ABSTRACT
I. INTRODUCTION Agriculture is an important industry for Australia. In 2000, some 23 million hectares were under cultivation (ABS, 2002). Beef and wheat are the most important agricultural commodities, each producing over US$2.5 billion per annum. Wheat utilizes the largest area of land of any crop (over 12 million hectares) (ABS, 2002). Various other grain crops are grown, including barley and canola, often in rotations with wheat. Rice is also grown, sometimes in conjunction with wheat.
