Maintaining soil fertility is a never-ending challenge for farmers, who are tasked with feeding a growing population using the same (or even less) land mass every year – and crop rotation is just one strategy farmers can deploy to keep their lands fertile.

For decades, it was thought that artificial fertilizers were an easy solution to soil degradation – after all, what could be simpler than just applying a man-made product to replace what nature lacks?  

But as we’ve learned more about more about soil, it’s become clear that artificial fertilizers aren’t a cure-all for nutrient depletion, and that their overuse can actually have a negative effect on soil quality as well as the wider environment.

Crop rotation is a natural method of soil enrichment that works with the soil ecosystem to preserve structure, encourage biodiversity and fix nitrogen and other nutrients.  Let’s take a look and how and why farmers do it.

What is crop rotation?

Crop rotation is a farming practice that involves systematically changing the type of crop that is grown in a particular field or location, usually from one year to the next – so instead of planting say, corn, in the same field year after year, the farmer rotates his crop by planting a different crop or group of plants in a specific sequence.  The types of crops in a rotation will depend on climate, soil type and the farmer’s goals.

Why do farmers rotate their crops?

In almost every aspect of the living world, variety is a good thing.  The more diversity that exists in any ecosystem, the healthier it will be – and soil is no different.  By rotating their crops, farmers can change up the variables when it comes to their soil ecosystem – factors like root depth, the volume of organic matter, moisture uptake and even the presence of insects can all have beneficial effects for the soil, and therefore subsequent crop yields.

Key benefits of crop rotation

Let’s take a look at some of the benefits of crop rotation as opposed to monocropping (growing the same crop in the same place every year).

1. Soil health improvement

Crop rotation is primarily used as a method of enriching the soil by rotating crops that deplete nutrients with crop that add nutrients – particularly nitrogen.  Leguminous crops like clover, vetch and peas are known as ‘nitrogen fixing’ plants, which means they capture nitrogen from the air and sequester it in the soil via their roots.  As well as being cheaper and more environmentally friendly than using man-made nitrogen fertilizers, it’s thought that using nature in this way makes nitrogen in the soil more readily available to subsequent crop cycles.

2. Erosion prevention

Certain crops in a rotation can be used to minimize soil erosion.  Plants like grasses have deep roots and underground rhizomes that bind the soil together, reducing the risk of topsoil being washed away by rain or carried away by high winds.  Plants with deep, penetrating roots also help prevent soil from becoming compacted, which allows moisture to travel deeper and encourages the presence of earthworms and other organisms that work to break down organic matter and enhance the soil’s structure.

3. Weed management

Crop rotations that include cover crops can aid with weed management by physically suppressing weed growth – stopping weed seeds from getting the moisture or light they need to germinate.  But changing up your crops – and therefore the wider conditions in the field – can also stop any one weed species from becoming dominant.  In monocropping systems, it’s common for one or two particular types of weed to thrive in the conditions that crop creates, and after several years, those weeds can become highly established and even resistant to herbicides.  Changing the crop means changing the conditions, which stops unwanted species from getting a strong foothold and makes all weeds easier to control.

4. Pest and disease control

Much like with weeds, specific crops are vulnerable to specific types of pests and disease.  If you monocrop, the life cycles of those pests and diseases will quickly become established and can be increasingly difficult to break.  Switching crops prevents these cycles from occurring, giving your crops and soil a break from pest and disease problems that could otherwise become endemic – but also attracting beneficial insects and bacteria that work to keep soil ecosystems in balance long-term.

What does a typical crop rotation look like?

Crop rotations can vary a lot depending on climate, soil conditions and the farmer’s business objectives.  Here’s a very simplified example of a crop rotation and the reasons for the sequence:

Year 1: Legume Crop

Legume crops like peas and soybeans are nitrogen-fixing plants. They have a symbiotic relationship with nitrogen-fixing bacteria in their root nodules, allowing them to convert atmospheric nitrogen into a form that can be used by plants. Planting legumes in the first year of the rotation enriches the soil with nitrogen, making it available for subsequent crops without the need for synthetic fertilizers.

Year 2: Grass Crop

Corn, wheat and sorghum are all examples of grass crops.  They are heavy nitrogen users and will therefore benefit from the nitrogen fixed into the soil by the legumes in year one, reducing the farmer’s dependence on synthetic fertilizers.  Grass crops also have a different pest and disease profile than legumes.

