WACE ATAR Agricultural Science and Technology key terms

The combined way a farm uses land, water, labour, machinery and livestock to produce output. It includes inputs, processes and outputs and how these interact with the surrounding environment.

The combination of separate production activities, such as wheat, canola, sheep or dairy, run on one property. The mix spreads risk, uses labour and land efficiently and shapes the farm's overall income.

Setting goals and allocating land, capital and labour across the entire property over several years. It balances production, profit, risk and natural resource care rather than optimising a single paddock.

A rating of how well a parcel of land can support a particular use without being degraded. It considers slope, soil depth, erosion risk and climate and guides which enterprises are suitable.

The detachment and movement of topsoil by wind or water. It removes nutrients and organic matter, reduces productivity and can pollute waterways, so it is managed through ground cover and contour works.

The proportion of the soil surface protected by living plants, stubble or litter. High cover cushions raindrops, slows runoff, reduces wind erosion and conserves moisture for the next crop.

The accumulation of salt in surface soil where a rising watertable brings dissolved salts upward. It occurs after deep-rooted vegetation is cleared and reduces crop and pasture growth.

The upper level of saturated soil or rock below the ground surface. Where it rises close to the surface, waterlogging and salinity can develop and root growth is restricted.

A pasture based on plants that live for several years, such as lucerne or kikuyu. Deep roots dry out the soil profile, reduce recharge and provide feed through more of the year.

Leaving crop residue on the paddock after harvest instead of burning or baling it. It protects soil, stores moisture and adds organic carbon, but can host pests and tie up nitrogen.

The movement of nutrients such as nitrogen, phosphorus and potassium between soil, plants, animals and residue. Managing the cycle reduces fertiliser reliance and losses to waterways.

The downward movement of dissolved nutrients or salts through the soil profile with drainage water. It can remove valuable nitrogen from the root zone or move salt into groundwater.

The timing of a plant's growth stages, such as emergence, flowering and grain fill. Matching a variety's phenology to local frost and heat patterns is central to crop management.

The cold period some cereals and canola need before they can flower. Varieties differ in how much cold they require, which determines where and when they can be sown safely.

A measure of accumulated heat above a base temperature that drives crop development. It helps growers predict maturity and compare seasons more reliably than calendar days alone.

The range of dates in which a crop can be sown to balance yield potential against frost and heat risk. It depends on variety maturity, soil moisture and expected rainfall.

The area of green leaf above each unit area of ground. It indicates how much light the canopy can intercept, and too little or too much both reduce crop yield.

The above-ground arrangement of leaves and stems in a crop or pasture. Its size and structure determine light capture, airflow, disease risk and how evenly sprays reach the target.

The amount of dry matter a crop produces per unit of solar energy it intercepts. It links canopy size and health to biomass and helps explain differences in yield.

A strategy that combines monitoring, biological control, resistant varieties, cultural practices and targeted chemicals to keep pests below damaging levels. It reduces reliance on sprays and slows resistance.

The pest population level at which the cost of control equals the value of the crop loss avoided. Spraying above this level is justified; below it, treatment usually wastes money.

The inherited ability of a pest population to survive a pesticide dose that once killed it. It develops under repeated selection pressure and is managed by rotating chemical groups and using non-chemical tactics.

Body weight raised to the power 0.75, used to compare energy needs of animals of different sizes. It reflects that larger animals need less feed per kilogram of body weight.

The weight of feed an animal eats after accounting for its moisture content. It sets the ceiling on nutrient supply and depends on body weight, feed quality and stage of production.

The proportion of feed nutrients an animal absorbs rather than excreting in dung. High digestibility means more energy and protein are available for growth, milk or reproduction.

The kilograms of feed needed to produce one kilogram of liveweight gain, milk or eggs. A lower ratio means more efficient conversion and directly affects enterprise profitability.

A standardised rating of an animal's fat and muscle cover, usually assessed by hand over the spine and hips. It guides feeding decisions and predicts reproductive performance.

The period when rams, bulls or boars run with females for mating. Its timing is planned so lambing, calving or farrowing coincides with the best feed supply and weather.

Removing young animals from their mothers' milk so they eat solid feed. Timing affects growth, stress and the mother's recovery, and influences the next joining date.

Managing within-paddock variability using GPS guidance, yield maps, remote sensing and variable-rate application. It targets inputs where they are needed, cutting waste and improving yields.

Equipment that changes the rate of seed, fertiliser or spray across a paddock according to a prescription map. It matches inputs to soil and crop variation and reduces over-application.

A spatial record of crop yield collected by a harvester during harvest. It reveals patterns of poor and good performance that guide soil testing and variable-rate decisions.

Collecting information about land or crops from satellites, aircraft or drones without contact. Vegetation indices help monitor growth, moisture stress and disease across large areas quickly.

A ratio calculated from red and near-infrared reflectance that indicates how green and vigorous vegetation is. It is used to map crop biomass, stress and variability.

The amount of grain, pasture or livestock product produced per unit of water used. Raising it means more output from the same rainfall or irrigation, which improves both profit and sustainability.

An instrument placed in the soil that measures water content at one or more depths. Readings show when the root zone is drying and support timely, evidence-based irrigation decisions.

Deciding when and how much to irrigate using soil moisture, evapotranspiration and crop demand. Good scheduling avoids waterlogging and deep drainage while meeting crop needs.

Enterprise income minus variable costs, expressed per hectare or per head. It compares the profitability of alternative activities without including fixed overheads.

The yield needed for an enterprise's income to cover its costs. Comparing it with expected yield shows how much margin of safety a decision has.

The uncertainty of output and input prices between planning and sale. It is managed through forward contracts, futures, storage decisions and spreading sales over time.

Using futures, options or contracts to lock in a price and offset the risk of adverse market moves. It protects a budget but may forgo gains if prices later rise.

An agreement to sell a specified quantity and quality of produce at a set price on a future date. It secures income but carries delivery and production risk.

The sequence of steps that turns farm inputs into a product reaching the consumer, including production, processing, transport and retail. Understanding it helps farmers capture more value.

The quality, size, safety and presentation standards a buyer requires for produce. Meeting them determines whether a product can be sold and at what price.