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A pasture feed wedge is a tool that visually displays your farm's current pasture situation. By ranking your paddocks based on average pasture cover, it can help you make proactive decisions about pasture management. This page describes how to plot a feed wedge weekly for high pasture utilisation. It can help you quantify average pasture cover, identify targets, spot surpluses and deficits early, decide the grazing order for next week, and make timely decisions. The page also explains how to calculate pre-grazing cover targets and post-grazing residual targets, and provides useful visual examples. It's an essential tool for efficient and stress-free pasture management.
A pasture feed wedge gives a visual picture of the current pasture situation by ranking the paddocks based on average pasture cover. By adding a target line, it becomes a simple but effective tool to make pro-active decisions.
As farms become larger and systems more varied, the challenge is to make pasture management decisions easier, accurate, and less stressful. The answer for many farms will be the implementation and use of the pasture feed wedge.
Plotting a feed wedge weekly is essential if you want to achieve high pasture utilisation on your farm.
A feed wedge is most useful when the round length is not changing i.e. from balance date through to the autumn. At other times of the season when rotation length is changing, the feed wedge is best used with other pasture management tools.
A feed wedge is a graph of paddock covers (kg DM/ha) (y axis) and paddock descriptors (x axis) for a dairy farm for a selected day, sorted by paddock from longest to shortest pasture cover.
The line drawn on the graph from longest to shortest paddocks, along with the graph axes resembles a wedge shape, hence the name.
If target pre- and post-grazing covers are placed on the graph at the highest and lowest paddock covers and connected by a target line, it is easy to see which paddocks have a surplus or deficit of pasture.
There are two ways the pre-grazing cover can be calculated:
(Stocking rate x Intake1/ x Rotation) + Optimum residual = Pre-grazing cover
(___ cows/ha x ___ kgDM/cow x ___days) + _____kg DM/ha = _____ kgDM/ha
E.g. (3.0 cows/ha x 18 kg DM/cow x 22 days) + 1500 kg DM/ha = 2700 kg DM/ha
(Cows x Intake1/) / Area offered + Optimum residual = Pre-grazing cover
( ____ cows x ____ kgDM/cow) / (___Effective area ÷ ___rotation length) + ____kg DM/ha = _____ kgDM/ha
E.g. (300 cows x 18 kg DM/cow) / (100 ha ÷ 22 days) + 1500 kg DM/ha
= (5400 kg DM ÷ 4.54 ha/day) + 1500 kg DM/ha = 2700 kg DM/ha
Note: 1/ Intake is pasture only
The post grazing residual needs to be a consistent, even height throughout the milking season. This height is relatively consistent throughout the season at around 8 clicks using the Rising Plate Meter (i.e. 1500-1650 kg DM/ha using the formula “clicks” x 140 + 500).
Once the cover is assessed in each paddock, the paddocks can be ranked from longest to shortest in a table. This can be done manually using a pen and paper or using computer software providers.
For a list of programs that offer feed wedges see the Pasture assessment page.