Year 3: Root Crop

Root crops like potatoes, carrots and other vegetables are typically grown last in a rotation because they are less demanding on soil nutrients and also because they naturally break up the soil structure as they grow, and during harvesting.  Since legumes prefer a loose soil structure, this is a useful characteristic.  As with other crop groups, the pest and disease profile of root crops is different, and helps to break the cycle.

Many crop rotations are more complicated than this – particularly when cover crops are added in between cash crops or during fallow periods. The length of rotation can also vary – some farmers will grow their main cash crop for several consecutive years before going into a rotation. 

What planting and tillage tools are needed for successful crop rotation?

When it comes to tillage and planting in a crop rotation, efficiency is really important.  The more complex your rotation is, the less you can afford downtime, so it’s important that tools like disc blades are long-wearing to avoid frequent changing, especially halfway through a busy season!

Soil compaction can be a problem in complex rotations due to the sheer number of passes required to plant and harvest multiple crops each year.  Thinking about how you can reduce passes – by switching to no-till, or using multi-purpose machinery – can reduce the amount of compaction.  It’s also really important to ensure your machinery and parts are well-maintained, with appropriate tire pressures and sharp blades to reduce drag.

Precision planting is also important, and you can save valuable time and energy with Guaranteed True® seed disc openers from Wearparts – we test every assembly in-house to some of the tightest wobble and lope tolerances, so you don’t have to. 

To find out more about how quality parts from Wearparts can enhance your crop rotations, get in touch.

As fall arrives across the US, the Midwest and other crop-producing states are preparing for harvest and thinking ahead to the winter months – which means sowing winter wheat, and also cover crops.

Research shows that cover crop adoption in the US has increased dramatically over the last decade, with 2021 levels at four time what they were in 2011 – but overall, cover crop adoption remains low at just 7.2% of available cropland.  

The recent increase in cover crop planting has been attributed to federal and state incentives for farmers – for example, the USDA’s Environmental Quality Incentives Program, which invested over $14 billion in conservation practices from 2010 to 2020.  

But with many farmers still choosing not to plant cover crops despite their potential benefits for the soil, we’re taking a closer look at an ancient farming practice that is coming back into fashion today.

What is a cover crop?

A cover crop is any crop that is planted in between ‘cash crops’ with the main goal of protecting or nourishing the soil.  Unlike cash crops, cover crops do not get harvested or sold – they are terminated at a specific point in their growing cycle and typically incorporated back into the soil either mechanically or naturally, although some are used as forage for animals.  Cover crops can also be referred to as ‘green manure’.  Ancient Chinese and Greek manuscripts suggest that the use of green manure has been around for thousands of years.

What are the benefits of cover cropping?

Planting a cover crop has numerous benefits for the soil and therefore, for future yields when cover crops are followed by cash crops like corn or soybeans. Here’s a look at the key benefits:

1. Prevention of soil erosion

In all but the southern states, winter weather typically brings with it harsh conditions involving wind, rain, snow and ice that can wreak havoc on exposed soil.  A 2022 study by the University of Massachusetts Amherst found that farms in the US breadbasket have lost on average 2mm of soil per year since the land was settled 160 years ago – that adds up to 57.6 billion metric tons of soil. 

Cover crops act as protection that prevents erosion – surface vegetation prevents soil being lifted by wind or washed away by surface runoff, while root structures bind the top layer of soil together and absorb excess water, reducing the risk of waterlogging.

2. Enhanced soil fertility

Cover crops are designed to be incorporated into the soil after they are terminated – either by being mechanically chopped and tilled in, or simply being left to decompose on the surface.  Either way, they add much-needed organic matter to the soil which can enhance its ability to retain moisture and nutrients. 

It’s common to use nitrogen fixing crops such as legumes as cover crops.  Nitrogen fixing plants have roots that are colonized by organisms that can trap and store atmospheric nitrogen.  When plowed into the earth, these plants are excellent at replacing the nitrogen that is removed by many cash crops, such as corn.

3. Weed management

Following harvest, it’s incredible how quickly weeds can colonize a field.  The difference between allowing weeds to cover the soil and deliberately planting a cover crop is that the farmer can control the outcome ahead of spring planting. 

While many weed species can drain the soil of nitrogen and other nutrients, as well as being extremely difficult to get rid of once established, cover crops are specifically selected because they’re easy to manage and good for the soil. 

By their very definition, cover crops provide excellent soil coverage which prevents weed seeds from germinating – meaning that in spring, there’s less work to do to get the main crop in the ground.

What are the challenges of cover cropping?

Like any planting cycle, cover cropping involves additional work and demands that farmers pay even closer attention to the timing of their planting and harvesting cycles in order to get the maximum benefit of a cover crop.

Cover crop seeds also cost money, and some farmers may feel that the benefits can be matched by applying artificial fertilizers, especially if they live in an area where soil erosion is less of a problem.  Cover cropping may also incur additional costs for farm labor, fuel and equipment.

A big barrier to the use of cover cropping is lack of knowledge and perceived risks.  Although this method has been around for generations, it has fallen out of favor in the last century and therefore farmers may not feel confident in trying something that is new to them and their land.

What are the main types of cover crop in the US?

There are three main groups of plants that are typically used as cover crops in the US:

Which cover crop should I plant?

The type of cover crop selected will depend on the soil type and environmental conditions, but also on the type of cash crop the farmer wishes to grow next.  

For example, grass cover crops are often used where soil erosion is a problem – for example in locations where heavy wind and rain is a problem – and where the subsequent crop requires a good soil structure and little weed competition, such as corn and soybeans.

Corn and soybeans are also fairly demanding on soil nutrients, so a farmer who is less worried about soil erosion and more worried about fertilizer costs might opt to plant legumes over winter before putting in his spring corn or soybeans.  Legumes are also ideal cover prior to vegetable crops like peppers and tomatoes, which need a lot of nutrients.

Broadleaf non-legumes are often used as cover on mixed farms where they are a useful source of forage for livestock, but they also have disease and pest reducing properties that make them a useful cover crop prior to the planting of tender vegetables including lettuce.

What happens to cover crops in spring?

Prior to planting of the main cash crop, cover crops are typically ‘terminated’.  This can be done by mowing or tilling, use of herbicides or sometimes simply by turning livestock into the field where they will eat the crop and fertilize the soil with their manure. Some cover crops will die back naturally when the coldest winter weather arrives, and can easily be tilled into the soil before planting season begins in spring.

Termination of cover crops is timed carefully to ensure the plants have achieved optimal maturity – where they have accumulated enough organic matter to enrich the soil, and usually before they go to seed.  

Tools for the task include vertical tillage blades, high speed compact discs and coulter blades.  The type of equipment used will depend on the cover crop – fibrous grasses typically demand a more aggressive approach and will decompose more slowly than legumes, so the approach to residue management may be different.  Whatever your requirements, Wearparts can offer a quality alternative to OEM parts, with options to suit all machinery brands and soil types.

More information on cover crops

For more information about cover crops and available incentive schemes in your area, visit the USDA website.  For advice on tillage tools to enhance your crop rotation, manage residues and tackle soil quality challenges, get in touch with Wearparts directly or find your nearest Wearparts dealer.

Sweeps – or shovels and plows as they’re known in some parts of the US – are an important tillage tool, used at various points throughout the farming year to aerate and condition the soil.

A sweep is a v-shaped or curved wing metal blade, typically designed to attach to the shanks of a row crop, or field cultivator or chisel plow.  The sweep penetrates the soil to a fixed depth, and then as it is pulled through the soil it lifts and turns over the top layer.

The primary purpose of agricultural sweeps in tillage farming is to disturb the top layer of soil, break up any compacted soil, and incorporate crop residue or cover crops into the soil. This process helps to improve soil aeration, water infiltration, and nutrient availability, which are essential for healthy plant growth.

But there’s another important use for sweeps, and that’s weed control.  With planting season now well underway, it won’t be long until farmers have to start thinking about suppressing weeds to ensure their crops receive optimal levels of light, nutrients and water.

How can sweeps be used to control weeds?

Controlling weeds with sweeps is referred to as mechanical weed control.  It can be done prior to planting, or during the growing season.  Some farmers will do both in order to give their crops the best chance of successful germination and growth.

