Reproduction without fertilisation usually by the asexual production of seeds (agamospermy) (as in e.g. Citrus Sorbus). Includes vegetative reproduction (stolons rhizomes suckers etc.) (as in e.g. Ulmus).
The exposed tip of a seed scale in a mature closed conifer cone. Particularly significant in the genusPinus.
Lying flat against an object.
(after name(s) of the author(s) of a plant name) Literally ‘in the writings of’. Usually used where the name was published by one author or authors in the work of another.
A non-native plant introduced to an area in ancient times (pre-1500 AD in the United Kingdom).
Fleshy outgrowth produced at the base of a seed (as in e.g. Taxus). Often acts to attract animal seed-dispersal agents.
The author(s) of a plant name. The names of these authors are stated directly after the plant name often abbreviated. For example Quercus L. (L. = Carl Linnaeus); Rhus wallichii Hook. f. (Hook. f. = Joseph Hooker filius i.e. son of William Hooker). Standard reference for the abbreviations: Brummitt & Powell (1992).
State of increased ploidy resulting from doubling of the normal two sets of chromosomes in a single species.
Angle between the upper side of a leaf and the stem.
(in female cones of Pinaceae) Papery structures that subtend the seed scales. Derived from modified leaves and may be included (e.g. Tsuga) or exserted (e.g. Pseudotsuga). In other conifer families bract scale and seed scale are fused.
Small branch or twig usually less than a year old.
Immature shoot protected by scales that develops into leaves and/or flowers.
Reduced scale-like leaf partially enclosing a bud.
Puckered; with blister-like swellings on the surface.
Roots produced from the stem above ground that gradually fuse with the main stem providing additional mechanical support. buttressed (of stem) With buttress roots.
Falling off early.
Relating to lime- or chalk-rich soils or water.
(of a plant) Growing on soil containing lime.
(of a plant) Avoiding soil containing lime (i.e. usually growing on acidic soil).
Cap-like structure that covers some flowers. Derived from fused-together petals and/or sepals. In Eucalyptus for example flowers may have either a single calyptra (sepals and petals) or an inner one (petals) and an outer (sepals).
Female reproductive organ of a flower. Composed of ovarystyle and stigma. Typically several carpels are fused together in each flower (syncarpous). The number of them can be of taxonomic significance; it can often be assessed by counting the stigma branches or the chambers in the fruit.
Firm and tough but flexible; gristly.
A reduced leaf. In Pinus cataphylls are scale-like non-photosynthetic leaves that line the stem.
With a long tail-like appendage.
Production of flowers directly on the trunk and stems (as in e.g. Cercis) rather than at stem apex.
Convention on Biological Diversity.
Dense vegetation consisting of low scrubby trees and shrubs often with small leaves and spines.
Fringed with long hairs.
Convention on International Trade in Endangered Species of Wild Fauna and Flora.
Made up or consisting of two or more similar parts (e.g. a compound leaf is a leaf with several leaflets).
Having the same colour throughout.
(of leaves) Folded once lengthwise.
Term used here primarily to indicate the seed-bearing (female) structure of a conifer (‘conifer’ = ‘cone-producer’); otherwise known as a strobilus. A number of flowering plants produce cone-like seed-bearing structures including Betulaceae and Casuarinaceae.
A scale in a cone. In Pinaceae this term generally refers to the seed scale while in other conifer families it refers to the combined complex of bract and seed scale.
IUCN Red List conservation category: ‘facing an extremely high risk of extinction in the wild’.
Somewhat hard elastic; resembling a hard crust or shell.
(cv., cvs) Cultivated variety; cultivated plant selected for feature(s) that is/are useful and/or appealing to growers that is clearly distinct uniform and stable in its characteristics and remains so when propagated. A cultivar is indicated by single quotation marks around the name (e.g. Quercus rysophylla ‘Maya’). For the rules on naming a cultivar see the International Code of Nomenclature for Cultivated Plants.
Resembling the growth of an Equisetum (horsetail).
(appearing before the author(s) of a plant name) Indicates the author who published the plant name validly. For example Quercus floribunda Lindl. ex A. Camus: ‘ex’ denotes that the latter author (Aimée Camus) published the name validly; the name had been used previously by the former author (John Lindley) but had not been validly published by him.
Protruding; pushed out.
IUCN Red List conservation category: ‘there is no reasonable doubt that the last individual [of taxon] has died’.
Extinct in Wild
IUCN Red List conservation category: ‘known only to survive in cultivation in captivity or as a naturalised population (or populations) well outside the past range’.
Outside the flower. Used to describe nectaries situated on vegetative parts of a plant.
A first-generation hybrid between two individuals.
The second generation of progeny from an original hybridisation event; derivatives from the generation.
In the Cupressaceae the scale leaves are arranged in alternating pairs (see decussate). The pair comprising the upper and lower leaves are the facial pair. (Cf. lateral pair.)
A group of genera more closely related to each other than to genera in other families. Names of families are identified by the suffix ‘-aceae’ (e.g. Myrtaceae) with a few traditional exceptions (e.g. Leguminosae).
Grey-blue often from superficial layer of wax (bloom).
globularSpherical or globe-shaped.
(or cultivar group) Collective name for a number of cultivars within a genus or species with similar characteristics. A very useful modern concept enabling the naming of many similar plants without the need to provide a cultivar name for each: so for seed-raised plants that come nearly true from seed (as e.g. Quercus texana New Madrid Group); or for the progeny of a repeatable hybridisation; or for variants of a species that cannot be maintained as distinct entities by taxonomists but have horticultural merit and need to be distinguished. ‘Group’ is always included in the name. Named cultivars may be selected from within a cultivar group.
