Module 5 Flashcards
CODIT
Wall 1-vertical vascular system, plugs tracheids and xylem vessels
Wall 2-resists decay round the center of tree, latewood cell
Wall 3-resists from the point of injury around the trunk. Toxic to decay microorganisms.
Wall 4-prevents from moving outward
Vessel
Tube water conducting cells xylem In angiosperms.
Tracheids
In gymnosperms, elongated tapering xylem cell transports water
Parenchyma
Thin walled living cell essential in photosynthesis, radial transport, storage, protective compounds
Cellulose
Strings, whitish in color, provide flexibility and strength under tension.
Lignin
Darker brown, blocks surrounding strings, provides stiffness and load Bering capability when under compression.
Rays
Specialized parenchyma cells that develop radially across the xylem and phloem
Response growth
New wood produced in response to loads and damage; includes reaction, flexure and woundwood. Response includes swelling, ridges, bulges. Compression and tension.
Reaction wood
Wood formed in leaning or crooked stems, upper or lower branches, counteracting gravity. Compression and tension wood.
Compression wood
Common in gymnosperms is response to increased static load, due to gravity. Formed downslope or under branch. Expand longitudinally.
Tension wood
Formed in angiosperms. Form on upper side of a branch or uphill side of the trunk. Pulling trunk vertically. Conifers do not produce tension wood.
Flexure wood
Formed in response to wind loading. Example is trunk taper and buttress roots.
Woundwood
Responds to cambial damage. Produces callus. Can produce rams horn, curl inward.
Saprophytes
Decay that attacks non living cells
White rot
Break down mostly lignin and some cellulose, leaves wet spongy wood. Fibrous appearance. Mostly in hardwood
Brown rot
Primarily breaks down cellulose. Brittle and crumbly, wood shrinks and cracks into blocks. Loss of strength. More serious.
Soft rot
Decay of plant tissues characterized by the breakdown of tissues within cell walls. Breaks down cellulose first. Creates localized pockets of decayed wood softer than surrounding areas.
Decay progression relates to:
Tree and fungus characteristics Codit Age and vigor at time of injury Type of pathogen Interaction btw fungus and tree species Recent Additional wounds Site moisture and temp