Pasture Cropping: A Holistic Approach to Grain and Pasture Production

Pasture Cropping: A Holistic Approach to Grain and Pasture Production
Contributor
Contributor
External Guest Writer
June 1, 2021

The current processes involved in traditional agriculture has led to large-scale soil degradation in numerous locations across our planet. Soil degradation and erosion is a troublesome side effect that has numerous implications for our ecosystem. 

Not only does it lead to an increase in sedimentation and pollution in nearby water sources like rivers and streams, but it can also directly impact the flora and fauna of a region. 

In order to counter the ill-effects of poor traditional practices on the soil, pasture cropping is seen as the next big movement by farmers among other sustainable agricultural methods. We conduct a deep dive on this topic in the article below, discussing the specifics of pasture cropping, its history and development, how it works, its many different techniques, and the benefits, advantages, challenges, and drawbacks related to it.

What is Pasture Cropping?

It is seen that one of the best ways to improve the condition of the soil in a region is by developing root systems that belong to a diverse set of plants. Actively rearing these root systems for a majority of the year can greatly boost the conditions of the soil. 

This is where the process of pasture cropping comes in. It can be described as the coming together of the grazing and cropping process in order to result in the symbiotic benefit to both systems. This can have enormous environmental and economic impact on a region.

Pasture cropping is the zero till sowing of various annual crops that can result in the creation of living perennial pastures. This process can also be described as perennial cover cropping.

Executing on pasture cropping relies on the no till sowing of crops into a window of dormancy of a pasture. This can involve:

  • Sowing summer crops into pastures that are active in winters
  • Sowing winter crops into pastures that can be active in summers
  • Sowing forage crops in either summer or winter seasons
  • Growing cereal or broadleaf crops or creating a mix species planting

The History and Development of Pasture Cropping Systems

Pasture cropping is a relatively new type of farming that has only been in development since the 1990s. However, the process of sod seeding of various annual crops to create perennial pastures in order to increase the amount of winter forage is one that has been practiced for a long time. This is especially true in areas that have winter dormant pastures, as they utilize various techniques involving the “roughing in” of numerous cereal crops into existing pastures. This technique has been in practice since the 1960’s. 

A revival of pasture cropping occurred in Australia in the early 1990s. This was due to the efforts of Darryl Cluff and Colin Seis who hail from the Gulgong region of Australia. These two individuals had become irritated with the traditional no till cropping method employed as a part of their grazing and mixed cropping methods. This was because they had to destroy their pastures with toxic herbicides in order to make space for the new crops. They had to follow this step by actively re-establishing pastures at the end of every cropping phase.

As a result of this traditional method, farmers not only incurred a high input cost, but they also damaged the surrounding environment by causing an increase in soil acidity and salinity in the water table. 

These reasons made Cluff and Seis rethink their current practices, and they realized that some of the native flora in the region such as the native Red Grass went into dormancy during the winter seasons. With this information, Cluff and Seis began to directly drill winter growing cereals into pastures where native crops went dormant during the winter season.

Thus they began to consciously exploit the complementary natural growth cycles of various winter and summer crops. This remains the principle tenet of pasture cropping to this day. 

The researchers began practicing pasture cropping by first growing oats as a relatively inexpensive option to fill the feed gap during winters. Fortunately for them, the oats performed so well that it became evident that this process could be utilized to grow grain crops as well. Not only did the oats grown in this method achieve excellent yields, but they also had a positive effect on the soil and hydrology of the region.

As a result of this experiment conducted in Australia, pasture cropping became a popular method of improving yield for various crops without disrupting the environment. This method soon attracted the attention of individuals who were interested in improving soil carbon levels. This is a key parameter to understand the soil health of a region and to study atmospheric carbon sequestration. 

Studies have shown that perennial pasture-based systems can be an incredibly effective method of improving the organic carbon gains of the soil. The continuous growth of greenery and the favorable soil environment create conditions that allow for the heightened transfer of carbon from the plants to the soil with the help of the root system.

How Does It Work?

