No till versus tilled soil drain water
What is Conservation Agriculture?
Conservation Agriculture (CA) is a set of soil management practices that minimize the disruption of the soil's structure, composition and natural biodiversity. CA has proven potential to improve crop yields, while improving the long-term environmental and financial sustainability of farming.
How do you practice Conservation Agriculture?
Avoid mechanical soil disturbance to the extent possible. Maintain or improve soil organic matter during rotations until reaching an equilibrium level. Maintain organic cover through crop residues and cover crops to minimize erosion loss by wind and/or water. Maintain balanced nutrient levels in soils.
Why bother with Conservation Agriculture (CA)?
In conservation agriculture, we aim to put soil health at the heart of everything we do. This means not just focusing on the ph, N,P and K status of the soil, but looking at the soil’s physical, chemical and biological health in totality. There are excellent agronomic and environmental benefits to following the CA principles.
Permanent soil cover, either through residues or growing cover crops, has the following benefits:
It prevents the leaching of nutrients, leaving them available for cash crops.
It helps the physical properties of soil. Deep rooting covers till soil without using mechanical equipment. This is cheaper and more sustainable than burning diesel and wearing metal. You may have heard the phrase “roots not iron”, and this is the reason for it.
In our high rainfall climate, bare soil has fine particles washed down through the soil profile until they meet resistance, usually at the cultivation depth, and this causes slumping, pans and poor crop rooting.
High rainfall on heavily cultivated ground leads to erosion of a farmer’s most precious resource- their soil. We are all familiar with rivers turning brown with silt carried from fields and washed away. Cover crops and leaving residues behind help stabilise soil against wind and rain erosion.
Disturbing the soil as little as possible to establish crops has the following benefits, among others:
It costs less. Diesel use, the amount of horsepower/acre, the amount of equipment required all reduce significantly with less disturbance.
It has environmental benefits. Intensive tillage burns the carbon and organic content of our soils. The less we move, the greater the soils potential to hold or increase its total organic carbon content or organic matter. Water quality also benefits from decreased run off.
Organic matter is important in turn for feeding the whole soil food web. From worms and beetles to microscopic organisms and even fungi, less disturbance provides a better habitat for life. Even wild farm birds derive benefit from the additional food and shelter of cover crops. Everyone knows the difference between the soil from a good long ley and soil that’s been intensively cultivated. We all know one of the key differences is down to the lack of disturbance.
Chemically, the more carbon we store in soil, and avoid releasing through intensive cultivation, the greater the positive impact on greenhouse gases.
Diverse rotations also have many key benefits:
Using diverse rotations helps avoid the build-up of problem weeds and diseases.
It can reduce overall costs in the rotation. For example, using legumes helps fix nitrogen that can be used for the following crop.
It is a benefit for pollinators and pest predators to have flowering plants in the rotation.
It is a cornerstone of Integrated Pest Management. This is the reduction in pesticide use by letting nature fight some of our battles for us. Many of our members have managed to remove insecticides completely from their cash crops by building balanced beneficial insect populations into their systems.
Are there many people out there doing this?
While it is difficult to estimate the total number of hectares which employ these methods in Ireland, among our existing membership, we estimate there are c. 8000 hectares of arable and c.1000 hectares of grassland.
Do you have organic farmers as members?
Around 7% of our members are organic farmers. Their experience and knowledge is highly valued within the group.
What’s in CA for livestock farmers?
Many of our members have mixed farms with some form of livestock enterprise. From taking in sheep to graze cover crops on arable fields, to mob grazing suckler, beef and dairy animals, livestock farming is an important part of the CA concept. In fact, the ideal CA farm has some form of livestock enterprise integrated within it. The good concept of mixed farming has decreased in popularity due to increased specialisation. Our grandparents would largely recognise the concepts of grass in rotation, diverse species and the value of livestock manures. These concepts are as valuable today in terms of sustainability of our farms. Utilising livestock manures cuts our reliance on imported chemical fertiliser. Grass in rotation helps control arable weeds and build fertility. Diverse species swards promote livestock health.
Base members discuss these and other strategies to promote soil and animal health and livestock farming sustainability and profitability.
Is Ireland’s climate too wet to not till soil? Does it not need to be loosened and tilled to warm up for crop establishment?
The simple answer to this is no! Take a look around our gallery and you will see great crops of all kinds established with reduced and no tillage. Our members work on soils ranging from deep heavy clays to blow away sands with notable success.