Increasing the amount of available feed for winter is possible but it requires planning. In the case of nitrogen use, best results occur some 20 to 25 days after application. But, as usual conditions apply.
This note is to prompt some thoughts around a feed wedge and the when, where and how much, so planning can begin.
If the pastures are growing then a response to nitrogen is likely. However the extra dry matter produced depends on the time of application, amount of nitrogen, soil and pasture composition.
Once the decision has been made that a feed wedge over some of the property is required the key trigger point is soil temperature.
Best responses occur before the surface soil (0-10 cm) drops below 7 degrees C. Soil temperatures below about 4 degrees C produce little responses to applied N. So, going into the winter period and given feed will be utilized in about 20 to 30 days after application, start when soil temperatures are around 10 degrees. The soil temperature can quite rapidly drop below 7 in the early winter period.
Soils low in phosphorus and potassium will also reduce the likely response.
Finally, in this note about planning, it’s the grasses that are the target for the nitrogen application.
Annual, short rotation and perennial ryegrasses generally give better more consistent responses than other grasses. The more dominant the grasses the better and the amount of nitrogen applied will have little effect on the total production from sub clovers.
The next two articles discuss further the amount and response.
Article by Peter Flavel, Agronomy Advisor Meridian Agriculture
M: 0427 755 507 E: firstname.lastname@example.org
Article Series – Nitrogen on Pastures Check List
This is the first article in a series of three with a focus on Nitrogen on Pastures. See below for links to the other two articles in the series: