Forestry Science I Unit 3 Lesson 2 Created

Forestry Science I Unit 3 Lesson 2 Created by Ms. Holli Bowman FORS 7730 Fall 2001 Modified by Georgia Agricultural Education Curriculum Office July 2002 And CTAE Resource Network, 2010

Annual Rings • Annual rings are formed by division of the cambium layer • Each ring is composed of two cell walls – Summerwood -- a darker-colored area of small, dense, heavy walled cells – Springwood -- a lighter-colored area of large, thin -walled cells.

Annual Rings • Annual rings vary in width for several reasons: – amount of room tree has to grow -- how close it is to other trees – Rainfall amounts – Drought – Natural Disasters (fire, insect damage, etc…)

Annual Rings • False ring -- a false ring may be formed when very favorable growing conditions may occur when a tree is growing slowly which may result in an additional ring of wood in a given year. Characteristic of pines and some broadleaf trees. • Tolerance -- the ability of a tree to endure shade.

Tree Reproduction • Trees reproduce in three ways: – by seed – by sprouts – by suckers • Seed is the most common way for a tree to reproduce. • Broadleaf trees sprout profusely. • Suckering is the sending up of shoots from underground roots.

Seed and Flower Production • Fruits and seeds are NOT the same. • In hardwood trees, a fruit is usually the ripened ovary of a flower. • The ripened ovules of the ovary are the seeds of the fruit. • Monoecious species -- if the male and female flower parts occur in separate flowers on the same tree • Dioecious species -- if the male and female flowers occur on separate trees

Parts of the Flower • Ovary -- the enlarged portion at the base of the pistil. • Ovules -- parts of the ovary that, when ripened, comprise the seed of the fruit. • Calyx -- the sepals of the flower, when grouped as one part. • Corolla -- the petals of the flower, when grouped as one part. • Pistil -- the female portion of the flower, consists of the stigma, the style and the ovary. • Stamen -- the male part of the flower, consists of the anther and the filament.

Types of Flowers • Complete Flower -- a flower which contains all parts • Incomplete Flower -- a flower which lacks one or more of the following: a calyx, corolla, stamen, or pistil

Pine seed definitions • The ovules of conifers are “born naked” on cone scales and are not enclosed in an ovary. • Carpelate -- female cones which pine seeds are produced on. • Sacs -- clusters of staminate pollen-bearing cones. • Most pine species require two years for the seed to mature.

Seed Dispersal • Seeds are dispersed by several means: – – – Wind Birds Animals Streams / Other water Humans Simply falling to the ground