Managing damaged swards as a result of a tough spring
This spring created many challenges on farms as a result of tough weather conditions. The challenges experienced included fodder shortages, reductions in protein and butterfat in milk due to a high volume of grass silage in the diet, and damage to grazing paddocks. Soil temperatures are improving this week and grass growth is picking up.
Unfortunately, especially in the west of the country ground conditions still remain challenging but hopefully these will improve soon. This spring highlighted the importance of grazing infrastructure on farms to aid in the management of on/off grazing to promote grass utilisation while minimising damage to the sward. These measures are been excellently illustrated at a number of recent Grass10 farm walks hosted by the national, regional and category winners at the moment.
However, even on farms where excellent infrastructure was already in place, damage has been caused to the ground and grazing swards. The challenge for the next rotations will be to maintain grass growth rates and quality, and also to rectify the damage in these swards and ensure that the rest of the grazing season will not be affected.
The issues that may arise as a result of damage caused by grazing include slower regrowth and the potential to have increased weed populations on damaged swards. Weed infestations may occur from weed seed being allowed an opportunity to germinate as a result of poaching, and increased establishment in patches left bare by weak grass tillering.
The measures that can be taken to improve the recovery of damaged ground include the application of P fertiliser. Phosphorus is critical to root development and stimulation. Where large amounts of slurry have already been applied an NP fertiliser would be the most suitable. If sulphur has yet to be applied then consider an NP+S as the responses to earlier sulphur have been increasingly common as a result of improved air quality. Nutrigrass P (20-4.4-0-7.2) may be a suitable product. The inclusion of TOP-PHOS P will aid in the repairing of damage experienced in grazed swards while allowing for increase of the P concentration in herbage close to breeding. The N component of this fertiliser is a protected phased release N and will reduce concerns over early N which may be carried over from the first and/or second round of fertiliser.
If weed populations do arise on farms then there are a number of options. Control of weed establishment can be achieved by spraying paddocks using a selective herbicide. While recent selective herbicides have been designed to minimise checking of grass, they do not eliminate it. With this in mind, many will be wary to spray weeds this spring as not to inhibit grass growth and build covers and silage reserves. Farmers around the country have been overcoming this issue of grass check by using a product called Fertileader Stimgrass. Stimgrass is a plant biostimulant that can be applied along with your selected herbicide. The Fertileader Stimgrass is designed to reduce the stress of the herbicide application experienced by grass and create an increase in plant activity to utilise fertiliser applied and increase grass protein levels and reduce free nitrogen in the grass.