How to conduct an in-field soil health assessment

Healthy soil (left) vs compacted soil (right)

By: Bailey Tangen and Gabi Bolwerk, Extension educators

Fall is a great time to start thinking about how to adjust your management practices to reduce erosion and improve soil health. A good first step is to understand the current state of your soil. To do this, you can perform a quick in-field soil health assessment. In this visual guide, we’ll walk you through how to conduct your own in-field soil health assessment.

In an in-field soil health assessment, we look at the biological and physical properties of soil as they relate to soil function. This assessment can be done in 15-20 minutes and should be done in a few spots in your fields to get a full picture of how your soil functions. To learn more and to get help doing an assessment, call your local NRCS or SWCD office. These folks are willing to come out to your field, do an assessment, and provide management recommendations to protect the vitality of your operation and the productivity of your soil.

A few notes before “digging in” to in-field soil health assessments:

After harvest is a great time to do a soil health assessment.
The only tools you’ll need are a shovel and your observational skills.
Keep in mind the context of your land. For example, sandy soils won’t look or behave the same as clay soils. It can be helpful to compare soil within your field with a less disturbed soil (fence row, tree line) so that you have a reference of what your soil health capacity looks like.

What to look for

Surface cover: Surface cover includes the living and dead plant material on the soil surface. Healthy soils have at least 75% soil cover, whereas less healthy soil has less than 30% soil cover. Soil cover keeps soil in place, and the nutrients in the plant tissue returns back to the soil food web. Having a variety of plant residues through crop rotation, diverse pasture species, and cover crop species provides different types of food to the beneficial organisms in your soil.

Crusting: Soil crusts form when surface soil structure breaks down due to rainfall and excessive tillage. Healthy soil maintains open and porous surfaces, allowing for good water infiltration and seedling emergence. Less healthy soil has a crust on the surface, which seals off the pores, inhibiting seedling emergence and reducing water infiltration.

Soil structure: Dig a small hole and look for aggregates, which are clumps of soil that make up the overall soil structure. Healthy soils have a crumb-like structure and can break apart easily, leaving no large clods. Less healthy soil may be hard and form large clods, break along horizontal planes, or have little to no aggregation at all. Less healthy soil structure can restrict root growth and water infiltration.

Compaction: Healthy soil should be relatively loose, allow for unrestricted root growth, and be easy to dig in when not dry. Soil that is less healthy will have hard layers that are difficult to dig through and may severely restrict root growth. Compaction can occur at the soil surface or at deeper depths, such as the depth of tillage. Heavy machinery on wet soil can create deep compaction.

Roots: In healthy soil, there should be uninhibited root growth with lots of fine roots. In less healthy soil, roots are restricted, leading to fewer fine roots and horizontal root growth above a compacted layer. Because living roots release sugars and compounds that feed microorganisms, the area around roots becomes a hotspot of biological activity. To improve soil health, there should be living roots in the ground whenever possible. This can be achieved through cover crops, perennials, or a winter cash crop.

J-rooting due to compaction

Biology: A healthy soil should have lots of earthworms (at least 3 per shovelful) and many casts and earthworm channels. In a less healthy soil, there are little to no signs of earthworms or earthworm activity. Earthworms are some of the most well-known ecosystem engineers in our operations. But earthworms aren’t the only type of soil biology we want to see. You should see at least three different types of beneficial soil organisms (not pests) in a healthy soil, which can indicate a healthy food web.

Infiltration and ponding: Healthy soils have good infiltration, meaning they absorb water quickly. There is very little ponding after a heavy rain, and very little runoff and erosion. In a less healthy soil, water absorbs very slowly. There is ponding after moderate rains, and lots of runoff and erosion. Soils with lots of pores, especially large and medium pores, are better able to take in rainfall and have more plant-available water for crops (Tangen et. al 2025).

What to do next after assessing your soils?

After you’ve completed your in-field soil health assessment, take time to reflect on what you’ve observed. Record your notes and photos from each assessment location - these will be valuable references when you evaluate changes in future years or after implementing new management practices.

Start by identifying your top soil health concerns. Is erosion your main issue? Are you noticing compaction, poor infiltration, or limited biological activity? Prioritize one or two goals to focus on each season rather than trying to fix everything at once.

Here are a few practical next steps to consider:

Address erosion first. Maintain at least 75% surface cover to protect your soil from rainfall impact and wind. Reduce tillage intensity, leaving crop residue, and consider integrating cover crops or perennial vegetation to keep roots in the ground.
Tackle compaction. Avoid tillage when soils are wet, limit traffic where possible, and use living roots - through cover crops or extended rotations - to naturally alleviate compaction over time.
Improve soil structure and biology. Feed your soil organisms by maintaining diverse crop rotations and cover crop species. Remember, soil biology builds structure, which in turn improves infiltration and water holding capacity.
Build organic matter. Practices that reduce disturbance and keep living roots in the ground - no-till, strip-till, cover crops, residue retention - help increase organic matter, which supports every aspect of soil function.

If you’re unsure where to start or want a second opinion, reach out to your local NRCS or SWCD office. They can help you assess your soil health, connect you with cost-share programs, and design management plans tailored to your operation.

Healthy soils take time to build, but small, consistent changes can lead to lasting improvements in productivity, water management, and resilience. By assessing, observing, and adapting each year, you’ll be setting your soil - and your farm - up for long-term success.

For more information on management strategies to increase the health of your soil, check out these extension resources:

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