Mechanical weed control is suitable for organic systems, and if done meticulously, can negate the use of chemical herbicides.  Farmers may also use mechanical weed control in conjunction with herbicides.  Here are some of the ways sweeps can help farmers to control weeds in their crop fields:

Weed removal

Using sweeps can physically uproot or sever young weeds as they push up through the soil.  The young plants will then wither and die before they have a chance to become established or set seed.  Shallow sweeps are usually sufficient for this task because the plants are still tender with poorly developed root systems, so soil disturbance is minimal.  Regularly using sweeps can help farmers keep on top of weeds without the need for any other treatments.  

Incorporating cover crops

Planting a cover crop is one method farmers can use to prevent soil erosion and reduce weed problems.  Cover crops may be planted in the season before the main crop (for example, winter wheat), or they can be planted a short time before the main crop is due to be planted.  In the latter case, the most common crops are fast-growing legumes like clover, peas, soybeans and alfalfa.  These plants accumulate biomass quickly, crowding out weeds.  The cover crop is terminated right before planting of the main crop, and the residues are incorporated into the soil using sweeps.  This process is sometimes called ‘green mulching’.

Disturbing weed roots

For more established weeds, sweeps are a great way to cut through their root systems beneath the soil, preventing the plant from absorbing water and nutrients so that they wither up and die.  It’s important to use strong, sharp blades and set the sweeps to a sufficient depth where they can cut through tough tap roots effectively.

Enhancing herbicide application

In some cases, sweeps are used in conjunction with herbicide application. The sweeps disturb the soil, which allows herbicides to reach the weed roots more easily. Combining mechanical and chemical weed control can significantly reduce the farmer’s dependence on expensive herbicides.

What’s the best type of sweep for weed control?

Sweeps come in a variety of shapes and widths for different tillage applications.  Some are very narrow and pointed, while others have a shallower angle for less aggressive cutting.  Sweeps also come in different depths.

Sweep shape

The angle and crown of a sweep wings will determine how it moves through the soil.  Narrower winged sweeps are subject to less soil resistance so they can move more quickly and easily, especially in row crop cultivation.  These sweeps are suitable for shallower cutting.  Sweeps with a steeper angle will be met with more soil resistance and may be used in very dry or rocky conditions, so they move more slowly and smoothly, but are only suitable for use at shallow to medium depths.  

Sweep width

The width of a sweep determines how much ground it can cover in a single pass.  Wider sweeps typically have a shallower angle, and vice versa.   

Sweep depth

The depth of a sweep is determined by the length of the stem or mounting bracket.  A longer bracket will allow the sweep to penetrate more deeply, as will increasing the downward pressure on the plow or cultivator itself.  Some machines have adjustable shanks so that farmers can get variable depths.

Narrower sweeps are better for cutting through the roots of established weeds.  Wider, shallower sweeps are better for removing young weeds, or incorporating cover crops.

What should I look for when choosing sweeps for my machinery?

The most important thing is to ensure the sweep you choose are compatible with your machinery brand.  At Wearparts, we offer a range of sweeps to fit all common chisel plow, row crop, and cultivator brands, including FallowMaster.

The second thing to think about is the durability of the sweep versus the cost.  Think about your soil type – is it dry and rocky, or heavy clay?  Perhaps it’s loamy and easy to work.  If you’re going to be working in difficult soil conditions, it’s worth investing more in heavy duty sweeps that can withstand the intense friction and loading that will occur as you pass through the field.

In these conditions, cheaper sweeps are usually a false economy – they wear much more often, so you have to replace them more frequently, and you lose valuable time while your machine is down for maintenance.

Hardfaced sweeps

At Wearparts, we use premium-grade materials like boron steel to manufacture our agricultural sweeps.  This gives our sweeps a unique balance of strength and flexibility that increases wearlife and reduces the risk of breakage, while maximizing efficiency even in tough soil conditions.

We also offer custom hardfacing as an option on all sweeps.  You can choose to have your sweeps hardfaced on the top or bottom plus the stem.  CMT Hardfacing is a cold welding process that adds material to the ground-engaging portion of the blade, without superheating the base material.  This stops the formation of weak spots that can lead to premature wear.  Our own independent tests show that our hardfaced sweeps can deliver up to 30% longer wear life in the field.

To find out more about our range of sweeps for chisel plows, row crop and field cultivators, get in touch!