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
- 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.
- Buffer
- An area of natural vegetation along a stream, wetland, or other natural feature, which acts as a filter to keep the environment more healthy
C
- Calyx
- The outer ring of flower parts, or sepals.
- Canopy
- The highest vertical level of vegetation in a forested habitat.
- Capillary Action
- Natural movement of liquid upward through small vertical openings.
- Capsule
- A dry fruit which splits at least partially open at maturity.
- Carnivore
- An animal which subsists soley by eating the flesh of other animals.
- Catkin
- A dry, oblong pendulant flowering spike.
- Cell
- The simplest unit of life.
- Chrysalis
- The outer cover of a butterfly pupa, where metamorphosis occurs.
- Class
- The taxonomic division more general than an Order and more specific than a Phylum.
- Cold Blooded
- Animals that regulate their heat by relying on their surroundings, such as fish, reptiles, and amphibians.
- 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
- Diversity
- Having a wide range of variation, either genetically, in terms of species present,habitat type, or otherwise.
- Downy
- Being densely covered with soft, short, fine hairs.
E
- Ecosystem
- A complex, interwoven community of plants, animals, and their environment, linked by natural processes and geography.
- Ecotone
- An edge; a transitional area between two habitat types, or between successional stages of a single habitat type.
- Elliptical
- Oval shaped.
- 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.
- Estuarine
- Areas of high biological productivity found where a river meets the sea.
- 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
- Family
- A taxonomic group more general than Genus, and more specific than an Order.
- Fen
- A wetland with an alkaline pH, often fed by groundwater seeps or springs, and occurring on calcareous substrates.
- Floodplain
- The flat area adjacent to a stream or river, where floodwaters may accumulate and dissipate their destructive energy.
- Forb
- Broadleaved, herbaceous plants that are not grasses.
- Fungus
- A primative plant-like form of life lacking chlorophyl.
G
- Genus
- A taxonomic category more general than Species, and more specific than Family.
- 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
- Habitat
- An environment providing for the basic needs of a plant or animal organism.
- Herb
- A plant without a woody stem, including both grasses and forbs.
- Herbivore
- An animal that eats only plant material.
- Hydric
- Having an abundance of water, or being adapted to such conditions.
I
- Indicator
- An easy to observe element that provides useful information beyond the simple observation. For example, observing Sphagnum moss may indicate that the soil in the area is acidic and wet, which in turn may allow a naturalist to look for certain other plant
- Involucre
- A cluster of bracts under a flower.
J
K
- Kingdom
- The top taxonomic level-The Plant Kingdom, for example.
L
- Lanceolate
- Lance-shaped; longer than wide, tapering to the tip.
- Larvae
- An immature stage of animal life.
- 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.
- Litter
- The organic debris on a forest floor; Leaves, twigs, and other lightweight decomposing material.
M
- Marsh
- A wetland dominated by emergent grasses.
- Meadow
- A field of grasses and forbs.
- Mesic
- Intermediate in moisture level, between hydric (wet) and xeric (dry).
- Metabolism
- The physical and chemical process of transforming food or other energy sources into a form useful to living organisms for energy or nutrients.
- Mitochondria
- Organelles of a cell which are sell-reproducting, and provide energy to the cell.
- Mitosis
- The process of cell division, whereby two genetically identical cells are created from one cell.
- Monoculture
- A stand of plants containing only one species, such as a cornfield, or a wetland completely overtaken by reed canary grass.
N
- Native
- Indiginous; originally from the place, and not introduced by humans.
- Naturalized
- A species introduced from elsewhere which has become widespread and integrated into the native plant communities.
- Nature
- The physical world around us, including the complex webs of life, geological formations, plant communities, assemblages of animals, and the other phenomena of the world.
- Node
- Where a bud or leaf is attached to a stem of a plant.
- Nucleus
- The portion of a cell containign the genetic data that determines the function and behavior of the cell.
O
- Obovate
- A leaf shape resembling an elongated egg, with the widest part above the middle.
- Old Growth
- A forest stand near or at its peak of development, including trees of great age, pit and mound topography, an abundance of down and standing dead wood, and limited or no evidence of human influences, such as stumps, logging roads, or other man-made distur
- Omnivore
- An animal that subsists on both plants and other animals.
- Opposite
- With leaves arranged directly across from one another on a stem, as opposed to Alternate, or Whorled leaf arrangements.
- Order
- A taxonomic group more general than Family, and more specific than a Class.
- Orient
- To arrange a map using a compass so that the directions of the map correspiond with the surrounding landscape, so that North on the map is facing true North, etc.
- Ovate
- A leaf that is generally egg shaped.
- Overstory
- Trees composing the canopy layer of a forest; the highest trees.
- 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.
- Palustrine
- Related to or near a marsh or wetland.
- 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.
- Phylum
- The taxonomic division more general than a Class and more specific than a Kingdom.
- 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.
- Pupa
- A developmental stage in the lifecycle of insects, generally a dormant stage, taking place in a cocoon in some cases.
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
- Riparian
- Related to or near a river or stream bank.
- Riverine
- Related to or in a river.
- Root Hair
- Small structures on the roots of plants, which abosorbs nutrients from the soil.
- Rosette
- A cluster of spreading leaves.
- Runoff
- Water that is shed during and after rain, which does not soak into the ground.
- 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.
- Stochastic
- Having the attributes of random chance.
- Stoma
- A small opening in a leaf, where air can enter and exit.
- Stomata
- Plural form of Stoma.
- Swamp
- A forested wetland with significant areas of standing water for at least portions of the year.
T
- Taproot
- A thick central root which anchors some plants.
- Taxonomy
- A hierarchical system of naming and classifying living things scientifically.
- Topography
- The lay of the land, in terms of vertical relief, portrayed on maps as contour lines of elevation.
- Transpiration
- Loss of water from plants through the leaves.
- 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.
- Understory
- A layer of woody vegetation under the canopy of a forest, the shrub and tree layer below the dominant stratum.
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.
- Vertical Structure
- The different layers of vegetation in a forest, from groundcover to canopy trees.
- Virgin Forest
- A forest that appears to have never been cut. Whereas an old-growth forest may be second growth, a virgin forest has never been harvested.
W
- Warm Blooded
- Animals that create their own warmth through metabolic processes and do not rely totally on their environment for their body temperature.
- Weathering
- The processes by which rock becomes soil.
- Whorled
- A leaf arrangement wherein three or more leaves arise around the same point on a stem, as opposed to Alternate or Opposite.
X
- Xeric
- A dry habitat, as opposed to mesic (intermediate) or hydric (wet).
- Xylem
- Plant vascular tissue which moves water and nutrients from roots to leaves.
Y
Z