page_title: Glossary of botanical terms
section_title: F
hierarchical_section_title: Glossary of botanical terms / F
caption_attribution_description: English: Oldenburgia grandis This specimen was photographed in Kirstenbosch, near Cape Town. Until it is near its full size, the growing leaf is densely felted in white.
context_page_description: This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology.
context_section_description: F1 hybrid
  A single cross; a plant breeding term for the result of a repeatable cross between two pure bred lines.
  F2 hybrid
  A plant breeding term for the result of a plant arising from a cross between two F1 hybrids; may also refer to self-pollination in a population of F1 hybrids.
  fabiform
  Shaped like a kidney bean.
  facultative
  Of parasites, optional. Compare obligate.
  falcate
  Curved like the blade of a scythe.
  family
  A taxonomic group of one or more genera with features and/or ancestry in common; the term for the principal rank between order and genus.
  farina
  powdery, pale yellow crystalline secretion consisting of flavonoids in Primula and other species
  farinaceous
  Powderiness that is mealy
  fascicle
   A cluster, e.g. a tuft of leaves all arising from the same node.
  fasciculate
  Branching in clusters like a bundle of sticks or needles; having fascicles.
  faveolate
  Honeycombed; having regular, angled pits. Compare foveolate.
  faucal
  Pertaining to the fauces; located in the throat of a calyx or corolla.
  fauces
  The throat of a calyx or corolla; the conspicuously widened portion between the mouth and the apex of the tube. In Boraginaceae, the site of distinctive appendages.
  felted
  Covered with very dense, interlocked and matted hairs with the appearance or texture of felt or woollen cloth.
  female flower
  See pistillate flower.
  fenestrate
  Having translucent areas. See also perforate, with holes.
  ferruginous
  Ruddy or rust-colored.
  fertile
  Capable of producing fruit; of flowers when they produce seed or of anthers containing pollen.
  fertilization
  The union of male and female gametes during sexual reproduction.
  fiber
  1.  A fiber cell.
  2.  Any flexible, strong, stringy, and very elongate structure.
  fiber cell
  a type of cell that is found in sclerenchyma, it is much elongated and dies soon after an extensive modification of its cell wall. The cell wall is usually thickly lignified, but is sometimes gelatinous.
  filament
  1.  The stalk of a stamen.
  2.  Any very narrow, thread-like structure that is one or a few cells thick.
  filamentous
  consisting of filaments or fibres, hairlike.
  filiform
  thread-like. e.g. stamen filaments, or leaf shapes.
  fimbria
  slender hair-like process (plural: fimbriae)
  fimbriate
  Fringed.
  fissure
  A split or crack, often referring to fissured bark; a line or opening of dehiscence.
  fistule
  A tube-shaped cavity.
  fistulose
  Hollow; usually applied to a tube-shaped cavity, as in a reed.
  flabellate
  Fan-shaped.
  flaccid
  Limp; tending to wilt. Compare turgid.
  flexistyly
  Depending on the degree of maturation of the stamens, the style moves up or down (cataflexistyle or (ana-)hyperflexisyle).
  flexuous (flexuose)
  Bent alternately in different directions; zig-zag.
  floccose
  Having a soft and woolly covering of hairs.
  flora
  1.  all the plants growing in a certain region or country.
  2.  an enumeration of them, generally with a guide to their identification (e.g. the present volume, the Flora of Victoria, the Flora of New South Wales and so on). In this case 'flora' is written with a capital F.
  floral envelope
  See perianth.
  floral leaves
  The upper leaves at the base of the flowering branches.
  floral diagram
  A graphical means to describe flower structure, usually a schematic cross-section through a young flower.
  floral formula
  A description of flower structure using numbers, letters and various symbols.
  floral tube
  An imprecise term sometimes used as a synonym of hypanthium or of corolla tube or of calyx tube.
  floret
  A small flower, usually referring to the individual true flowers clustered within an inflorescence, particularly those of the grasses and the pseudanthia of daisies.
  flower
  The sexual reproductive structure of the angiosperms, typically with a gynoecium, androecium, perianth and an axis.
  foliate
  Preceded by a number: having a certain number of leaflets; for example, 3-foliate, "having three leaflets"
  foliicolous
  A growth habit of certain lichens, algae, and fungi that prefer to grow on the leaves of vascular plants.
  follicle
  A dry fruit formed from one carpel, splitting along a single suture, to which the seeds are attac
caption: Emerging leaves of Oldenburgia grandis are heavily felted.
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