GRASSLAND MANAGEMENT

Grassland Management

Grassland Management

Introduction

The EU environmental (e.g. Habitat directive) and rural development policies aim to integrate nature and landscape conservation values in agricultural land. Baldock introduced the concept of High Nature Value farmland (HNV), including "hot spots" of biodiversity in rural areas, usually characterised by extensive farming practice (EEA, 2004). In 2003, European Ministries of Environment agreed to identify all farmland areas with high natural value and to take conservation measures (UN/ECE, 2003). Even if a definitive map of EU HNV still does not exist, preliminary studies show that in Sardinia such areas cover roughly 50% of Utilized Agricultural Area, mostly represented by grazed grasslands and rangelands (AAVV PSR, 2007). The Island is considered an important centre of plant biodiversity. Its flora includes 2400 entities, 5% of which are endemics (Arrigoni, 2006). Mediterranean agro-pastoral systems based on grasslands, mostly managed as pasture and rarely as meadow, are most included in HNV farmland, where plant biodiversity emerge from the interaction between ecological factors and agro-pastoral management. Grazing activities have been associated to the sustenance of biodiversity in different ecosystems, as they are compatible with the maintenance and conservation of a diversity of habitats with high species richness and endemicity (Verdù et al., 2000). However, the natural and agronomic values of grassland vegetation may change in relation to grazing species, stocking rate and grassland management, generating serious environmental issues from both abandonment and overgrazing.

Categories of Grassland

There are three main categories of grassland.

a. Rough Mountain and Hill Grazing:

More appropriately called grazing than grassland as most of the land is taken up with heather, gorse, bracken and scrub rather than grasses.

It is characterised by large range in composition, low stocking rates and low production.

The land is usually acidic or peaty and generally stony.

It can therefore be very difficult or impossible to cultivate.

b. Permanent Grassland

This is grassland that is never ploughed.

It is different from Hill Grazing because it is dominated by perennial grasses and scrub, and trees are rare.

It again displays a large range in botanical composition from highly productive grasses to clover to highly unproductive weeds.

Generally permanent grassland is more productive than mountain and hill grazing areas and is also more highly stocked.

c. Leys

These are short term areas of grassland, sown by the farmers which display the following characteristics:

Little variability in botanical composition

High stocking rates

High levels of production.

Leys are associated with good farm practices and high levels of management and are resown and reseeded regularly.

Grassland Distribution

Grass dominates most of the land in nearly all the counties in Ireland.

In Munster, Ulster and Connaght it can be up to 90% of all agricultural land.

In the south - east it is only about 75%. Why?

The following table shows the relative amounts of grassland in Ireland.

Grassland Ecology

The natural vegetation in Ireland is deciduous forest.

This basically means that if all agricultural and industrial activity stopped, the land would eventually return to ...