H.1.2 Seedling Terms

Allelopathy The process in which a plant releases into the environment a chemical compound that inhibits or stimulates the growth of another plant in the same or neighboring habitat.

Deciduous Falling off or shed at a specific season or stage of growth (i.e. deciduos leaves or deciduous antlers).

Evergreen Having foliage that persist and remains green throughout the year.

Forest Stratification Distinct vertical layers of leaves that may be observed within forests. Forest layers from top to bottom are listed below.

• Canopy The uppermost layer of leaves formed by the crowns of the tallest trees.
• Understory Leaf layer beneath the canopy formed by smaller trees and tall shrubs (not always present, especially in young forests).
• Shrub Layer Beneath the Understory and above the herb/fern layer, leaf layer made up of small shrubs and young trees.
• Herb/Fern Layer Just above the ground surface, leaf layer formed by ferns and wildflowers.
• Litter Layer The ground surface of the forest composed of a layer of decomposing leaves and wood.

Growth Rate A measure of how quickly a tree increases in height and width (Sunlight, nutrients, water and soils strongly influence a trees Growth rate).

Habitat An environment in which you expect to find certain species of plants and animals.

Indicator Species Plant and animal species used to identify different types of habitats

Longevity Length of life.

Nursery A place where plants are raised.

Salt Tolerance The ability of an organism or thing to resist damage from exposure to salt.

Scientific Names Every organism has a unique scientific name. A scientific name consists of two words: the genus name (capitalized); and the species name (lower case).(Family, Genus & Species)

Seedling A young plant that is grown from a seed.

Shade Tolerance The ability of a tree to grow with minimal sunlight.

Silviculture The care and cultivation of forest trees.

Soil Moisture The amount of water present in the ground. In particular, the amount of water available to plants. Common terms to indicate the amount of moisture in soil are listed below.

• Hydric wet soils (ex. a swamp)
• Mesic moist soils, not too wet or dry.
• Xeric dry soils (ex. sand dunes or mountain bluff)

Solar Energy energy obtained from the sun.

Tree Succession the sequential progression of tree species that occur in a habitat after a major disturbance (i.e. a wildfire or tornado).

• Pioneer Species the first trees to appear after a major disturbance. Typically very fast growing trees that thrive in full sunlight.
• Seral Species trees that are not true pioneers or climax species. Typically have moderate growth rates and moderate shade tolerance.
• Climax Species the last trees to appear in succession that can maintain their presence in a habitat with the absence of major disasters. Typically very shade tolerant.