. Soil organic matter, measured as total soil carbon, represents the amount of carbon compounds in the soil that are derived from living and dead organisms and plant tissues.
What indicator is used for soil? ›
Organic matter and biological indicators include: total organic carbon (C) and nitrogen (N), mineralizable nitrogen (as a surrogate for microbial biomass) measures of labile or soluble carbon and nitrogen (such as hot-water extractable C and N).
What are the disadvantages of earthworms in soil? ›
Earthworms can also cause problems in the garden. Their burrowing can damage plant roots and make it difficult for plants to grow. This can cause harm to the plant's ability to take up water and nutrients from the soil and can ultimately lead to plant death. Hungry earthworms can stunt new plant growth.
Dennis Linden tells one way to find worms: First, look at the soil surface. Castings ("worm poop") are small piles or pellets of soil, often mixed with some plant litter. Castings are signs that earthworms are present.
Are earthworms bioindicators? ›
Earthworms are often suggested as bioindicators of soil quality because they are an important part of the soil system and also because they are frequent, easy to collect, and rather simple to identify (Buckerfield et al.
Are earthworms healthy for soil? ›
Earthworms are an important part of maintaining healthy soil. Think earthworms are only good for fish bait? Think again! Earthworms play a valuable role in soil health and viability in forests, prairies, gardens and even on farmland.
How many worms should be in healthy soil? ›
25 earthworms per square foot of soil equal 1 million earthworms per acre. Studies in England have shown that in healthy soil forty tons of castings per acre pass through earthworms bodies daily. A new USA study indicates 12 million worms per acre which move 20 tons of earth each year.
Which soil is best for earthworms to live in? ›
Silty soils with high water holding capacity and organic matter provide ideal habitat for earthworms compared to sandy soils, which have lower organic matter content and water holding capacity, and dry and reach uncomfortable temperatures quickly.
Is it good to have worms in your plant soil? ›
Studies of earthworms in agricultural settings have found that earthworm burrows can improve water infiltration and soil aeration, and their castings (excrement) form soil aggregates by combining minerals and organic matter. Earthworm activity can also relieve compaction and make nutrients available to plants.
How do you know if earthworms are healthy? ›
SIGNS OF A HEALTHY WORM BIN □ Bin smells earthy like the soil. Bedding and food scraps are disappearing over time. Worm castings are accumulating. Worms have glistening skin.
How to tell if topsoil is good? ›
Generally speaking, lean toward darker shades – anything from coffee-colored to almost-black. Rich, dark tones indicate a high level of organic matter, and the more organic material present, the greater the concentration of nutrients.
