NCEA Level 2 Agricultural and Horticultural Science key terms

The amount of usable product harvested from a crop or animal system, usually measured per unit area or per animal, such as tonnes per hectare or kilograms of milk solids.

The rate at which a farming system produces output relative to the resources used, such as output per hectare, per animal, or per unit of labour and input.

How well a system converts inputs such as feed, water, fertiliser or labour into outputs. Higher efficiency means more product gained for each unit of input used.

The number of animals grazed on a given area of land, commonly expressed as stock units per hectare, which affects pasture use, feed supply and environmental impact.

A standard measure of feed demand, where one stock unit represents the feed needed by a mature ewe of about 55 kg producing one lamb. Used to compare different classes of stock.

The maximum number of animals or level of production an area of land can support sustainably without degrading soil, pasture or other resources over the long term.

Managing a farming or horticultural system so it meets present production needs while maintaining soil, water, biodiversity and economic viability for future generations.

Land covered with grasses and legumes managed for grazing livestock. Its quality and composition depend on species, fertiliser, grazing pressure and climate.

The portion of feed or plant material remaining after all water is removed. It is used to compare feed value and pasture mass because water content varies widely.

The energy in feed that an animal can actually digest and use for maintenance, growth, reproduction or milk production, usually expressed in megajoules per kilogram of dry matter.

The amount of feed an animal consumes to gain one unit of body weight or produce one unit of product. A lower ratio indicates more efficient conversion of feed.

Controlling when, where and how long livestock graze pasture, including rotation length and residual pasture levels, to balance pasture regrowth with animal feed demand.

A plant family, including clovers and lucerne, that forms nodules with nitrogen-fixing bacteria and adds nitrogen to the soil, improving pasture and crop nutrition.

The process by which certain bacteria, often living in legume root nodules, convert atmospheric nitrogen gas into forms plants can use, reducing reliance on applied nitrogen fertiliser.

Growing different crops in sequence on the same land to manage soil nutrients, break pest and disease cycles, and improve soil structure rather than growing one crop repeatedly.

The arrangement of soil particles into aggregates and pore spaces. Good structure supports root growth, water infiltration, aeration and resistance to erosion and compaction.

The squeezing together of soil particles that reduces pore space, limiting water drainage, airflow and root penetration. Often caused by heavy machinery or grazing on wet soil.

The wearing away and movement of soil by wind or water. It removes fertile topsoil and is worsened by bare ground, steep slopes and poor soil structure.

The downward movement of dissolved nutrients, especially nitrate, through soil and into groundwater or waterways. It is increased by excess fertiliser and heavy rain on bare soil.

A material applied to soil or plants to supply essential nutrients such as nitrogen, phosphorus, potassium and sulphur. It may be manufactured or derived from organic sources.

A laboratory analysis of a soil sample that measures nutrient levels, pH and other properties, guiding how much fertiliser or lime a grower should apply.

A scale from 0 to 14 measuring how acidic or alkaline a soil or solution is. Soil pH strongly affects the availability of nutrients to plant roots.

A material, usually ground limestone, applied to soil to raise pH and reduce acidity, improving conditions for pasture and crop growth and nutrient availability.

A nutrient required by plants in relatively large amounts, such as nitrogen, phosphorus, potassium, calcium, magnesium and sulphur, needed for growth and yield.

A nutrient needed by plants in only small amounts, such as copper, zinc, boron, manganese and molybdenum, but essential for healthy growth and development.

The process by which green plants use sunlight, water and carbon dioxide to produce sugars and release oxygen, forming the basis of all crop and pasture growth.

The process in which plants and animals release energy by breaking down sugars using oxygen, producing carbon dioxide and water. In plants it continues day and night.

The loss of water vapour from plant leaves through small pores called stomata, drawing water and nutrients up from roots and cooling the plant.

Tiny pores on the surface of leaves that open and close to allow carbon dioxide in for photosynthesis and water vapour out during transpiration.

The artificial supply of water to crops or pasture when rainfall is insufficient, applied by methods such as sprinklers, drip lines or border dykes to support growth.

The ability of a soil to store water in its pore spaces and make it available to plant roots. It depends on soil texture, structure and organic matter.

Dead plant and animal material in various stages of decay within soil. It improves structure, water holding capacity and nutrient supply and supports soil organisms.

The dark, stable, fully decomposed portion of organic matter in soil that helps hold moisture and nutrients and improves overall soil structure and fertility.

The upper layer of leaves and stems of a crop or plant community. Canopy size and arrangement affect how much sunlight is intercepted for photosynthesis and yield.

Cutting back branches, shoots or roots of plants to shape growth, improve light penetration and airflow, control size, or remove damaged and diseased material.

The stage when dormant buds on a plant begin to swell and open, producing new shoots or flowers. Timing is influenced by temperature and winter chilling.

The amount of cold winter temperature a plant needs to break dormancy and resume normal growth, flowering and fruiting in the following season.

A resting state in which plant growth slows or stops, often during winter or drought, helping the plant survive unfavourable conditions until growth resumes.

The transfer of pollen from the male part of a flower to the female part, enabling fertilisation and seed or fruit development in crops.

In plant reproduction, the joining of male and female gametes after pollination to form a seed. In soil management, the term can also mean applying fertiliser.

The stage when flowers develop into young fruit after successful pollination and fertilisation. Poor fruit set reduces final yield in many horticultural crops.

An organism such as an insect, mite, slug or rodent that damages crops, pasture or stored produce, reducing yield, quality or market value.

An abnormal condition in a plant or animal caused by a pathogen such as a fungus, bacterium or virus, or by environmental factors, reducing health and productivity.

Using living organisms such as predators, parasites or pathogens to reduce pest populations, as an alternative or supplement to chemical pesticides.

A combined approach to controlling pests that uses monitoring, cultural practices, biological control and targeted chemicals, applying pesticides only when thresholds are reached.

The development of pest populations that survive a pesticide that once controlled them, often caused by repeated use of the same chemical and inherited tolerance.

Measures taken to prevent the introduction and spread of pests and diseases into a farm, region or country, protecting agriculture, the environment and trade.

Restrictions placed on the movement of plants, animals, soil or produce to stop the spread of pests and diseases, often enforced at borders or within a region.

Wastewater containing animal dung and urine, or other farm waste, that must be managed and applied to land carefully to avoid polluting waterways.

The physical and mental wellbeing of animals under human care, covering adequate feed, water, shelter, health, space and freedom to express normal behaviour.

The safe and low-stress movement and restraint of livestock using appropriate facilities and techniques, protecting both the animals and the people working with them.

The requirements a buyer sets for produce or livestock, such as weight range, grade, size or quality, which determine price and whether the product is accepted.

A planned system of checks and procedures that ensures farm or horticultural products consistently meet agreed standards for food safety, quality and traceability.