Contour Farming Advantages What It Is And Why We Use It
What is contour farming
What is contour farming?
Contour farming definition
Contour farming involves farming row patterns as level as possible around a hill. Thus, the row patterns do not go up and down but are around the hill.
By creating rows around the hill you will generate the equivalent of small dams that will slow waterfall and help to increase infiltration of the water into your soil while reducing erosion.
For contour farming to be effective, your rows need to be as level as possible around the sloping hill.
It has been getting used for centuries in places where irrigation farming is in need.
Creating your crop rows around the slope of your hill provides you with two significant advantages. Your soil will capture twice as much rainwater and can reduce soil erosion by as much as eight times.[2]
How did contour farming start?
Contour farming starting gaining popularity in the United States during the 1930s.
It has been getting used for centuries in many other parts of the world.
But once it was proven to reduce fertilizer loss, power and time consumption, wear on machines, increase crop yields, and reduce erosion, it quickly gained popularity.[1]
Efforts by the U.S. Soil Conservation Service to promote contouring in the 1930s as an essential part of erosion control eventually led to its widespread adoption.
Strip cropping gets commonly implemented in contour farming.
The farmer will arrange their crops, so strips of meadow or small grain are alternated with a strip of row crops.
Rows of crops get limited to no more than half of the field usage. In addition, using meadows allows the land to slow water runoff while increasing the rate of water infiltration, traps sediment, and helps to provide surface cover.
Contour Strip cropping uses the beneficial effects of contouring and crop rotation.
Generally, farmers also implement terraces to provide even more erosion control with better stormwater management.
Alternating your crops with growing legume types (such as alfalfa or clover) getting planted in the meadows can help you provide the needed nitrogen to your soil. In addition, using a secondary crop to provide nutrients like legumes enables you to reduce the volume of fertilizers required.
Another benefit from farmers alternating their crops is that it naturally breaks the cycle of weeds, insects, and disease, reducing the number of pesticides used.
Contour Buffer Strips
Similar to strip cropping, contour buffer strips use grass or some other permanent vegetation to trap sediment or nutrients from getting washed away. Another difference is that the buffer strips are going to be more narrow compared to strip cropping.[1]
Buffer strips must be at least 15 feet wide. The width will also depend on the slope, soil type, field conditions, climate, and erosion potential.[8]
It is common for buffer strips to consume 20 to 30 percent of the slope area.
The vegetation is kept high in sprong to aid in slowing runoff.
How does contour farming reduce soil erosion?
The ridges that get formed by the contoured rows slow down the rate of water flow. With a reduced water flow, you reduce the soil's hazard for erosion.
To reduce soil erosion even further, you can plant vegetative hedges, bunch grass, or shrubs on the contour at regular intervals.[6] The addition of this vegetation act as porous filters reducing the carrying capacity.
The runoff water is not usually reduced but has dramatically reduced the percentage of soil loss, even better than conventional tillage systems.[6]
For grass strips at half to one meter were also shown to be highly effective at reducing erosion over four years.
These hedges can increase the time for water to infiltrate into the soil and facilitate sedimentation and deposition of eroded material by reducing the carrying capacity of the overland flow.
Contour Farming Irrigation
Irrigation of crops still gets done using standard methods of using pipes, canals, sprinklers.
Areas that use contour farming methods can conserve water usage because of how much better contours allow rainwater to seep into the soil.
Where is Contour Farming Used?
Contour Farming ConditionsContour farming gets used in areas where the slope of the land is anywhere 2 to 10% and rainfall is not excessive.
Suppose the land slope is greater than 10% or receives excessive rain. Then, contour strip cropping gets implemented to help further prevent soil erosion.
Common Contour Farming Crops Types
- 1) Corn
- 1) Legumes
- 1) Grass
- 1) Soybeans
- 1) Wheat
Contour Farming Advantages and Disadvantages
So what are the contour farming pros and consContour Farming Benefits
- 1) Soil Erosion
- 2) Water Quality gets improved by controlling sedimentation
- 3) Enhances and maintains favorable soil structure
- 4) It helps to keep soil fertility high by preventing downwash.
- 5) Minimizes surface crust
- 6) Favors a high water infiltration rate
- 7) Reduces water runoff rate and amount
- 8) Directs and captures rainwater.
- 9) Creates microclimates of sunlight and shade.
- 10) Allowing us to utilize hills allows us to maximize land usage for growing crops.
- 11) Increase crop yields by 10 to 15 percent.
- 12) Reduces fuel consumption and is easier on equipment
Contour Farming Disadvantages
- 1) When dealing with more prolonged and steeper slopes, farmers need to move to strip cropping.
- 2) Herbicide carryover may be a problem.
- 3) Grassed waterways need to get added in areas where runoff concentrates.
- 4) Irregular slopes may require more than one key contour line.
- 5) Suppose the amount of rain exceeds your contouring system's surface detention capacity. In that case, it can accelerate erosion and may even cause gulling.
Conclusion
Contour farming is a valuable tool to help protect our soils from erosion.
To maximize soil protection, adding other processes like intercropping, buffering, and cover crops can further help reduce soil erosion.
The added biodiversity will also help to keep the fertility of our soils high.
You can even add contouring to your gardens if you have a hilly area. The same benefits seen in large-scale industrial farms will also carry over to your home garden.
To get the maximum benefit, farmers will implement contouring with other sustainable agriculture methods like crop rotation, intercropping, cover cropping, etc.
[1]https://www.britannica.com/topic/contour-farming
[2]https://www.gettingmoreontheground.com/2016/07/26/contour-farming-increases-soil-moisture/
[3]http://www.envirothonpa.org/documents/WSS_Intro_to_Soils_part2.pdf
[4]https://www.nrcs.usda.gov/wps/portal/nrcs/detail/nj/technical/cp/?cid=nrcs141p2_018675
[5]https://www.nrcs.usda.gov/wps/portal/nrcs/detail/null/?cid=nrcseprd414214
[6]http://www.nzdl.org/cgi-bin/library.cgi?e=d-00000-00---off-0ccgi--00-0----0-10-0---0---0direct-10---4-------0-1l--11-en-50---20-about---00-0-1-00-0-0-11-1-0utfZz-8-00&cl=CL3.6&d=HASH010c4f75c25bd24df4cab278.10.2.5>=1
[7]https://www.tenthacrefarm.com/contour-gardening-minimize-irrigation/
[8]https://www.nrcs.usda.gov/wps/portal/nrcs/detail/wi/technical/cp/?cid=nrcs142p2_020770