Grassland Part 1

 Categories of grassland found in Ireland.  Grass species found in these grasslands.  Grassland Ecology.

 Grassland occupies 70% of the world’s agricultural land, making it the world’s most important crop.  In Ireland, grass provides 70 – 80% of our cattle’s feed requirements and over 90% of our sheep’s.  Approximately 90% of the farmed land area in the country is devoted to grassland and is the primary resource for almost all of our agricultural output.

 There are three main categories of grassland. 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.

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.

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 re-sown and re-seeded regularly.

 Grass dominates most of the land in nearly all the counties in Ireland.  In Munster, Ulster and Connacht 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.

Category of Grassland Area (Ha, millions) % of Agricultural Land Mountain / Hill Grazing Permanent Grassland Leys

 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 forest.  The stages of progression are as follows:  Bare Soil  Grasses  Shrubs (Bramble, hawthorn and Blackthorn)  Forest species like Oak, Ash, Birch and other trees which eliminate shrubs by their shading effect.

 Intensive grazing prevents this series of activities to take place.  This is because grass species can regenerate from points below the grazing level.  If grazing was reduced or stopped, shrubs would take over and then eventually trees.  This is important as the farmer must manage his / her grassland so as to ensure that unwanted shrubs don’t take over the area.