Grassland management concerns the production and utilisation of grass. In the UK the formal management of grassland can be traced back to the Stone Age, over 5000 years ago as farmers sought to convert grass into useful products, for example milk and meat. We consider lowland grassland management in the context of today's agriculture:

Amongst the many different types of grass that are found throughout the UK, all share a common characteristic in their the seasonality of growth. Grass hardly grows at all when the temperature is below 5°C, but grows vigorously in the warm wet conditions that are typical of the April, May and June period.

The productive capacity of grassland depends on a large number of factors but in the main is dependant upon the climate and the soil. Mild temperate weather with deep rich soils being the most favourable. Other factors such as the topography of the land, species mix, and sward damage can be important, but generally to a lesser extent.

Grass, like all other crops, responds to soil conditions that are high in fertility. This may be naturally occuring, for example in the deep soils in alluvial flood plains, or it can be artificially enhanced by the application of fertiliser. The principal nutrients that grasslands require are nitrogen (N), phosphorous (P), potash (K) and sulphur (S) where the (letter) symbolises the appropriate element. Farmers can apply fertiliser in either organic, or inorganic form, depending upon its availablity and suitability*.

The challenge for all farmers in grassland management is to exploit the potential of grass growth in the early summer period by growing lots of it, but in such a manner that it is utilised without waste. This necessitates part of the grassland area being allocated for the production of silage or hay for use as a winter fodder.

Surplus grass growth in relation to livestock requirements is illustrated in the graph alongside. In the spring farmers may be reserving as much as 2/3 of their grassland acreage for the production of silage or hay. By mid summer this may have fallen to 1/3 with the entire grassland acreage being grazed by late summer.

However, grassland management is about more than just production. Farmers need to provide their livestock with grass or conserved grass (silage and hay) that is of the right palatability and nutritional quality. In this respect livestock have very differing requirements. Dairy cows need lots of young nutritious grass or silage to support milk production whereas beef cattle do best on grass that is more mature and of lower palatability.

Sheep require swards where the grass length is short and will not utilise grassland efficiently if the grass is more than a few inches tall. The effective management and utilisation of grassland therefore often involves different livestock grazing the same grassland in a complimentary manner.

* The case of sulphur is interesting - sulphur used to be discharged into the atmosphere in large quantities by power stations, a process that gave rise to acid rain. Although acid rain was detrimental to some ecosystems it nonetheless provided necessary sulphur to grassland and arable crops. With the advent of much cleaner burning technology and a move towards "cleaner fuels" (gas instead of coal), the amount of sulphur in the atmosphere has greatly reduced and grass can become deficient without additional application by the farmer.

User comments - post a comment