SFI 30 (LEC) 4

Evaluation

For species and

provenance trials; pilot

plantations

Conservation

Ex-situ germplasm,

collection, gene bank

Utilization

Operational planting

programs like

reforestation,

commercial/industrial

tree plantations, tree

farms

Climate

Location of seed source

Condition of the stand

Nature of individual trees

Type of fruits/ seeds

Level of maturity of fruits or seeds

Factors to consider in the choice of

collection method

Collecting from the Ground

Best for species this method of collection

▪ Produce large fruits that fall

unopened when ripe

▪ Have large, heavy seeds not

dispersed by wind

▪ Bear fruits that are large but not

wind disseminated

▪ Seeds not prone to predation or

rapid deterioration after falling

▪ Mature quickly

Collecting from Standing Trees

Best for species that:

• Have wind-disseminated fruits (e.g., palosanto, taluto)

• Produce small seeds that fall while fruits are still attached

(e.g., ipil-ipil, kupang, banuyo, kamachile)

• Bear fruits with light, wind-disseminated seeds (e.g., B.

pine, banaba, agoho, african tulip, balsa, kalantas)

• Produce fruits too small to collect economically from the

ground (e.g., malaruhat, molave, tuai, amugis,

malapapaya, eucalyptus)

• Have low trees or drooping branches

Collecting from Felled Trees

Best for species that:

• Grow very tall, making crown access difficult while standing

• Produce fruits/seeds located at the top canopy

• Are harvested during logging, thinning, or storm damage (opportunity for

seed recovery)

• Have hard-to-reach fruits that are uneconomical to collect by climbing

at least 30 trees
different parts of the crown
only mature seeds
seed collection record

Basic Seed Collection Guidelines

Ripeness or maturity
Knowledge of seed maturity

Factors Affecting Time of Seed Collection

Physiological Maturity

Stage of seed development when maximum growth is reached

• Generally indicated by maximum dry weight

Harvest Maturity

• Stage when seeds are ready for collection

• Usually occurs just before natural dispersal

Indices

• Most practical and easiest method

• Focus more on shading intensity than just basic color

• Mature seeds usually have a darker shade

• Common color transitions:

• Green → Yellow → Brown → Black/Violet

External indicators

• Change in fruit or cone color

• Cone firmness

Internal indicators

• Examination of embryo and endosperm development

• Determination of seed specific gravity and moisture content (cones in

particular)

• Chemical composition analysis

Physical properties

• Seed brittleness

Chemical Composition

• Mature seeds show accumulation of food reserves:

• Starch

• Hemicellulose

• Lipids & fats

• Proteins

• Provides a good estimate of seed maturity

• Limited application in the field

• Research for tropical species still lacking

Moisture Content & Specific Gravity

• Steady decline in seed moisture during ripening:

• From 80–90% → 10–20% (depending on species)

• Measured using a moisture meter

• Considered more accurate and reliable indicator of

maturity

Endosperm & Embryo Development

• More reliable method compared to external indicators

• Endosperm of old seeds loses color and freshness

• Embryo may shrivel and only partially fill the cavity

• Can be assessed by:

• Physical examination (cutting fruits/seeds)

• X-ray radiography

Cutting and Pruning tools
climbing and access tools
processing tools
collection aids

Tools for

Seed

Collection

Tree pruner
Pruning hooks
Sharp bolos

enumerate the types of cutting and pruning tools

Climbing irons

Ladder

Ropes

Enumerate the types of climbing and access tools

Seed seperators
Macerating machine

Enumerate the types of processing tools

Canvas
Nets
Buri mats

enumerate the types of collection aids