Abiotic influence

Influence exerted by non-living organisms, i.e. by factors such as climate and chemical and physical properties of the soil. Decomposition products from previously living organisms can be of critical importance.

Absorption

Uptake

Adsorption

Attachment to a surface.

Adventitious plant

Species that has been introduced accidentally but does not yet have the ability to spread significantly, e.g. from ports and warehouse areas. Often temporary.

Adventitious shoot/bud

Shoot/bud formed from previously dormant tissue, often after external influence, e.g. cutting, pruning of older shoots. Adventivus (Latin) means something that breaks through.

Annual

One-year plant that can flower and set seed in the same year.

Apomictic

Plant that can produce seeds without fertilisation.

Apophyte

"Original plant" - species that has expanded its habitat due to activities in human cultivation, e.g. mowing, grazing (cf. synanthrope).

Archeosynanthrope

Plant introduced directly or indirectly by humans in the past.

Aromatic

Perfumed or fragranced.

Autecology

Study of the interactions between an individual species and its surroundings.

Biennial

Two-year plant. During the first year it forms a rosette. In the following year it develops a shoot that can flower and set seed and then normally die entirely.

Biomass

Mass of mainly living plant material (expressed as fresh weight or dry weight).

Biotope

Habitat for a particular group of plants, animals and other organisms (cf. growing site).

Biotype

Individuals with a genetic composition that gives them similar appearance and behaviour.

C3-plants

See C4-plants.

C4-plants

Plants where the base molecule in the photosynthetic reaction contains 4 carbon (C) atoms instead of the 3 in C3-plants. C4 plants have an optimum temperature for growth that is approx 10 degrees higher than for C3-plants and cope with drought better. Therefore C4-plants have an advantage over C3-plants in a warm, dry climate. Examples of C4-plants are millet, amaranth and petty spurge. In the Nordic climate such species many occur in open, poorly competitive crops.

Capsule

A dry fruit formed from two of more united carpels and dehiscing when ripe (usually by splitting into pieces or opening at summit by teeth or pores).

Chamaephyte

Plant that bears hibernating buds on persistent shoots near the ground.

Chinampa

Cultivation method used before Spanish colonisation in ancient Mexico. Small, rectangle-shaped areas (< 3000 m=) were created in wetlands. The soil was taken from canal excavations and bottom sediment, which were held in place by stockades. To maintain the very high soil fertility, nutrient-rich sediment material and organic mulch was added continually. The crops grown were maize, squash, amaranth, chilli, beans and flower. The latter were used for various Aztec ceremonies to worship the gods

Ciliated

Edge lined with hairs.

Cleistogamous

Having flowers which self-pollinate and never open fully or self-pollinate before opening.

Clone

A plant derived from the vegetative reproduction of a parent plant, with both plants having identical genetic constitutions.

Cryptogams

A collective term for the "lower plants" which produce spores and do not have stamens, ovaries or seeds; literally plants whose sexual reproductive organs are not conspicuous. Typically includes the ferns, bryophytes and algae, and sometimes fungi (including lichenized fungi).

Dicotyledon

Plant with two cotyledons.

Diversity

Range or variety of species

Ecological amplitude

Refers to the amount of variation in a certain factor, e.g. light, temperature, moisture, an organism (e.g. a plant) can tolerate for survival (opposite to physiological amplitude).

Ecology

From the Greek oikos house, home, and -logia science, study (compare economy = "husbandry"). The area of biology that refers to the interaction between an organism, e.g. a plant, and the environment in which it lives.

Ecosystem

A limited part (large or small) of nature that we have decided for some reason to study as a whole. Consists of a living component (biotic) and a non-living component (abiotic) that is found within the system.

Ecotype

Modification of a species as a result of site influences on the genetic characteristics.

Endemic

Species only present in a limited area where it is ínativeí.

Endozooic spread

Spread of seeds through being eaten by animals, particularly birds, and passing through the digestive tract.

Epidermis

Protective surface layer of cells on a plant.

Epizootic spread

Spread of seeds by animals or humans through attachment to e.g. fur or clothing.

Evolution

Development / change in organisms to altered characteristics and adaptation (often to a higher, more specialised type).

Facultative

Voluntary, optional. Opposite to obligate.

Fitness

Measure of the reproductive ability or growth rate of a certain genotype (degree of adaptation to the particular habitat).

Flora

The plants occurring within an area or a period of time.

Generalist

Species that can live in a broad spectrum of environments.

Generative phase

Stage from development of flower buds through flowering and seed formation until the seeds or fruit fall from the tree.

Genetic variation

Variation due to gene mutation or recombination of genetic material

Genotype

An individualís inherited genetic characteristics (intrinsic).

Geophyte

Plant with its overwintering shoot tips under the soil surface, e.g. bulb and tuber plants.

Gland

Small group of cells releasing or containing oil, resin, etc.

Glandular hair

Hair that exudes or contains oils, resins, etc.

GMO

Genetically modified organism.

Grass

Monocotyledonous species belonging to the family Poaceae

Green biomass

Undried plant material.

Green manure

Manuring through ploughing in a soil-improving crop (green manure crop).

Hair

One or multi-celled protrusion from the epidermis (outer surface tissue of the plant).

Hapaxanth

Plant that flowers and produces seed only once and then dies.

Hay

Dried, storable material of grassland plants for feed.

Hemerophile

Plant that is benefited in some way by cultivation practices.

Hemerophobe

Plant that is directly hampered by cultivation practices.

Hemicryptophyte

Plant with shoot tips overwintering near the soil surface, e.g. most flowering plants and grasses.

Herbicide

Chemical weed control agent (Latin herba = plant and -cid = killer).

Horticulture

Garden science.

Humus

Organic material (e.g. detritus) that has undergone various stages of decomposition, the last stage being humus.

Hybrid

Cross between two species.

Hypocotyl

Part of the stem under the cotyledons, transitions into root.

Intermediary

Intervening form.

Internode

Piece of stem between two nodes in plants where these are clearly apparent, e.g. grass and young shoots in several other plants.

Interspecific relationship

Relationship between species.

Intraspecific relationship

Relationship within species.

Invasive species

Species that spreads and can establish in areas outside its original habitat and e.g. threaten biological diversity and human health and cause economic damage.

Mat-forming plant

Species that forms a dense, low growing mat of vegetation from runners.

Mecophile

Plant species that spreads its seeds with the help of animals, e.g. greater celandine, cleavers.

Monocotyledon

Plant with one cotyledon.

Monoculture

Cultivation of a single plant species (crop) on a field.

Morphology

Science of an organismís external appearance.

Mould (soil)

See humus.

Mutation

A natural, unpredictable change in genetic material that brings about an alteration in the characteristics of a plant or other organism. The alteration is often negative, leading to difficulties in survival. However it can sometimes lead to better adaptation and survival capacity.

Mycorrhiza

Means ífungus rootí. Refers to interaction between fungus and plant roots that is of benefit to both organisms.

Naturalised

Plant that has established itself and can reproduce in a new area for that species.

Nectar

Sweet liquid produced by glands that attracts insects to the flower.

Neophyte

Newcomer plant that spontaneously spreads in its new area, e.g. bindweed.

Neosynanthrope

Plant species directly or indirectly introduced by man relatively recently, e.g. pineapple weed, false oatgrass, dwarf snapdragon.

Node (leaf knot)

Point of leaf attachment on a stem or straw.

Obligate

A compulsory behaviour or method of existence. An obligate parasite is an organism that can only live parasitically. European dodder is an obligate parasite on another plant. Opposite facultative.

Plant cuticle

A protecting film covering the epidermis of leaves, young shoots and other aerial plant organs without periderm.

spp.

An abbreviation of species (plural), often used to collectively refer to more than one species of the same genus, as in "Astragalus spp"

Spur

A conical or tubular outgrowth from the base of a perianth segment, often containing nectar.

Thorn

A sharp, stiff point, usually a modified stem, that cannot be detached without tearing the subtending tissue; a spine. Compare prickle.

Viviparous

The development of plantlets on non-floral organs, e.g. leaves.