For most of the Waikato this has been a very mild winter and spring and while it definitely became wetter in August, many areas are still relatively dry. This has meant not only consistently higher pasture growth but also less pasture damage and consequently more of the farm actually producing pasture. The result is many farms are carrying higher covers than normal for the time of year and pasture management decisions are being made 10-20 days earlier than usual.
Consequently we are in the unusual position of having to control post grazing residuals that may have been left too high in the last grazing, or in many cases the current round length is a lot longer than usual to make the cows graze to close to target residuals. In both of these situations cows are potentially eating poorer quality pasture heading into mating, either because the pasture is too long or the residuals been eaten into are low quality, and maintaining a longer round is simply perpetuating this.
The two major management strategies are speeding up the round by harvesting surplus as silage or dropping paddocks out for cropping and/or topping.
- Dropping paddocks out for silage - visit http://bit.ly/DairyNZ_PastureSurplus a DairyNZ info sheet on Surplus Management, including how to calculate what area to take as surplus. However if by the time this article is published you are one of the farms that still finds itself with 200-400kgDM/ha cover more than target and “trapped” on a longer round, then removing silage for control will be based on getting back to entry covers needed at the area you want to feed, as well as anticipated growth and surplus in the future.
- Topping - Often when paddocks can’t be removed for silage (for example you already have enough area out of the round) but were either left too long last grazing or will be too long this grazing, then topping in front of the cows to the required residual is a good option. This can be done as full paddocks or “half a paddock” each grazing if you wish to minimise the risk of growth slowing.
The essential point here is that you want residuals at 1500-1600kgDM/ha for best quality re-growth.
For information regarding monitoring nutrition during mating read Katrina Robert’s article from October 2018 here: