|Forestry Training Manual: Inter-America Region (Peace Corps, 1986)|
- To refresh the memories of the trainees about flowering cycles, pollination, seeds, seed germination, seed dispersal, basic seed storage and point out the lack of knowledge we have about seed germination and dispersal among many tropical species. To instruct the trainees in basic seed storage .
- Enable trainees to set up seed collection records.
- Conduct seed germination experiments.
- Look at small group process.
This session is a review of the flowering cycle and seeds from pollination to germination. It is necessary to start at. the beginning here as most trainees will have studied these cycles in North America and need to see the differences, particularly in tropical species. The trainees will also have "hands-on" experience in treating seeds (stratification and scarification) and setting up a simple experiment and keeping records.
1. Lecture on flowers & seeds
2. Germination experiment
3. Small group process
- flip charts, marker pens, tape
- 20 different varieties of seeds about 300 or 400 in all
- small plastic hays
- blotter paper or newspaper
Flowers & Seeds
Total time - 1 hour
Many of the participants will have learned in North American schools the cycles of flowering and seed development. However, the purpose of this lecture is to refresh their memories and have them relate the cycles to the Latin American forests and trees.
1. Trainer/forester states that this morning is a quick refresher
for everyone and invites a botanist in the group to join in and add his/her
comments throughout the lecture. It is recommended that the following outline he
put on newsprint and trainees follow it as lecture is
1. Many different types.
2. Complete flowers - bisexual.
3. Staminate (male) flowers and pistillate (female) flowers on same tree, monaecius (pines; Douglas-fir).
4. Staminate and pistillate flowers occurring on separate trees (willow; poplar).
5. Polygamo - monoecius - complete flower plus staminate and pistillate flowers on same tree (Buckeye).
6. Polygamo - Dioecious - perfect flowers plus either staminate or pistillate flowers (Buckthorn).
Note: All of the above type trees can hear seeds except the dioecious tree that produces staminate flowers.
FLOWERING CYCLE/SEED MATURITY POLLINATION
d. Others- mice, bats
Two nuclei penetrate the ovule and double fertilization occurs.
1. One fertilization unites to egg forms embryo.
2. Other fertilization unites with two polar nuclei to form endosperm.
I. Mature Seed
A. Three - six months after fertilization
B. 1 year after fertilization - Pine
C. Some take more time
A. Mature embryo embedded in endosperm (endosperm can be small or absent).
B. Seed coat (integument) forms around the ovule.
III. Embryo = Germ
A. Composed of:1. Seed leaves - Cotyledon - mostly two (palms 1, pines 4+)a) manufacture food or
b) have stored food
2. Bud - Plumule
3. Stem - Hypocatyl
4. Rudimentary root - radicle
5. Seed Coatsa. hard (Pines)
c. leathery (Cypress)
IV. Types of Seed
A. True seeds (from Pine)
B. Dry fruits; fruit is seed (oak)
C. Fleshy fruit (apple)
A. Chemical change
D. Color change
VI. Seed Dispersal
A. Wind1. light seeds
2. Seeds w/wings
B. Mammals - Birds1. Rodents
VII. Seed Collection - Records
A. Seed Maturity
C. When to collect1. early collection - not ripe
2. late collection - few viable seeds left
D. Methods1. climbing
6. bamboo poles
7. collect off ground
8. spread sheet below tree
E. Seed Extraction1. air dry
2. oven kiln
*Note: Important in air drying that birds do not eat seeds. Air drying is also the most used and practical method.
F. Seed Treatment1. burning
4. filing - soaking
5. cutting - soaking
6. tumbling - (with grit)
Internal dormancy (triggering internal chemical reactions) External dormancy ( seed coat permeability)
To Take Place1. internal factor - ripe
2. external factora. moisture
H. Seed Storage1. dry - cold: In sealed containers: Pine (pino), Cypress (Ciprés)
2. moist cold: Oak (roble), Maple (arce)
3. room temperature: Acacia (acacia), Eucalyptus (eucalipto)
4. other possibilitiesa. partial vacuum
b. dry freeze
c. hole in the ground - bury in sealed plastic bags.
5. how does nature to it? peat moss (turba)
6. small containers
Total Time: 2 hours
The purpose of this exercise is to give trainees "hands-on" experience and to apply learnings from previous exercise. Trainees will also develop a record keeping system for their experiments which will reinforce learning from record keeping exercise of the previous day.
1. Trainees are asked to form groups of three. Groups are given a
variety of seeds .
2. Groups are told that they are to figure out the best way to
treat the seeds (scarify and/or stratify). They must decide three (different
methods with at least two varieties of seeds. They are told the
Trainer's Note: The purpose of this exercise is not
to furnish all the materials trainees need, but to have them find their own
boiling water, sand paper, finger nail files etc., at the training site. Plastic
hags, seeds and blotter paper are provided.
3. Trainees are told to figure out a record keeping system for the
4. Trainee/manager is identified; the groups are to report their
data on progress of germination experiments to manager every three
Trainer's Note: Trainer or expert in seed management should present the most applicable procedures and record keeping system used for germination text. Obtain feedback on students' efforts.
Small Group Process
The purpose of this exercise is to look at small group process as compared to larger group process of the previous day. We also make use of feedback skills.
1. Trainers look at the process of their groups. They are told to
give each other feedback on the following:
a. leadership qualities
c. what helped/hindered getting task done. Everyone must get/give
feedback. While one is giving feedback to another, the third trainee observes
the quality of the feedback and gives feedback on the quality and skill used for
2. Trainees are asked to compare working in a small group to
working in a larger group.
3. Trainer lists on newsprint findings of various groups as
- things that are harder,
- things that are easier,
- impact on individuals.
4. Trainer points out the greater responsibility of human
interactions as trainees work together and become more