Drainage solutions
Looks at the latest piping and aeration drainage technology
MOST farmers face a frustratingly long wait for ground to dry out at this time of year. The wait begs the obvious question: what options do farmers have to improve drainage and aeration on ground that seems to take an age to dry out?
Assessing and upgrading the drainage system is the definitive answer — but also usually the most expensive one. A properly installed drainage system should last 40-50 years. The key tip from every land drainage expert I talk to is to get the fall in the drain right.
This is crucial for water flow over the lifetime of the drain and should be calculated professionally using laser levels. The fall grade can range from 1pc to 25pc (a 1pc gradient would be the equivalent of a fall of 1cm per metre, while a 10pc gradient would give a fall of 10cm per metre).
What is the approximate cost of installing a modern drainage system?
According to Connacht Agri the cost of their New Choice drainage pipe is €2.84 plus VAT per metre but deals can be done if buying large quantities.
The New Choice pipes are 90pc porous and are wrapped in a polypropylene sleeve (the white part) designed to allow water in at high rates.
They are being used a lot in the west and have good reports thus far. Trenching and backfilling cost €1.50-€2.00 per metre depending on drain depth. At €2 per metre, for example, this takes the total cost of the job including the pipe cost to €4.84 plus VAT/metre.
Those looking at cheaper or shorter term options have some grassland management and machinery-based solutions available to them.
Three systems work together to make soil productive — physical, biological and chemical. Soil scientists agree that the physical condition of soil is the key to efficient biological and chemical activity, which in turn determines the capacity of the soil to produce plant life. Tractors, forage harvesters, pick-up wagons, trailers and manure spreaders have increased in size causing significant soil compaction and negatively affecting the soil’s ability to maintain plant productivity.
A lot of farmers now aerate and/or subsoil their ground to correct compaction issues and improve drainage and grass growth.
If you are going down this route you should never go into a waterlogged field and attempt to subsoil your way out of trouble with a big heavy tractor.
This applies particularly to clay soils, where hasty use of a subsoiler may aid immediate surface water movement but is likely to only exacerbate sub-surface problems.
Subsoil
The best time to aerate or subsoil is when conditions get firm enough so that you are not actually making the situation worse.
Bridgeway Engineering, based in Shannonbridge in Offaly, offer a range of aerators. Options for dry stock and dairy farmers looking for a smaller entry level aerator include a 2.5m or 3m machine, priced at €3,000 and €3,500, respectively.
The smallest model in the
Derek Casey
range is a 1.5m machine priced at €2,000. At the other end of the scale is the 4.5m machine which doubles up to a more manageable 3m during road travel. This costs €5,500.
Additional attachments can spec the machine as required. One common attachment that Bridgeway supply is the electronically driven seeder, often used for over seeding clover. This adds €1,000 onto the price. Another attachment is the scarifier.
This is simply a harrow-like implement that follows the aerator to clean out any dead grass in the sward. Again, this adds €1,000 onto the price.
Whatever size machine you use, the advice from experts is that you shouldn’t be travelling faster than 4-5kph when aerating ground. This is the speed at which the tines get maximum effect. With a 3m machine travelling at 5kph a farmer will cover about five acres an hour.
Another machine that has just hit the market is the AerWay Aerator. Imported here by Meath-based Farmec Ireland, this aerator is manufactured in Canada and features special tines that gently lift and fracture tough compacted soils to increase air and water movement (see picture).
These machines are available as either linkage mounted or trailed models with a range of working widths and prices start at €6,350 plus VAT.
The blades are angled so that when they are in the ground they open up the surface somewhat to allow the soil receive vital moisture and air with minimum surface disturbance.
NEVER TRY TO SUBSOIL YOUR WAY OUT OF TROUBLE WITH A BIG, HEAVY TRACTOR