This glossary explains botanical and related terminology that you may come across in wildflower books and in plant science papers.
Term | Explanation |
---|---|
Achene | One-seeded, non-splitting dry fruit |
Acidophile | Preferring to grow on acid soils |
Achlorophyllose | Without chlorophyll, a green pigment, and therefore unable to photosynthesise |
Actinomorphic | Radially symmetrical or having more than one plane of symmetry |
Aculeate | Armed with sharp prickles or thorns |
Acute | Sharply pointed (referring to a leaf, for example) |
Adventitious | Roots and buds that appear on a stem in abnormal places |
Albinism | A complete lack of pigmentation |
Albino | Plant lacking pigmentation |
Alien | Plant introduced from outside its natural range |
Alkaline | Calcareous or chalky substrates |
Allele | One possible form of a gene |
Allogamy | Fertilisation by pollen from a flower of the same species |
Allopatric | Species in geographical areas that do not overlap |
Alternate | Leaves occurring singly on opposite sides of a stem, rather than in pairs |
Anemophilous | Pollinated by wind |
Angiosperm | Flowering plant whose seeds develop inside an ovary |
Annual | A plant that germinates, flowers and dies within 12 months |
Annular | Ring-shaped |
Anther | A male reproductive organ of a flower that bears pollen |
Anthocynanins | Pigments producing red or purple colours |
Anthoxanthins | Yellow pigments in plants |
Aphyllous | Without leaves |
Apical | At the tip |
Apochromy | Having abnormal colour |
Apomixis | Seed reproduction from unfertilised egg cells |
Aquatic | A plant whose natural habitat is water (usually implying inland freshwater habitats) |
Asymbiotic | When symbiotic fungi are absent |
Auricles | Ear-shaped structures |
Autogamous | Self-pollinating |
Axil | The angle between a stem and a branch or a leaf |
Back-cross | Cross between a hybrid and one of its parents |
Basal | Located at the base of an organ, for example a leaf at the base of a stem |
Bog | Wet, acidic peat |
Bosses | Irregular swellings |
Bract | Leaf-like structure often found beneath a flower |
Bracteole | Secondary bract at the base of secondary branches of the flower stalk |
Bulb | Food storage organ formed by a cluster of fleshy leaf bases |
Bulbil | A small bulb sometimes located in the axil of a leaf or bract |
Calcareous | Usually refers to limstone rock or chalky soil with a high calcium content |
Calyx | The outer whorl of a flower, which is made up of its set of sepals |
Capsule | A dry seed pod |
Carapace | Hardened shell |
Carpel | The female seed-producing unit in a flower, consisting of an ovary connected by a style to a stigma |
Cilia | Tiny fleshy hair-like structures |
Chlorophyll | Green pigment important in photosynthesis |
Cladode | Modified stem that resembles a leaf (for example in Butcher's Broom) |
Cleistogamous | Self-pollinating flowers with petals and sepals that never open |
Clone | Identical genetic match to a 'parent' |
Corolla | Inner whorl of petals of a flower |
Corona | Petal-like flaps, often elongated to form a crown-like tube (as for example in a daffodil) |
Crenate | Structures with minute scalloped or round-toothed margins |
Cross-pollination | Pollination of one flower by pollen from another, usually from a different plant |
Cyme | Cluster of flowers with lateral branches each ending in a flower |
Deciduous | Sheds leaves or other organs in one limited period during every year (unlike evergreens whose leaves are not all shed at the same time) |
Decurved | Curved downwards |
Deflexed | Bent sharply downwards |
Diploid | Normal state for plant cells - containing two matching sets of chromosomes |
Disc floret | A flower in the centre of a flower-head whose petals form a tube |
Drupe | Fleshy fruit containing seeds surrounded by a toughened coat (as in plums, peaches etc) |
Drupelet | One of a group of connected drupes (as in blackberries etc) |
Ectomychorrhiza | Association with fungi where the fungus forms a layer on the outside of the roots of a plant |
Endomychorrhiza | Association with fungi where the fungus penetrates the root of a plant |
Epicalyx | Second ring of sepal-like organs immediately below the true sepals (calyx) |
Epichile | Outer portion of the lip in those orchid genera where the lip is divided into two parts |
Epidermis | A 'skin' or surface layer |
Epiphyte | A plant that grows on the surface of another but without taking nutrients from it |
Escape | Refers to a non-native plant that is cultivated and then becomes established in the wild |
Esker | Glacial deposits such as sand and gravel |
Eutrophication | Where a habitat becomes over-enriched with nutrients. This happens frequently with rivers or ponds as a result of run-off from farming and is often the cause of native species becoming stifled or destroyed |
Fall petal | One of the three outer petals of the iris that droop downwards |
Family | Classification unit grouping closely related genera |
Fen | Marshes and wetlands sited on alkaline, neutral or only very slightly acid soil, often but not always beside lakes |
Floret | One of the small flowers contained in a flower-head |
Filiform | Thread-like |
Flower head | A cluster of florets or flowers |
Garrigue/Garigue | Habitat with low-growing shrubs with wide gaps in between them. Common in the Mediterranean region |
Geitonogamy | Fertilised by pollen from a flower on the same plant |
Genus | Classification unit grouping together closely related species (Pl. genera) |
Gland | Superficial organ that secretes oils or other substances |
Glandular hair | Hair containing a gland |
Hemiparasitic | A plant relying partly on the nutrients abstracted from other plants |
Herbarium | Collection of dried, pressed plants |
Herbaceous | A plant that dies down to ground level at the end of the growing season |
Hooded | Developed into a concave shape |
Hybrid | Plant originating from cross pollination between two different species |
Hybrid swarm | Population of plants where the barriers between two species have broken down leading to hybrids and back crosses interbreeding. The resulting plants exhibit a variety of characteristics from both 'parents' |
Hybrid vigour | Where plants of the first generation of hybrids become exceptionally large and robust |
Hypanthial tube | Tube formed from by an extension of the receptacle below a flower |
Hyperchromic | Having an excessive amount of pigmentation, resulting in more intense colour |
Hypha | Fine thread-like structure that makes up the body of a fungus. Pl. hyphae |
Inflorescence | A group of flowers arising from one stem |
Intergeneric hybrid | A hybrid where the 'parents' are from two different genera |
Internode | Stem section between two nodes |
Introduced | Brought into an area by human or other means |
Involucre | Ring of crowded bracts encircling a flower head |
Involucral bract | Bract forming part of an involucre |
Keel/Keel petal | Lower fused petals of a pea flower folded to form a hull-like structure |
Lanceolate | Oval and narrowing to a pointed tip |
Latex | Milky sap |
Lax | Loose rather than densely packed (usually applied to the flowers in an inflorescence) |
Lignify | To become woody |
Lip | A petal that protrudes, forming a lobe. Found in orchids and in flowers of the Mint family |
Machair | Confined to the coasts of western Ireland and Scotland, a sandy, lime-rich (usually as the result of crushed shells) habitat usually species-rich |
Maquis | An area of densely-packed shrubs up to five metres in height. Common in the Mediterranean region |
Meadow | Grassy field which kept for the production of hay and grazed only infrequently |
Mealy | A flour-like texture or substance |
Mericarp | One-seeded portion of a fruit formed when it splits from the rest of the fruit |
Monocarpic | Flowers once and then dies |
Mutualism | Relationship between organisms from which all benefit |
Micorrhizome | Early stage of seedling development during which it is solely dependent on fungi for nutrients |
Mycorrhiza | Relationship between plant and fungus where the fungus will penetrate or form a layer over the roots |
Mycelium | Mass of branching filaments that make up the body of a fungus |
Mycotrophic | Acquiring nutrients from fungus |
Native | Belonging to a region through natural circumstances |
Naturalised | Introduced to a region but subsequently forming self-sustaining populations |
Nectary | Nectar-secreting gland |
Node | Point on a stem where one or more leaves are attached |
Ovary | Female reproductive organ containing ovules |
Ovule | Organ inside ovary enclosing the embryo sac containing an egg |
Panicle | Branched cluster of flowers with stalks |
Pappus | Tuft of hair on achenes or other fruits which aids seed dispersal |
Parasitic | Entirely dependent for it survival on abstracting nutrients from another plant |
Pasture | Grassland that is grazed for part of a year and not cut for hay or silage |
Pedicel | Stalk of flower |
Petals | Inner whorl of perianth segments - the outer one being the sepals |
pH | Measure of acidity or alkalinity based on a logarithmic scale of hydrogen ion concentration, where 0 is most acidic, 7 is neatral, and 14 is most basic (alkaline) |
Pheromone | Chemical produced by animal or insect that influences the behaviour of other members of the same species |
Photosynthesis | Process of production of food by green plants |
Phototropic | Acquisition of food by photosynthesis |
Pinnate | Leaflets arranged on two sides of a single stalk |
Pollen | Spores with single cell containing male gamete |
Pollinium | Mass of pollen transported during pollination |
Raceme | Unbranched flower cluster where each flower is stalked |
Ray/Ray-floret | Outer, flattened flower of a daisy-type flower head with a large petal extending radially outwards; the inside reagion of the flower head consists of disc florets with much smaller, equal-sized petals |
Receptacle | That part of the stem that has flower parts attached to it |
Recurved | Bent or curved backwards |
Reflexed | Bent down or back |
Reticulation | Marked with network of veins |
Rhizome | Creeping (usually underground) thickened stem that stores food |
Runner | Stem that creeps along the ground and forms roots at periodic intervals that will eventually form separate plants |
Saprophyte | Plant feeding on rotten vegetation in the ground |
Scape | Leafless stem bearing flowers |
Secund | Facing in the same direction |
Sepal | Outer row or ring of perianth segments forming the protective covering of a flower bud |
Septum | A thin partition or membrane separating the individual seeds within a seed pod or fruit |
Sessile | Without a stem |
Silicula | Fruit of the cabbage family, often rounded and three times longer than it is broad |
Simple | Leaves not divided into leaflets |
Spadix | Fleshy spike with unstalked flowers |
Spathe | Large hooded bract enclosing a spadix |
Species | Classification of a group of similar individuals that breed true in the wild |
Speculum | Mirror-like patch found on the petals of some orchids |
Spike | Unbranched cluster of flowers that are unstalked |
Stamen | Male reproductive organ of a flower |
Spur | Hollow pouch, sometimes cylindrical or conical, projecting from a flower and containing nectar |
Standard/Standard petal | Upright, upper petal of a pea flower that is larger than the others |
Stemless | A plant without an obvious stem but with a flower stalk that arising directly from the ground |
Stigma | Part of a flower that receives pollen |
Stigma ray | Star-shaped stigma with radiating branches |
Stipule | Leaf-like organ at the base of a leaf stalk |
Stolon | Stem growing horizontally above or below the ground |
Style | The part of the female reproductive organ that joins the ovary to the stigma |
Subshrub | Small perennial with woody stems |
Succulent | Plant with fleshy leaves |
Suture | Seam along which pods or other fruits split open |
Symbiosis | Relationship between two or more organisms in which all benefit |
Tap root | Strong main root that grows vertically downwards |
Tepal | Petals and sepals that cannot be clearly distinguished from each other |
Trifoliate | Leaf made up from three distinct leaflets, for example as in clover |
Tuber | Food storage organ formed by a swollen underground stem |
Tubercle | Small warty protuberance |
Umbel | Flat or domed-topped flower cluster with all the stems originating at the same place, as for example in cow parsley |
Valve | One of several parts of a fruit that become partially or fully separated |
Whorl | Collection of organs that encircle a stem |
Wing/Wing petal | Lateral petals of many flowers particularly orchids and pea flowers |