NCEA L1 Ag & Hort key terms

The process where green plants use sunlight energy to combine carbon dioxide and water into sugars, releasing oxygen. It supplies the energy that feeds nearly every agricultural and horticultural system.

The breakdown of sugars inside living cells to release usable energy, using oxygen and giving off carbon dioxide and water. It happens day and night and uses up some of what photosynthesis produces.

The green pigment in leaves that absorbs light energy for photosynthesis. Its amount and health strongly affect how fast a plant can grow and how much dry matter it makes.

The loss of water vapour from small pores in leaves, mainly through the stomata. It pulls water and dissolved nutrients up from the roots and cools the plant on hot days.

Tiny openings, mostly on the underside of leaves, that let carbon dioxide in and water vapour and oxygen out. Guard cells open and close them in response to light and water stress.

The tube-like tissue that carries water and dissolved minerals upward from roots to stems and leaves. Its flow is driven largely by water loss through transpiration in the leaves.

The living tissue that moves sugars made in leaves to other parts of the plant, such as roots, fruit and growing tips. It carries the products of photosynthesis to where they are needed.

A mineral element a plant needs in relatively large amounts, such as nitrogen, phosphorus, potassium, calcium, magnesium and sulfur. Shortages of any of these limit growth and reduce yields.

A major nutrient needed for proteins, chlorophyll and leafy growth. Plants short of it look pale and grow slowly, while too much can make soft growth and delay flowering or fruiting.

A nutrient important for root development, energy transfer and flowering or fruiting. It moves little in soil, so placement near the roots matters more than for many other nutrients.

A nutrient that helps regulate water movement and supports strong stems, fruit quality and disease resistance. Crops harvested for fruit or tubers usually remove large amounts of it.

A material added to soil or plants to supply nutrients. It may be organic, such as compost or manure, or manufactured, and is described by the ratio of nitrogen, phosphorus and potassium it contains.

A laboratory or field measurement of soil properties such as pH and available nutrients. Results guide how much lime or fertiliser to apply so inputs match what the crop needs.

A scale from 0 to 14 measuring how acidic or alkaline a soil or solution is. Most crops grow best between about 5.5 and 7, where nutrients are most available.

Ground limestone or similar material spread on soil to raise pH and reduce acidity. It also supplies calcium, and applying it changes how readily other nutrients become available.

The downward movement of dissolved nutrients, especially nitrate, through soil and out of the root zone with drainage water. It wastes fertiliser and can pollute groundwater and streams.

Water that flows across the soil surface instead of soaking in, carrying soil particles, nutrients and animal waste with it. It causes erosion and can contaminate waterways.

The wearing away and removal of topsoil by water, wind or cultivation. Because topsoil holds most nutrients and organic matter, losing it steadily reduces the land's productive capacity.

The uppermost layer of soil, usually darker and richer in organic matter and roots than the layers beneath. It is the main zone where crops obtain water and nutrients.

Dead plant and animal material in soil at various stages of decay. It improves structure, holds water and nutrients, and feeds the soil organisms that release nutrients.

The way soil particles clump together into crumbs and pores. Good structure allows air and water to move freely, supports root growth and resists compaction and erosion.

The squeezing together of soil particles so that pore space is reduced. It restricts root growth and water drainage, and is often caused by heavy machinery or stock on wet ground.

The removal of excess water from soil through pores, drains or ditches. Poor drainage waterlogs roots, reducing oxygen supply and slowing growth for most crop plants.

Decomposed organic material made from plant and kitchen waste under controlled conditions. It is added to soil to improve structure, water holding and nutrient supply rather than to give a quick nutrient boost.

A layer of material spread on the soil surface, such as straw, bark or plastic. It reduces evaporation, suppresses weeds and moderates soil temperature around crop plants.

Growing different crop types in a planned sequence on the same land over successive seasons. It helps break pest and disease cycles and balances nutrient use and soil condition.

A plant family, including clovers, peas and beans, that forms partnerships with bacteria in root nodules to convert atmospheric nitrogen into a form plants can use. They enrich soil nitrogen.

Leaving land uncropped for a period, often to allow moisture and nutrients to build up or to reduce pest and disease carryover. It may be managed with cover plants or cultivation.

