An Introduction to Pastures in Australia

Hi :) This post will introduce you to pastures and their use in Australia. We'll discuss what makes pastures important and also have a look at how pastures have changed in Australia since European settlement as well as how and where pastures are used for animal production.

Before we begin, let's go over some terminology which is certainly worth knowing. Firstly, the definition of 'pasture' is "a population of herbaceous ('non-woody') plants with a relatively short growth habit and continuous ground cover." This includes grasses, legumes and herbs and may grow in tropical or temperate climates. Pastures can be annual, that is they produce seed and then die, or perennial, they are alive continuously. A 'grassland' is land on which the vegetation is dominated by herbaceous plants with little woody vegetation. These can be found in regions of Africa, China and Mongolia. A 'rangeland' is land on which the indigenous or native vegetation is predominantly shrubs, grasses and forbs and which are managed more extensively. 'Forage' refers to the edible part of plants that provide feed for animals or can be harvested for feeding to animals. 

The Importance of Pastures 

The characteristics of pastures influence what animals eat and how fast they grow. High quality pasture provides an animal with more food to eat. The more food available, the more the animal will eat and the more they eat, the more they grow. This allows the farmer to earn more money because the animal will produce more milk, wool, meat etc. Grasslands and rangelands are important because they occupy about half of the world's land area and are mostly used for the production of livestock and wild herbivores. In addition, the demand for food is expected to more than double in the near future as the world's population continues to increase. Pastures help people produce food. Meat production world wide has increased dramatically in recent years and this has been termed the "Livestock Revolution". Meat production requires good pasture. 

The Change in Pastures Since European Settlement in Australia 

After the European settlers arrived in Australian in 1788 there was a massive replacement of natural vegetation (this includes trees, shrubs and native grasses) on 25 million hectares with sown pastures in southern Australia. From about the years 1800 to 1900 the sheep and cattle industries were quite large and there were massive changes in grasslands due to grazing and the clearing of native vegetation. Various annual grasses and forbs were also introduced to Australia during this time. The years 1900 to 1950 saw the beginning of agricultural research which brought improvements such as sub-clover and superphosphate. These resulted in a significant increase in production. The 'ley-farming' system also began being used during this time and trace element deficiencies in soils were discovered. However, war, depression, rabbits and drought brought about massive land degradation and these new practises weren't used. 

Between 1950 and 1970 saw the rapid expansion of pasture in Australia. Myxomatosis eliminated the rabbits and there was a wool boom. In addition, the government provided tax concessions for pasture improvement and there was greater access to more pastures that were adapted to Australian conditions. Further declines in native grassland were experienced. The 70's saw multiple droughts as well as new diseases, insects and pests. Increased soil acidification and salinity as well as more intensive cropping also occurred. Farmers were put under economical strain too and so there was less money to buy fertiliser. 

The period of time between the 80s and now can be described as the 'restoration' phase of development. This is because of the land care and sustainability movement and the fact the people began tackling soil erosion, acidification, compaction and salinisation problems. There is now a greater focus on the use of perennial pastures and a greater range of more locally adapted legumes are used.

Where and How Pastures Are Used in Australia

Several environmental factors influence the growth and persistence of pastures, these factors include:

• The amount and distribution of rainfall
• Seasonal temperatures
• Solar radiation

Different pastures have different levels of adaptation to the factors that influence growth.

Where Pastures are Used in Australia
Source

 We've been asked to focus on remembering the zones that are in the southern half of Australia only. It is also important to note that these pasture types aren't delineated by soil type. Instead, other factors (such as location, topography, rainfall amount and distribution, and how easy it is to clear vegetation) determine how land is used.

 Australian farming systems currently use pastures is several ways:

• As Permanent Pastures: this is when land is continuously used to grow pasture. This is usually done on land that is difficult to crop.
• Ley Farming: this is when the farmer alternates between growing pasture and a crop on the land. ie on year 1 pasture will be grown, on year 2 a crop will be grown, on year 3 pasture will be grown and so on. 
• Phase Farming

That's it for this post, if you have any questions don't hesitate to ask :)