Dendrology (Twigs) Flashcards
Last year’s growth of a branch, eliminated by the base by the terminal bud-scale scars
Twig
A small protuberance or outgrowth on a stem or branch, sometimes enclosed by protective scales ______ and containing an undeveloped shoot, leaf, or flower.
Bud
Bud Scales
Bud located on the end or tip of a twig, it eliminates growth for the season and is where the new growth begins in the spring.
Terminal Bud
Located along the twig in the axial of the previous season’s leaves.
Lateral Bud
When a terminal bud is not formed, and growth is stopped by external forces the bud dies back to the lateral bud below. The bud appears to be atypical and is called this type of bud.
Psuedoterminal Bud
A bud inserted just above the lateral bud.
Superposed bud
Small, usually lens-shaped patches, sometimes wart-like consisting of loosely, organized tissue, which provide aeration to the tissues beneath.
Lenticel
Scars left on a twig after the stipules drop off.
Stipule Scars
Scar left on the twig when a leaf falls off.
Leaf Scar
Scars inside the leaf scar that look like bumps or dots and represent broken ends of conducting tissue which run from the stem through the petiole and into the blade where they break up into the veins.
Bundle Scars
The central portion of a twig.
Pith
Continuous and homogenous common to most trees.
Solid Pith
Featured by more or less regularly spaced disks of horizontally elongated cells with thickened walls. These appear as bars across the pith and are often readily visible to the naked eye.
Diaphragmed Pith
The pith is divided into empty chambers by cross partitions.
Chambered Pith
Modified stems. Positioned above the leaf scar in the position of the bud.
Thorns
