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Glossary: S is for ... samara, sapling, and subkingdom.
by Ariadne Unst

Glossary of S...

S-shaped curve (n.)
In population growth, a growth (for example, in population) with time, which culminates in a levelling off in numbers.
Compare with J-shaped curve.

samara (n.)
A dry, indehiscent, winged fruit, one-seeded (like Fraxinus and Ulmus) or two-seeded (like Acer).

sap (n.)
The juice of a tree or other plant. It transports the materials required for growth.

sapling (n.)
A tree more than 0.9 in (3 ft) in height and less than 10.2 cm (4 in) in d.b.h.

saprophyte (n.)
Plants that absorbs soluble organic nutrients from decomposing plant or animal matter. They live in the buttresses of trees or on the forest floor. They include bacteria, fungi, and orchids. Usually they lack chlorophyll.

saprophytic (adj.)
A decomposer that is a plant (or plant-like) and that absorbs soluble organic nutrients. Common examples are fungi.

savanna (n.)
Lowland tropical and subtropical grassland, generally with a scattering of trees and/or shrubs.
If woody growth is absent it is a grass savanna;
with shrubs and no trees, a shrub savanna;
with shrubs and widely irregularly scattered trees, a tree savanna.

scabrous (adj.)
Rough; scratchy.

scientific name (n.)
Technical name in three parts:
  1. genus (capitalized)
  2. specific epithet (incorrectly though commonly called the 'species')
  3. name(s) of person(s) who first published the specific epithet for the plant.
Optionally, subspecies ("ssp.") or variety ("var.") are included.

seedling (n.)
A tree grown from seed that has not yet reached a height of 0.9 m (3 ft) or exceeded 5.1 cm (2 in) in d.b.h., which would qualify it as a sapling.

seed tree (n.)
The cutting method (in silvicultural) where all trees are removed except for a small number of seed bearers left singly or in small groups, maybe 10 per acre. The seed trees are generally harvested after regeneration is established. An even-age stand results.

sepal (n.)
One of the individual, modified leaves of a calyx and surrounding a plant's reproductive organs.

sere (n.)
A sequence of plant communities that successively follow one another in the same habitat from the pioneer stage to a mesic climax.

sessile (adj.)
Without a stalk; sitting directly on its base.

shade-tolerance classes (n.)
Very intolerant, intolerant, intermediate, tolerant, very tolerant.

shelterwood (n.)
A silvicultural cutting method in which, in order to provide a source of seed and/or protection for regeneration, the old crop (the shelterwood) is removed in two or more successive shelterwood cuttings. An even-age stand results.

shrub (n.)
A small, woody perennial plant with several stems.

simple (adj.)
Describes a leaf that has a single part, without subdivision into leaflets.

species (n.)
1. Freely interbreeding population of organisms. The organisms in a species usually share a large number of characters. Their offspring are fertile. (Some species can interbreed, but their offspring are infertile.)
2. Generally the lowest level in a taxonomy. A category of animals or plants below a genus. Sometimes breed is specified below it, such as for cultivated plants.

species loss (n.)
Our world loses about 1 species per day to extinction, of about 10 million species thought to exist. Concerning mammals and birds only, we lose about 1 species per year out of about 13,000.

species name (n.)
Our world loses about 1 species per day to extinction, of about 10 million species thought to exist. Concerning mammals and birds only, we lose about 1 species per year out of about 13,000.

spermatophyte
A subdivision of vascular plants that consists of ferns and their allies. Contrast with pteriodophyte.

stabilizing selection (n.)
Natural selection where species survive by maintaining existing characters. An individual that exhibits an extreme variation of any critical character is eliminated. The population narrows in the expression of adapted traits. Stabilizing selection maintains the existing state of adaptation. Compare with disruptive selection.

stamen (n.)
The pollen-bearing male organ of a flower, composed of filaments and anthers.

stand density (n.)
The degree of crowding of trees, expressed by various growing-space ratios such as crown-length to tree-height, crown-diameter to diameter-at-d.b.h..; or crown diameter to tree height.

stand structure (n.)
The distribution of tree sizes and species on a forested area.

stem (n.)
Main axis or stalk of a plant, growing upward above the ground; bears the leaves and flowers.

stemflow (n.)
Precipitation intercepted by vegetative cover. It runs down the stem or major axes of such cover.

steppe (n.)
Arid land with xerophilous vegetation found in regions of extreme temperature range and loess soil.

stigma (n.)
The part of the pistil (usually the tip, often sticky) that receives the pollen and upon which the pollen germinates.

stipe (n.)
A supporting stalk. Example: the stalk of a pistil, a gill fungus, or the petiole of a fern leaf.

stipule (n.)
[From Latin stipula = stalk.} One of a pair of leaf-like appendages that are at the base of the petiole of some leaves.

stoma (plural = stomata) (n.)
Tiny pore in the leaves and stems of plants. Gaseous diffusion (of carbon dioxide, oxygen, and water vapor) can occur through the pore.

style (n.)
The stalk of a pistil which connects the stigma with the ovary.

superior ovary (n.)
An ovary located above the perianth and free of the calyx.

suppressed (adj.)
Very slowly growing trees with crowns in the lower layer of the canopy and leading shoots not free. Such trees are subordinate to dominants, codominants, and intermediates in the crown canopy.

subdivision (n.)
Four subdivisions:

subkingdom (n.)
See phylum.

sympodial (adj.)
A branching growth pattern in which the main axis is formed by a series of successive secondary axes, each of which represents one fork of a dichotomy.

synecology (n.)
The study of ecological communities, or of a complete living community in its relationships with the environment. The study of entire plant and animal communities, including ecosystems.
More complex than autoecology, because it involves far more variable factors.
From Schroter (1800s).