Grass reseed needed every 5-10 years
After a mini-drought, recent rain was welcome, bringing a big grass growth boost. Those taking second cut silage hope rain holds off for another while, albeit that some ground is still stressed, and grass is getting very wiry, and heading out early.
The increased growth should encourage farmers to start planning autumn reseeding. Depending on the method, you should be starting to work on the swards to be reseeded over the coming weeks.
Grassland management
Most beef producers rely on grazed grass and grass silage as their main forage sources. The quality and quantity of grass produced can be the biggest feed related influence on animal performance and overall farm profitability.
Most beef and dairy farms have a proportion of swards that don’t always grow enough grass, especially at both shoulders of the year.
This is quite often due to the absence of a sufficient population of perennial ryegrass in swards.
However, it may also be due to factors such as sward age, pasture management, poaching, weed population and soil fertility etc.
It is always obvious how much better recently reseeded paddocks grow compared to older swards.
Underperforming swards and damaged paddocks need reseeding to produce a high yield of grass. It is also quite obvious in periods of rapid growth which paddocks are not growing grass efficiently.
Pastures deteriorate over time, this is a natural process and cannot be avoided
Reseeding is not cheap, so it should only be done where significant financial benefits are to be gained.
Depending on methods and nutrient requirements, reseeding costs around €300 per acre.
Benefits of reseeding and positive economic returns have been well proven.
.Generally, grazing ground should be reseeded every 8-10 years and continuous silage ground every 5-7 years, particularly if two or more cuts are taken annually.
It has been said that if two cuts of silage are taken annually, only 35-40% of sown grass remains after five years.
Methods of reseeding
Some continue to reseed with the traditional ploughing method. Some use direct drilling and stitching-in. Topsoil depth, stone population and soil structure may determine the most appropriate method.
Regardless of the method, there are important things you need to get right. A firm seedbed is needed for establishment of the new sward, and getting the pH of the soil up to desirable levels is equally important.
Soil P & K levels also need to be acceptable, to aid establishment.
Grass seed mixture
The mix on a beef farm should be determined by how you intend to use the sward.
Is it going to be mainly for silage or for grazing?
What is your stocking rate? What kind of soils are being reseeded?
Heading date and diploid/tetraploid proportions need to be considered when deciding.
Including clover or not will depend on how much nitrogen you apply and what herbicides you use for weed control.
Successful reseeding steps
Choose a field that is low yielding, with a high proportion of weeds and with less than 65% perennial ryegrass.
Soil test the fields.
Spray the fields with glyphosate
Establish a fine, flat and firm seedbed
Apply fertiliser and lime as per your soil test result.
Sow grass seed at 12-14 kg/acre.
The seedbed should ideally be rolled to ensure moisture is retained and the seed makes good contact with the soil.
Weed control: it is important to hit weeds at an early stage for maximum control.
Pest control: monitor the new crop for slugs, leatherjackets, frit fly and rabbits.
New sward management
The first grazing is very important for sward establishment.
Graze well to encourage tillering and increase vigour.
