What is Tillage?
Tillage refers to the physical modification of soil with tools and equipment for attaining conditions ideal for seed establishment, germination and plant growth. Tillage can be attained by processes such as cutting, crushing, milling, beating and rebounding. The main objective of tillage is to provide optimum aeration for the exchange of gases in the seed and root regions. Apart from the gaseous exchange, it also aims at providing adequate lighting to the seedling, a non-crusted soil to support seedling emergence and ideal conditions for root elongation and proliferation. This practice promotes water flow to seed and seedling roots through adequate seed-soil contact. It also controls pests and pathogens.
There is a risk of soil structure being destroyed in conventional tillage. To minimize the wastage of energy and protect soil structure various new concepts of tillage have been introduced such as minimum tillage, zero tillage and stubble mulch tillage.
Tillage in Organic Agriculture
It has been found that organic farmers carry out more tillage operations as compared to their conventional counterparts. They are highly dependent on tillage for weed control. Nevertheless, skilled organic farmers who have a thorough knowledge of equipment operation, soil conditions, the timing of tillage and types of tillage to be implied for the crops grown on rotation can minimize the negative effects of tillage.
Organic farming systems, to conserve soil while effectively controlling pests, adapted no-till systems. Studies have proven that no-till systems are effective in controlling soil erosion and run-off and maintaining yields on par with conventional tillage. Also, it protects the physical, chemical and biological structure of the soil better than conventional tillage.
Is No-Till Practically Possible in an Organic System?
Yes, controlling weeds with no-till is practically possible in organic farming, of course, without using herbicides. The organic farmers are practising to terminate a cover crop mechanically by methods such as mowing, undercutting or rolling which let the cover crop remain under the soil acting as weed-suppressing and moisture-retaining mulch. This is followed by seeding or transplanting the main crop into the terminated cover crop. This method has been successfully implemented for crops such as corn, soybeans and vegetables.
How Does No-Till System Benefit Organic Farming?
- It saves fuel, time, capital and labour as the number of tractor passes over the field is significantly reduced
- Controls soil erosion and maintains soil structure
- Effectively control weeds in a sustainable way
- The moisture retained cover crop mat regulates the soil temperature in mid-summer
- Leguminous cover crops produce nitrogen to the cash crop
How bad is No-Till in Organic Agriculture?
- No-till results in nitrogen tie-up especially when using crops with higher C: N ratio
- The temperature of soil may remain too cool in the spring
- A lot of water may be consumed by the cover crop and retained within it
- The success depends highly on the size and properties of cover crop
- The cover crop should produce large amounts of biomass for rolling. If rolling is not executed well, the crop may grow back
- Can allow weed growth if the cover crop doesnt have weed-free stands
- Allows the growth of plant damaging pests
- Deviating from the standard protocol would result in less than perfect results
Online Course in Agribusiness at James Lind Institute
To learn more about soil fertility in organic farming system, enroll yourself in an online training program name Professional diploma in Organic farming and food production which is being launched at James Lind Institute. This course acquaints you with various other aspects of organic farming including crop agronomy, the role of animal health and nutrition in organic farming and environmental impacts along with a broad overview of sustainable agriculture and food security in African countries. The globally accredited and industry specific training fine-tunes your skills to match the needs of the ever-growing market. James Lind Institute launched online training programs in Organic farming and food production. For more details, please visit www.jliedu.com