One of the biggest reasons behind the success of pasture cropping is the underlying relationship between cool season plants and warm season plants. There is a fundamental difference in the internal make-up of these plants. This has to do with the number of carbon molecules and the manner in which they affect the glucose production process of the plant.

Cool season plants such as rice, oats, barley, and wheat tend to grow early in the season, but they soon become less active and tend to move towards dormancy as the temperatures begin to climb and the intensity of the light increases. 

Warm season plants including the likes of corn, sugarcane, and millet, stay dormant until they sense the temperatures become warm enough to boost their growth. Thus we see that both these types of plants create their own niches based on the seasons.

Pasture cropping is a process that heavily relies on the niches of these plants. As the warm season plants stay dormant in the winter season, the seed of a winter crop is sown using the no-till drilling system straight into the pasture of the warm season crop.

As the spring season emerges, we see the cool season crops begin to grow steadily. IF the right amount of nourishment and resources are provided to these cool season crops, farmers stand a chance at harvesting these plants before the warm season plants resting below the soil begin their growth cycle.

When the cool season crops are removed during the summer time, they will further stimulate the growth of the warm season plants as there is lower competition in the region. Placing a mix of deep and shallow-rooted crops also helps the plants access the water resources differently, thereby leading to even more reduced competition in the farm.

Activity in the Soil

In order to fully understand the success of the pasture cropping method, it is also important to understand the activity occurring in the soil during this process. The cool season cereal crops help to infuse the soil microbes with sugars, and this helps feed various species of fungi, protozoa, and nematodes. 

As this occurs when the warm plants are dormant, it helps to boost the soil fertility in the region substantially. Warm season crops are not competent enough to kick start this process, but when coupled with cool season crops across the year, they help to greatly boost the soil fertility with their sugars.

Additionally, this process also improves the nutrient cycling and leads to an improved water cycle as well. All these activities in the soil also lead to a boost in the nitrogen content as well as the organic matter to the soil, and this can help build humus. 

Using the no-till drill also helps aerate the soil, and this can be useful in allowing oxygen and water to infiltrate the soil in an improved fashion.

Grazing Animals

Using grazing animals to help prepare the warm season crop field before the drilling begins is also a key step in pasture farming. Grazing animals tend to hit the sections with perennial pastures, and this can be problematic for the warm season crops in a good way. It stunts their growth ever-so-slightly during the emergence of summer, and this gives the cool season crops a chance to finish their growth cycle in time.

Taking a large herd of sheep to pastures with warm season plants in a timely manner prevents them from overshooting and overshadowing the cool season plants still growing in the farm. The animals also play a major role in controlling the growth of weeks, offering nutrition to the soil through the litter, and removing any traces of dry plant residues from the farm.

The use of sheep in such a manner has been seen as controversial in some sections of the community, largely due to the concerns related to soil compaction. This, however, is only a problem in regions where there are low levels of ground litter and cover, or if the ground is extremely wet. If the perennial pastures and ground cover is high, then the pasture-cropped paddocks have been shown to create very little soil structural issue or compaction.

Sowing Techniques

The sowing techniques employed in this method tend to play a massive role in the end results. It is important to graze the paddock to about three or four inches before sowing, as well as create as much litter as possible.

Using herbicides to control the growth of weeds whenever necessary, and using no-till equipment to sow at the ideal depth and row spacing is also key to this process. 

Conducting a soil test to determine the perfect crops that can be grown in a farm is also another important and overlooked element of pasture cropping. Avoiding fertilizers as much as possible during the growth cycle will also boost the health of the crops and the ecosystem. Using plows in this method is a massive no-no as it disrupts the crops lying dormant in the soil.

The Different Techniques and Variations of Pasture Cropping

Pasture cropping in general is associated with various techniques and variations based on the plants you intend to grow. Some techniques encourage the application of herbicides before the sowing section in order to reduce the competition posed by annual weeds. Other techniques follow the “advance sowing” approach where the plants are gradually dried well before the autumn season without the use of any herbicides. 

