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

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 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