A plant grown mainly to protect and improve soil rather than for harvest. It reduces erosion and leaching, adds organic matter and can suppress weeds between main crops.

The amount of usable product harvested from a given area of land, such as kilograms per hectare or tonnes per hectare. It is the main measure of how productive a crop or system is.

The portion of a plant or feed left after all water is removed, expressed as a percentage or weight. It allows fair comparison of feed value and of pasture growth between samples.

The energy in a feed that an animal can actually digest and use for maintenance, growth or milk production. It is a key figure when comparing feeds or planning rations.

Land covered with grasses and clovers grazed by livestock. Its growth, quality and persistence depend on species choice, grazing management, fertility and moisture.

Allowing livestock to eat pasture or forage directly from the land. Timing and intensity of grazing control how well plants recover and how much feed regrows.

The number of animals carried on a given area of land, often expressed as stock units per hectare. Matching it to pasture growth prevents overgrazing or wasted feed.

A standard measure of animal feed demand, based on a mature ewe grazing about one kilogram of dry matter per day. It allows different classes of stock to be compared and added up.

Damage to soil and pasture caused by hooves pressing into wet ground. It pugs the surface, buries grass and creates bare patches where weeds can establish.

An organism that damages crops, pasture or stored produce, such as insects, mites, slugs or birds. Control combines monitoring, cultural methods, biological agents and chemicals where needed.

An abnormal condition of a plant or animal caused by a pathogen such as a fungus, bacterium or virus. It usually spreads through spores, contact, vectors or contaminated soil and equipment.

Using a living organism, such as a predator, parasite or pathogen, to reduce a pest population. It can be long-lasting but needs careful selection so the control agent harms only the target.

A combined approach that uses monitoring, cultural, biological and chemical methods, with pesticides as a last resort. It aims to keep pests below damaging levels while limiting costs and environmental harm.

A substance used to kill or control pests, including insects, weeds and fungi. Correct choice, dose and timing matter to be effective and to avoid harm to beneficial organisms and waterways.

A plant growing where it is not wanted, competing with crops for light, water and nutrients. Weeds can also harbour pests and diseases and reduce harvest quality.

The inherited ability of a pest, weed or disease organism to survive a control method that would normally kill it. It develops faster when the same chemical is used repeatedly.

Official restrictions on moving plants, animals or produce to stop pests and diseases reaching new areas. Border inspection and certification are part of this system.

The practices and rules that prevent pests and diseases entering a farm, region or country and spreading. It includes hygiene, movement control, monitoring and quick reporting of unusual problems.

A planted margin of vegetation alongside a stream or drain. It traps soil and nutrients from runoff, stabilises banks and shades water, improving waterway health.

Managing land so it stays productive over the long term without depleting soil, water or biodiversity or causing unacceptable off-site effects. It balances economic, environmental and social outcomes.

The transfer of pollen from the male part of a flower to the female part, allowing seed and fruit to form. Wind, insects and other animals can all act as pollinators.

The joining of male and female reproductive cells after pollination to form a seed. In crops grown for fruit or grain, it is essential for setting a harvestable yield.

The starting of growth from a seed, requiring water uptake, suitable temperature and usually oxygen. It ends when the young root emerges through the seed coat.

A resting state in which seeds or buds will not grow even if conditions seem suitable. It prevents growth at the wrong time and often needs chilling, light or time to break.

The structure formed after fertilisation that contains an embryo, stored food and a protective coat. It is the main way most crop plants are established and spread.

Cutting away parts of a plant to shape it, control size, remove dead wood or improve light penetration and fruiting. The timing and type of cut affect regrowth and yield.

The arrangement of leaves and branches that intercept sunlight. Its size, density and shape determine how much light a crop captures and how well air moves through it.

Growing one crop species over a large area or in repeated seasons. It simplifies management but can build up pests and diseases and increase reliance on inputs.

The amount of feed an animal needs to produce a unit of growth, milk or eggs. A lower value means the animal is turning feed into product more efficiently.

The physical and mental wellbeing of animals under human care, covering food, water, shelter, health, comfort and natural behaviour. It is both an ethical and a production concern.

Waste water and manure from animal housing or yards. It is a valuable nutrient source if spread at the right rate and time, but a serious pollutant if it reaches waterways.