While the sowing methods applied may vary greatly based on the climate and the type of crops, the principles of this method largely remain the same. It is crucial to minimize any damage caused to the perennial pasture base while simultaneously ensuring that a good soil-seed contact is established.

The Benefits of Pasture Cropping

Pasture cropping has been widely adopted in several parts of Australia and various other regions of the world. This is because of the large number of benefits and advantages associated with the practice. We discuss some of these factors in the section below:

Improving Profits

In the practice of pasture cropping, it is possible to maintain the traditional crop yields while also simultaneously reducing the dependency on fertilizers used in crops and pastures. In fact, the use of fertilizers in the pasture-only phase has been entirely removed from this process. Crop fertilizers are also drastically reduced in pasture cropping. This is done by slowly reducing the fertilizer rates over time so as to not affect the grain yield. Maintaining the grain yield is key to improving soil structure, nutrient cycling, and soil health.

Farmers belonging to the traditional cropping enterprise will also note the elimination of herbicide application during the summer seasons. Instead, the summer season is utilized for grazing as the stock can produce from the paddock for an additional six month period. This technique therefore leads to a reduction in costs and a boost in production.

Farmers who practice a straight grazing system stand to make extra income from the extra feed or crop when growing fodder crops. This also leads to various qualitative improvements in the field as well as pasture diversity. As the pastures keep improving, it eliminates the need to re-sow all the pastures that have been worn out. This also helps to save money by not having to engage in expensive pasture renovation processes.

Studies have shown that farmers can expect at least a 70% drop in their fertilizer input costs with pasture cropping, as well as a complete elimination in input cost of pasture fertilizers in non-crop years. 

This method also eliminates the use of fungicides and insecticides over time, as well as all forms of herbicides. These chemicals are quite expensive when used across the year, and eliminating these costs result in huge savings for the farmers. 

Reducing Risk

As farmers have to put in a smaller amount of input costs for their crops at the start of the season, the financial risks connected with the probability of a dry year are greatly reduced. This is especially true in regions where rainfall has started to destabilize rapidly. 

Reducing Pesticides

The overall dependency on pesticides, insecticides, and herbicides in this process is greatly reduced. This is a major positive not just for the people who have to work in such conditions, but also to the environment in general. 

Traditional cropping systems have recently significantly heightened their utilization of herbicides in order to protect the crops. The use of double knock strategies especially promotes the use of toxic herbicides such as paraquat. 

As the summer lull is eliminated in pasture cropping, it also reduces the need to use pesticides on the lands. The overall reduction of such toxic chemicals is a great result for all parties concerned in the end.

Improving Soil Conditions

The improvement in the conditions of the soil is truly one of the biggest benefits and advantages of using pasture cropping techniques. This is largely due to the continuous growth of root systems by the various winter and summer crops grown in pasture cropping.

As there are roots developing within the soil across the year, it leads to an increase in the release of various sugars from these actively developing roots. This helps to greatly boost the microbiology of the soil in a region. 

Thus the increase in the microbiology helps to facilitate various vital improvements in the soil structure and also improve the carbon levels in the soil. The fallow summer period brought on by traditional farming methods conversely leads to a reduction in the microbiology of the soil. 

The fact that farmers grow various varieties of crops in pasture cropping also brings added benefits to the soil conditions. The sheer variety of root systems growing in the soil helps to facilitate the growth of various types of soil microbiology. This is a key element that leads to the sequestration of carbon through the soil and makes various nutrients available to plants when they need them the most.

In one study, the use of pasture cropping techniques led to numerous benefits in terms of soil conditions. The total fungi in the region increased by nearly 900%, while the bacterial, protozoa, and nematode levels also improved by 350, 640, and 1000% respectively.

Fungi are important to the plants because they absorb the sugars to produce various elements, whereas the protozoa and nematodes are responsible for consuming bacteria that can be harmful to plants.

Another study revealed that using pasture cropping led to an increase of over 200% in the organic carbon levels in the soil. Of this, nearly 80% of the carb was seen to be in a stable humic form, and only a small percentage was in the labile form. This is crucial information as the labile carbon may get lost over time, but the humic carbon sticks to the soil for several decades if not more.

