Estimating Food on Offer (FOO) is one technique for determining stocking rate. It is important that FOO is estimated at key times of the season, namely the start and end of the main growing season.

FOO estimates should also be made at times of the year when stock numbers can be adjusted as part of routine management such as shearing, crutching or pregnancy scanning when there is the chance to reduce or increase stock numbers, based on the assessment of feed availability.

It should be noted that effective rainfall can sometimes fall outside the normal growing season. The effectiveness of the rain will depend on the amount, the temperature when the rain falls and the type of vegetation that occurs where the rain fell – perennials are more likely to respond to small and infrequent rainfall events.

When undertaking FOO estimates, the following points should be considered:

• The grazing radius of stock; sheep will not graze much beyond 3 km from water in the summer. Cattle will not graze beyond 5 km in the summer. Salty water or salty feed will reduce the grazing radius. In good seasons when surface water is present, the grazing radius will expand.
• Estimates should incorporate different land systems or significant changes in feed types or quantities
• Sites where FOO is estimated can be formalized using GPS coordinates and site photographs. This information can be incorporated into a paddock book of historic FOO estimates
• The palatability and quality (digestibility) of the feed that is available; if palatability of a large proportion of the pasture is low, this should be considered when undertaking the visual estimate. However, keep in mind that only a proportion of the FOO will be utilised.

Use the following tools to refine your skills in this area.