My colleague Brian Costello finished the last weeks update with the suggestion that once the “South Westerly’s” are back rain will not be far behind, and given the recent dry spell, be prepared for the growth surge. Well it has come to pass. As I write in North Cork, the rain is teaming down. A few quick phone calls to clients in the East and West reports that the same is happening there – so for a change, the expectations for increased growth rate should be echoed across the country.
In the past week recorded growth rates ranged from 45-59 kgDM/ha/day – well below the expected average for May of 70-80 kgDM/ha/day. The reason for this is quite clear and is due to the lack of moisture. Nitrogen response, especially to Urea has consequently been low. Examination of most grass wedges in the past week show that there is a clear step – with paddocks to be grazed up to or above the target line and those grazed in the past 10 days well below the target line. Paddocks with a good cover of grass are less likely to “dry out” and will continue to grow on. Paddock grazed are the opposite and re-growth suffers.
These steps or dips in the wedge has had concerned many farmers over grass supply for the next 10-14 days, but now for many there may be a quick turn around from deficit to surplus. A farm walk is an absolute must within the next 4-5 days to gauge the increase in growth. It is most likely that demand must be increased to control this increase in growth. In most cases this involves “skipping over” high cover paddocks (>1600-1700 kgDM/ha) and closing ground for silage. Remember not to set demand too high – try to keep it below 70 kgDM/ha/day until first cut aftergrass comes back into the platform. If you continue to grow a surplus above this demand, then skip the paddock and bale/wagon it ASAP. Many farms have bred their bulling heifers on the milking platform, temporarily increasing demand, and once AI’d or bulled, are removed again – this is decreasing demand so be sure to account for this.
Reseeded paddocks will also get a lease of life after today’s rain. Fertiliser application on these reseeds should have been delayed until there was reasonable green cover on the paddock – otherwise there may be nitrogen losses due to volatilisation. When cover reaches circa 200+ kgDM/ha/day – be prepared to apply nitrogen to help it along. If grass supply is adequate on the farm, be also prepared to apply the first grazing to these reseeds when the cover is circa 500 kgDM/ha/day (be mindful of root pull) – and graze it to <3.5cm – the cows will do it for pleasure!. Each subsequent grazing should be at covers of <1000 kgDM/ha, on a short rotation if necessary, to prevent shading at the base to guarantee a good graze out. Your management in the first year of a reseed is critical to ensure a long life for that reseed – do the simple things – graze at light covers, graze to <3.5cm, no poaching, fertilise to realise its potential.
