Conservation Tillage BMP's

In the previous 2 posts, here and here we took a look at BMP's for nutrient management in commodity cropping systems. Another aspect of farming operations that need to be evaluated is your tillage practices. Tillage practices and nutrient management are interwoven together and must be planned together to gain the optimal benefit for your farm.


As we all know, until the last decade or so, conventional tillage operations like the moldboard plow was the primary method utilized. Utilizing conventional tillage practices brings with it the following negative consequences:

• Increases soil erosion - This one impact alone has a very negative impact on your farm. Some of these impacts are:
• lower fertility levels
• development of rills and gullies in the field
• poorer crop yields
• less water infiltration into the soil
• more soil crusting
• more runoff in the spring and after storms
• Buries crop residues so that there is slow decay and no surface mulch effect.
• Exposes bare soil to water and wind erosion. May compact the soil beneath the plow.
• Minimal ridging effect.
• High cost per acre

Given the above factors, it makes sense to investigate adopting conservation tillage practices on your farm. Conservation tillage is defined as any tillage system that reduces the number of passes over the field for land preparation and increases the surface residues to protect soil and water loss. That definition is enticing in and of itself as it inherently shows the major benefits you can obtain. But, the question remains, why would I want to adopt conservation tillage? I would start with some very basic questions put together by the US Environmental Protection Agency (EPA):

1. Is soil erosion a problem on your farm?
2. Is the organic matter level content of your soil being depleted?
3. Is soil compaction becoming a major problem on your farm?
4. Are you experiencing reduced yields?
5. Are high operational costs eating away at your profits?

If you answered yes to any of these questions, then you should definitely be thinking about adopting a conservation tillage plan. If you are new to conservation tillage, then try adopting a plan for a few fields to get the feel for it and then adopt farm-wide. This minimizes your risk and allows you to learn what works best for you.

Conservation tillage has a few different approaches; none being wrong or better than the other. 

Types of Conservation Tillage

No-Till

This approach means the the soil is left untouched from harvest to planting and from planting to harvest. The only soil "disturbance" is with an implement that is able to cut through and penetrate the residue like a drill or seed furrow opener. 

No-till beans into corn

Image by: Iowa State

Strip-Till

This method only disturbs the portion of the soil that the seed will come into contact with when planted. There are benefits to strip-till when compared to no-till. Strip-till warms the soil by creating an aerobic condition. It also allows for better seed-to-soil contact while still maintaining a suitable environment to prevent erosion by leaving residue between the rows. 

Researchers at NDSU looking at Strip Till Field

Image by NDSU

Ridge-Till

This method leaves the soil undisturbed from harvest to planting. You then plant the crops in ridges you form using a row cultivator. It is similar to strip-till in that it leaves residue between the rows. 

Ridge-Till Cotton planted in No-Till Corn Residue

Image by University of California

Mulch-Till

This method only allows the soil to be disturbed prior to planting. You can use cultivators, discs, harrows, sweeps, etc. You may even perform deep tillage using a subsoiler. Whatever equipment you use be sure you have at least 30% residue cover or it isn't considered conservation tillage.

Now that we have a broad overview of the methods of conservation tillage, let's look at the factors, or BMP's, to guide you in developing a conservation tillage plan specific to your farm.

Best Management Practices

Soil Characteristics


It is important to match your tillage with your soil. Failure to adhere to this could lead to loss of soil productivity due to erosion and decrease in crop yields. The best way to obtain this information is through a soil analysis at your soil laboratory. When evaluating your soil, pay attention to the following:

1. Internal Drainage: If your soil doesn't drain well and you have a high amount of residue, the soil remains cool and wet for too long. This can cause a reduction in yield for certain intolerant crops like corn. 
2. Soil Fertility: In conservation tillage systems, it is imperative that you have a high soil fertility level. As stated above, be sure to obtain a soil analysis and evaluate the levels of Phosphorous (P) and Potassium (K). If they are low, be sure to raise these levels up to where they should be, otherwise your efforts to adopt conservation tillage will result in decrease in yields.
3. Compaction: This is quite a difficult value to measure; however, it is known that field activities performed on wetter soils increases the compaction. This can result in poor seed-to-soil contact causing decreases in yield and other issues related to the crop vigor in your field. Be on the lookout for indicators such as spindly, short corn.
4. Erosion: The potential is, for the most part, dependent upon the soil texture and rise and run of the slope of you field.

Image by: Carleton College 

Science Education Resource Center

If your field is considered highly erodible you must have at least 30% residue cover to be in compliance with conservation tillage guidelines. Agriculture has made great strides to date in our efforts to reduce soil erosion, but we still need to continue the research and increase adoption rates. 

 

                                               Graph by: USDA-NRCS

Nutrient Management


We covered this topic in our previous posts (links in the first paragraph of this posting). 


Herbicide Program


With conservation tillage comes an increase in weed pressure. You must adjust your herbicide program to fit your tillage plans; just like you do with soil. A good approach, if  possible is to incorporate your herbice application with your tillage operations to minimize runoff.


Equipment

The adoption of conservation tillage practices requires new, state-of-the-art equipment; especially planters. Planters will be required to place seed in soil with heavy residue. The challenge is to maintain good seed-to-soil contact and solid stands. A row cleaner can assist in ensuring you get the proper stand.

Have you started to look into conservation tillage? Have you adopted it already? How long and what are you seeing on your farm? We would really love to hear from you.

Next up in the conservation tillage series is crop production with conservation tillage. Stay tuned and share with your friends.

Resources:
No-Till and Sustainability
NRCS Web Soil Survey
EPA - Soil Preparation

Nitrogen and Phosphorous BMP's

Now that you have created a Nutrient Management Plan (Plan) for your farm let's take a quick look at some Best Management Practices (BMP's) for applying Nitrogen (N) an Phosphorous (P).

Nitrogen Application

Timing 
Applying N when the crop needs it provides yield, economical, and environmental benefits, so in-season application timing is important. The yield benefit is realized by having the right amount of N available for the crop at critical growth stages.

Credit - Iowa State University Extension

The economic benefit is realized with proper timing as the potential for N loss is reduced. This will prevent having to apply N again, thus increasing input costs without any added benefits from the double application. You can also realize a reduction in the environmental impact of N application with proper timing. For example, applying N with a weather forecast of heavy rains soon following increases the potential of N leaching out of the soil.

Nutrient Management Plans - A Step in Developing Best Management Practices

Nutrient Management - the practice of using nutrients wisely for optimum economic benefit, while minimizing impact on the environment.

Photo Source - USDA-NRCS

As with any business, developing Best Management Practices (BMP) is essential to continued success and profitability. As you develop BMP's for your farm, a critical piece to include are Nutrient Management plans. In this post we are going to focus on commodity crops.

Many times BMP's are situational, especially with Agriculture and Nutrient Management. However, there are certain steps that broadly apply to developing a Nutrient Management plan for any farm. Once a plan is developed, the next step, developing BMP's for fertilization, can be put in place. Let's take a look at developing a Nutrient Management Plan