Management of Grass Reseeds

Reseeding grassland is an expensive operation and ensuring that the new seedlings establish into a strong and vibrant sward is essential. Michael Gottstein and Philip Creighton, Teagasc Sheep outline some key steps that need to be taken in order to maximise the performance of the reseed.

Reseeding grassland is an expensive operation and ensuring that the new seedlings establish into a strong and vibrant sward is essential if the exercise is to be a success. As these newly reseeded swards head into the winter there are a number of key the steps that need to be taken to maximise the performance of the reseed over the winter and into next year.

Weed control

For most reseeds the post emergence sprays will have already taken place at this stage. Late sown reseeds (Mid-August) are due their post emergence spray now. This is a very important task that should under no circumstances be omitted. Certain weed species can grow at lower temperatures than grass and these will colonise the sward over the winter period resulting in a poor and weedy grass sward next spring if the post emergence spray is not carried out.

Lime

In most situations Lime will have been applied at sowing time. If ground limestone was spread at the required amount (as per soil samples) then the pH should be ok for the next few years. If bagged granular lime has was used then it is probably not a bad idea to follow up with an application of ground limestone (according to soil sample recommendations) when ground conditions allow. Ground limestone is much cheaper and in general a single application will correct the pH over a 3 – 5 year period.

N, P & K

The window for spreading chemical Nitrogen and Phosphorous has closed so where reseeds are growing on low fertility soils and need extra nutrients to bring them up to target soil fertility consider applying Farm Yard Manure or slurry if available and ground conditions are suitable for spreading without causing damage.

Grazing  

The biggest aid to tillering and good establishment for a newly reseeded sward is regular, tight grazing. Sheep farmers have an advantage here as sheep are the ideal animal to graze out reseeds without causing any soil damage particularly when weather conditions are sub optimal. On cattle farms, calves or lighter cattle can be used to do this job. It is essential that the swards are grazed regularly (every 4weeks) at lower covers 7-8cm (1000-1200kg DM/ha) and that  before being closed for the winter the sward is grazed out fully (down to 4cm) to allow light down to the base of the sward to encourage tillering.

Summary

Protect your investment, give the new reseed the best chance to come through the winter by 1) controlling weeds, 2) Looking after PK & Lime requirements and 3) Grazing out the sward to 4cm before closing for the winter. Your reward will be a well established and productive sward for many years.