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Botanical Terminology Tutorial
Leaf Arrangement
Leaf Shape
Leaf Margin
Leaf Apex
Leaf Base
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Alphabetical w/ Definitions

  1. Sapwood
    The outer and lighter wood that is actively transporting water.

  2. Scabrous
    Rough texture due to short stiff hairs or the epidermal cells.

  3. Scale
    A small dry bract acting as a covering or layer.

  4. Scale-like
    Having small overlapping layers.

  5. Schizocarp
    A dry dehiscent fruit that breaks apart into two halves.

  6. Scurfy
    Covered with small bran-like scales.

  7. Serrate
    Sharp forward-pointing teeth along leaf margin.

  8. Serrulate
    Many minute sharp forward-pointing teeth along leaf margin.

  9. Sessile
    Attached directly without a stalk; a leaf or flower directly attached to a stem.

  10. Shoot
    A young green stem.

  11. Shrub
    A small woody plant with multiple stems from the ground and that is not usually climbable; all of the branches are produced from or near the base.

  12. Simple
    A single undivided leaf. A simple leaf may have lobes, or serrations (See also Compound).

  13. Sinuate
    Strongly wavy margins only in one plane; close to being lobulate (See also Undulate).

  14. Sinus
    On a lobed leaf a sinus is the valley between the lobes; they can vary greatly in size and shape.

  15. Spatulate
    Spoon or spatula-shaped, with a rounded leaf blade that tapers to the base.

  16. Spike
    An inflorescence that is unbranched with sessile flowers maturing from the bottom up.

  17. Spine
    A hard sharp woody growth that emerges from below the epidermis and is either a modified leaf or stipule (See also Thorn).

  18. Spinose
    Bearing spines along leaf margins, Tiny spines at nodes on stems.

  19. Spinose
    Having spines; having sharp woody growths.

  20. Spirally Arranged
    The actual pattern of alternate leaves on a stem;

  21. Spur
    A short shoot with leaves or fruit. Ex. Ginkgo; A hollow projection from a flower either in the sepals or petals.

  22. Stalk
    A supporting structure for a leaf, flower, or fruit.

  23. Stamen
    The male part of a flower typically consisting of an anther and filament; Commonly referred to as the androecium. (See also Pistil)

  24. Stem
    Supportive structure for buds, leaves, and nodes; can be single or branched; sometimes found underground.

  25. Sterile
    Barren or infertile; not able to produce seed.

  26. Stigma
    The recepticle for pollen on the pistil.

  27. Stipule
    A bract or appendage at the base of a petiole (usually found in pairs).

  28. Stolon
    A horizontal stem that roots at the nodes and tip and can produce a new plant (See also Rhizome and Tiller).

  29. Strobile
    A cone or an inflorescence resembling a cone. Ex. Alders

  30. Style
    The tube that connects the stigma and ovary of the pistil (the female part of the flower).

  31. Subopposite
    Leaves appear near opposite but slightly skewed at a node without a fascicle (See also Opposite and Alternate).

  32. Superposed
    Appearing one right above another; an accessory bud found above the true bud.

  33. Symmetric
    A balanced appearance; Having the same number of floral parts in any angle.

Tutorial Terms

Leaf Apex

Leaf Arrangement

Leaf Base

Leaf Margin

Leaf Shape



2005 Gary J. Kling, Laura L. Hayden, and Joshua J. Potts University of Illinois at Urbana-Champaign.
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Notes about this tutorial.