Nature Terms
A Brief Glossary for Nature Lovers, Natural Historians, and other folks interested in Biology.
A
- Achene
- A small, dry fruit with one seed
- Alternate
- With leaves arranged in a staggered fashion, as opposed to directly opposite one another. examples of trees with alternate leaves.
- Annual
- A plant which completes its entire lifecycle, from germination to setting seeds, in one year.
- Aquatic
- Plant or animal life adapted to water
- Aromatic
- Having a strong fragrance
- Axil
- The point where a leaf meets the stem of a plant
B
- Basal Area
- The cross-sectional area of a tree or other vegetation. A measure of the volume of plant life in a forest or other habitat.
- Basal Leaves
- Leaves arranged at the lowest portion of a plant, generally at ground level.
- Bog
- An acidic wetland habitat with no natural surface water inlet or outlet, with an accumulation of Sphagnum moss.
- Bracts
- A leaf-like growth below a flower
- Bud
- A small protrusion on a stem which consists of immature cells that may later form a leaf, additional stem, or flowers.
C
- Calyx
- The outer ring of flower parts, or sepals.
- Capsule
- A dry fruit which splits at least partially open at maturity.
- Catkin
- A dry, oblong pendulant flowering spike.
- Compound Leaves
- Leaves composed of more than 1 leaflet.
- Corm
- A small, roundish underground plant stem structure used to store energy.
- Corolla
- Collectively, all the petals of a flower.
- Corymb
- A flat-topped flower structure, in which the outer flowers sit upon longer pedicels, and the inner upon shorter pedicels.
- Cotyledon
- Seed leaf, the first leaf of a germinating seed.
D
- Deciduous
- A plant which sheds its leaves during some portion of the year.
- Diameter at Breast Height
- A standard measurement of tree growth in inches or centimeters, by convention taken at a point 4.5 feet from ground level.
- Dicot
- A plant having two cotyledons, or seed leaves.
- Disc Flower
- Small, inner cluster of flowers in a composite, such as the yellow part of a daisy flower.
- Dissected
- Finely divided leaves; lacelike
E
- Elliptical
- Oval shaped (in this sense usually refering to leaf shape).
- Emergent
- Aquatic plants having some or most of the leaf area extending out of the water.
- Entire
- A leaf with neither lobes nor teeth on the margins.
- Even-aged
- A forestry term meaning that the dominant trees in a forest stand are roughly of the same age.
- Evergreen
- Plants that keep their leaves throughout the year, such as white pine or Norway spruce.
F
- Forb
- Broadleaved, herbaceous plants that are not grasses.
- Fungus
- A primative plant-like form of life lacking chlorophyl.
G
- Glandular
- Bearing structures which secrete moisture, or that resemble glands.
- Glaucus
- Having a bluish-white coating which disappears when rubbed.
- Grass
- Members of the Family Gramineae; generally narrow-leaved green monocots.
H
- Herb
- A plant without a woody stem, including both grasses and forbs.
- Herbivore
- An animal that eats only plant material.
I
- Involucre
- A cluster of bracts under a flower.
J
-
K
L
- Lanceolate
- Lance-shaped; longer than wide, tapering to the tip.
- Leaf Scar
- The remnant marking a spot where a leaf had been attached to a woody plant.
- Leaflet
- Small leaves which together make up a compound leaf.
- Lenticel
- Slightly raised areas on the bark of a tree.
M
N
- Node
- Where a bud or leaf is attached to a stem of a plant.
O
- Obovate
- A leaf shape resembling an elongated egg, with the widest part above the middle.
- Opposite
- With leaves arranged directly across from one another on a stem, as opposed to Alternate, or Whorled leaf arrangements.
- Ovate
- A leaf that is generally egg shaped.
- Ovoid
- A leaf that is generally oval, rounded on both ends.
P
- Palmate
- A compound leaf arranged so that all leaflets emanate from one point, shaped roughly like the palm of a hand.
- Panicle
- A flower stalk having a main stem and branches, with the lower fowers opening before those higher on the stem.
- Perennial
- A plant that contiues to grow more than one year, as opposed to an Annual.
- Pedicel
- The stalk of an individual flower.
- Petal
- Modified leaves surrounding the reproductive portions of a flower; the individual parts of the corolla.
- Petiole
- The stem of a leaf, which attaches the leaf to the main stem of the plant.
- Phloem
- A portion of the stem of a plant that conducts fluids from the leaves to the roots, composed of small tubes,
- Photosynthesis
- The process whereby plants convert sunlight, carbon dioxide, and water into useful energy.
- Pilose
- Covered with long, thin, soft hairs.
- Pinnate
- A compound leaf with the individual leaflets arranged opposite one another on a central stalk.
- Pistil
- The female reproductive structure of a plant, made up of the stigma, style and ovary.
- Pith
- The white, spongy substance found inside the stem of many plants.
- Pod
- A dry, sometimes flattened fruit of a plant, bearing one to many seeds.
Q
R
- Raceme
- A flower spike with the flowers all being attached to a main stem, either directly, or on pedicels.
- Ray Flowers
- The outer flowers of composites, generally giving the appearance of petals.
- Rhizome
- An underground, horizontal stem
- Root Hair
- Small structures on the roots of plants, which abosorbs nutrients from the soil.
- Rosette
- A cluster of spreading leaves.
- Rush
- A grass-like plant with long round stems, which usually grows in wet areas.
S
- Sedge
- A grass-like plant with flat, generally keeled leaves, which usually grows in wet areas.
- Sepal
- A part of the calyx of a flowering plant, usually a greenish bract subtending the petals.
- Shrub
- Low growing (to 15 feet) woody plants, usually composed of multiple stems radiating from the same point near the ground.
- Simple Leaf
- A leaf composed of only one undivided leaflet on a single petiole.
- Species
- In taxonomy, the division below Genus, which consists of individuals which produce viable offspring.
- Stamen
- The male reproductive organ of a flowering plant, composed of a filament and an anther.
- Stigma
- A part of the pistil, the top of the style, where pollen enters the Pistil.
- Style
- The tube connecting the Stigma to the Ovary in a flowering plant.
- Stipule
- A small, leaf-like bract at the base of a petiole, usually found in pairs, one on each side of the petiole.
- Stoma
- A small opening in a leaf, where air can enter and exit.
- Stomata
- Plural form of Stoma.
T
- Taproot
- A thick central root which anchors some plants.
- Tree
- Large woody plant which matures to a hieght greater than 15 feet, and is perennial.
- Tuber
- A fleshy root or swollen underground stem.
U
- Umbel
- A flower structure shaped like an umbrella.
V
- Vascular Bundles
- Strands of xylem and phloem in a leaf stem, the remanants of which can be seen in leaf scars on winter twigs.
- Venation
- The pattern of veins in a leaf.
W
- Whorled
- A leaf arrangement wherein three or more leaves arise around the same point on a stem, as opposed to Alternate or Opposite.
X
- Xylem
- Plant vascular tissue which moves water and nutrients from roots to leaves.
Y
Z