Protecting pasture in winter
Winter is the most vulnerable time for the health of farm soils and stock, and the impact of farming on water quality.
For example, there’s a greater risk of pastures becoming pugged from grazing and animal condition can drop due to the effects of wind, cold and wet conditions.
These sorts of problems can obviously hurt pasture growth and productivity.
Also, any grazing practices which lead to higher livestock densities during winter can cause a localised accumulation of waste more easily moved to surface water.
Such run-off, containing bacteria, nutrients and sediment, is exacerbated by cattle compacting wet soils.
So now’s a good time to reflect on how good stock wintering practices can help prevent problems or at least minimise them.
As a general rule, avoid feeding out supplementary feeds in areas where effluent run-off may reach any water body.
Feed pads and stand-off pads are options for protecting soil physical structure and animal condition over winter periods.
A feed pad is a dedicated concrete platform where supplementary feeds are brought to the stock.
It usually incorporates associated water troughs and must include effluent collection.
In this wintering option, higher feed efficiency is achieved as the waste is reduced to about 5 per cent compared to about 20 per cent or more when silage is fed in paddocks.
A stand-off pad is a dedicated, sealed loafing area for stock.
These pads are constructed using a softer, free-draining surface and use materials like wood chips over a sealed base.
As stock can be withheld from pasture for longer periods of time, the area required for each cow has to be bigger, say about eight square metres.
Effluent capture is an important aspect of stand-off pads.
They should incorporate a properly sealed base area where effluent can be collected for later use as free fertiliser.
Pads should always be away from waterways.
Also, when looking to build feed and stand-off pads, get good information about the characteristics of the farm’s soils, as this helps identify the specific risks associated with them (and whether a pad is in fact necessary).
Aside from pads, another system gaining popularity is the herd home.
These are a combination of a feeding platform, a stand-off facility and an animal shelter.
Sheltered feeding takes place over slatted concrete floors.
As the cows stand on the re-enforced slatted floors, their effluent drops through the slats and into a concrete lined bunker below.
Some farmers use sacrifice paddocks, when the options listed above aren’t available.
These are paddocks on which future production is sacrificed to protect other areas of the farm from stock damage when it is very wet.
Lost production on sacrifice paddocks can be expected for several years, depending on how intensively they have been used and how much damage is caused to the soil.
Waikato Regional Council does not recommend using sacrifice paddocks because of the heightened risks involved, such as any discharge of effluent or sediment from them into waterways.
While sacrifice paddocks themselves aren’t illegal, any unauthorised discharge from them to water is.
The other disadvantages of sacrifice paddocks also include the risk of soil structure damage and possible animal health problems such as lameness and mastitis.
If soil potassium levels become too great (potassium is excreted in urine) it can predispose the calving cow to metabolic problems.
The specifics of sacrifice paddocks aside, it is generally a good management practice under wet pasture conditions to keep cows on green feed for four to six hours and stand them off for 18 to 20 hours to avoid accumulation of effluent on wet soils.
Shelter is helpful in stand-off areas for reducing animal maintenance requirements, saving feed and reducing soil or paddock damage by cutting grazing time.
When it comes to stock health, having shelter in stand-off areas helps protect animals and reduces their maintenance requirements.