Bare seeds protruding from the cone in Juniperus due to insect damage.
Specimen or illustration chosen to serve as the type specimen for a taxon in cases where one was not designated by the original author.
Two-valved fruit formed from a single carpel widely known as a ‘pod’ typical of most members of the legume family (Leguminosae). The word has come to be used as much for members of the family as for their distinctive fruits.
Pore on the stem. lenticellate Bearing lenticels.
Woody climber growing from ground into canopy.
Woody tuber developed in the axils of the cotyledons or the first few leaf pairs. Common in Eucalyptus where they provide a means for regeneration after a fire.
Division of a leaf or other object. lobed Bearing lobes.
(of a group of taxa) With a single ancestor; part of a natural lineage believed to reflect evolutionary relationships accurately (n. monophyly). (Cf. paraphylypolyphyly.)
With simple stem/axis extending by growth of the apical bud and bearing lateral branches. (Cf. sympodial.)
With a single seed. Many junipers in Juniperus section Sabina produce monoseed cones.
(of a genus) Including only one species (as e.g. Aextoxicon).
The visible form of an organism.
From the measurement of shape.
Short straight point. mucronate Bearing a mucro.
Novel characteristic arisen as a result of a spontaneous genetic change mutant Individual with a mutation.
(pl. mycorrhizae) Beneficial fungus associated with the roots of a plant. Different forms of association occur (e.g. arbuscular ectendo- endomycorrhizae) depending on how the fungus and the plant roots interact.
Pollinated without control. Where plants are open pollinated unexpected hybrids may occur.
Lowest part of the carpel containing the ovules; later developing into the fruit.
Egg-shaped; broadest towards the stem.
Structure inside ovary that when fertilised becomes a seed.
Vegetation above the treeline in tropical South America mostly grasslands and scrub.
Roughly hand-shaped; (of a leaf) divided partially or fully to the base with all the leaflets arising from the tip of the petiole (as in e.g. Aesculus).
A much-branched inflorescence. paniculate Having the form of a panicle.
Small protuberances on surface of petal or leaf sometimes hair-like in appearance. papillose Bearing papillae.
(of a taxon usually at generic or family level) With a common ancestor but some of the other descendants of that ancestor are excluded from the taxon for subjective reasons of the taxonomist (n. paraphyly). Such a classification is therefore not ‘natural’. (Cf. monophyly, polyphyly.)
(of a taxon) Including entities descended from different ancestors and evolutionary lineages grouped usually as a result of superficial similarities (n. polyphyly). The grouping is therefore not ‘natural’. (Cf. monophylyparaphyly.)
Fleshy fruit with leathery core. Typical of Rosaceae subfamily Maloideae (e.g. Malus).
(pl. stomata) Small pores on the leaves (and young stems) that allow for gas exchange.
An epiphytic vine or tree whose roots extend down the trunk of a supporting tree and coalesce around it eventually strangling it.
(horticultural) Expose seeds to cold weather to promote germination.
Bearing fine longitudinal stripes grooves or ridges.
Bearing stiff hairs or bristles.
Cone. Used here to indicate male pollen-producing structure in conifers which may or may not be cone-shaped.
Generally an elongated structure arising from the ovary bearing the stigma at its tip.
Persistent remains of the style at tip of an acorn.
(prefixed to tech. term) Beneath; less than; approximately.
(subsp.) Taxonomic rank for a group of organisms showing the principal characters of a species but with significant definable morphological differentiation. A subspecies occurs in populations that can occupy a distinct geographical range or habitat.
(of two organisms) Dissimilar but closely associated living together in a mutually beneficial manner.
With the same distribution as another taxon (or with overlapping distribution). (Cf. allopatric.)
With stem/axis terminating (perhaps after the production of a flower) and growth continuing via lateral branches. (Cf. monopodial.)
Flower in which the carpels are fused together to form a single unit. (Cf. apocarpous.)
(syn.) (botanical) An alternative or former name for a taxon usually considered to be invalid (often given in brackets). Synonyms arise when a taxon has been described more than once (the prior name usually being the one accepted as correct) or if an article of the International Code of Botanical Nomenclature has been contravened requiring the publishing of a new name. Developments in taxonomic thought may be reflected in an increasing list of synonyms as generic or specific concepts change over time.
Region of sparse coniferous forest in northern latitudes.
Traditional English name for the formerly independent state known to its people as Bod now the Tibet (Xizang) Autonomous Region of the People’s Republic of China. The name Xizang is used in lists of Chinese provinces.
Dense layer of soft hairs. tomentose With tomentum.
Defined in USDA Plant Hardiness Zone Map which divides the North American continent into ten zones each representing an area of winter hardiness for plants based on average annual minimum temperatures.
United States National Arboretum.
(of similar parts of a plant: e.g. petals) Meeting without overlapping; (of dehiscent fruit) opening via valves.
(var.) Taxonomic rank (varietas) grouping variants of a species with relatively minor differentiation in a few characters but occurring as recognisable populations. Often loosely used for rare minor variants more usefully ranked as forms.
Pattern of veins (nerves) especially in a leaf.
The priming of a plant response (e.g. germination flowering) by exposure to low temperatures in winter.