Even the depth of the penetration of carbon levels were seen to be improved due to pasture cropping, and this further highlights the importance of allowing root systems to develop within the soil across the year.

How to Get Started with Pasture Cropping

Before you get started on pasture cropping processes, it is vital that you determine your priorities. You can utilize this for various processes that include:

  • Soil improvements: This helps to improve the nutrient levels in the soil and heighten carbon levels. It also assists in cutting down the use of fertilizers
  • Flexibility: Your lands will be available for both cropping and grazing instead of having to limit your activities to one or the other process
  • Grain yield: You can look after the soil in a manner that greatly boosts grain yield
  • Fodder: Pasture cropping can be used to fill the stock feed gap in a pasture

The Planting Portion

The first step to getting started with pasture cropping has to do with the planting process. Here, the pastures of the farm are either crash grazed or pre-grazed before the crop sowing period in order to reduce the overall biomass of the pasture. This also helps to let light penetrate through the top layers to access the emerging crops, as well as adds urine and manure to the paddock.

A no-till sowing approach is then utilized on the dormant pastures in a way that also prevents weed germination (by retaining good groundcover). It is important to pay attention to various aspects of sowing and this includes sowing times, variety, using the right equipment, establishing a competent set up, and so on.

The emergence of crops is seen to be slightly slower in the no-till sowing method, but it has a positive impact on the various plants that grow on this soil across the year. 

In terms of row spacing, there is no yield reduction up to 12 inches, but there is little reduction seen at 14 inches. Wider row spacing is generally seen as a disadvantage to various fodder crops, but the ideal amount of row spacing also tends to vary based on the climate of a region. 

It is also important to consider the growth style of the crops you have chosen for this process. Some of the taller crops can end up being more successful in pasture cropping when it comes to the harvesting season. 

Using Fertilizers

As the soil health increases, you will be able to reduce the amount of fertilizers you are using in the farming activities. It is, however, crucial that you wait for the soil health to improve before you begin to cut back on the fertilizers. Thus the ideal approach would be to utilize the same amount of fertilizers you would normally utilize in traditional methods of farming when conducting pasture cropping during your first year.

With each passing year going forward though, you can look to cut back on the fertilizer use by 10-15% based on the condition of the soil. You can eventually reach a point where you cut down fertilizer use by as much as 80%, although it is realistically not possible to eliminate fertilizer use entirely in this process.

Discussing Herbicides 

It is important to carefully choose your herbicides before application. If your aim is to maximize and optimize your grain yield, you can opt for an in crop herbicide to tackle various broadleaf weeds. If you want to boost your grain crop yield though, you can look to focus on grass species by using an in crop broadleaf selective herbicide.

You can look to use selective herbicides to tackle summer control weeds when growing summer crops like melons. 

For winter crops, farmers in the past used to utilize glyphosate during the planting process once all the summer grasses have shut down. You can avoid this entirely and just use a crash graze method in order to support the winter pasture species like weeping grass and clovers.

Challenges and Drawbacks

  • The process of transitioning from high levels of fertilizer inputs to low levels can be a slow one. Transitioning too quickly will be damaging to the soils and may cause numerous dysfunctions
  • If there is a development of warm weather early on in the spring season, it can make the process of pasture cropping challenging
  • If you fail to graze the pastures down before planting a new batch of crops, it can lead to an increase in root competition and shading. This invariably affects the crop yield during harvest season

Moving Towards Greener Pastures

Traditional farming methods have carried us across several generations worth of progress, but now the very same mechanisms have begun to stunt our growth as a species. Not only that, but it has also become harmful and toxic now as well.

Pasture cropping and other modern methods of farming can help alleviate the stress caused by traditional farming methods on the soil. As we slowly transition from the older methods to our newer systems, it is key to retain the concepts of sustainability and environmental conservation for the sake of our future generations.

See also: Improving Soil Quality with Biochar Technology