MÔN QUẢN LÝ THẢM THỰC VẬT: artificial regeneration 2

After two growing seasons in the field

Transplanted seedling

Direct-seed

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Two types…

Bare-rooted seedling

Containerized seedling

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Containerized Seedlings

Moved to the field in the soil that they were grown. Planted with the soil still attached to the roots

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Bare Root Seedlings

 Roots separated from the soil in which they were grown before
they are planted

 Survival depends on quick re-establishment of functional contact

between the roots and the soil

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Bare root Vs. Containerized

 Containerized: Extended planting season, better control of germination/growing conditions, shorter nursery
rotations, uniformity of size/condition, undisturbed roots, protection of roots

 Bare-root: cheap to produce, low bulk, easier to transport & handle
in field

Differ from temperate regions, There is no winter resting
period in tropical countries so bare root seedling rarely
survive and mainly container plants are produced

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Containerized seedling

Seed collection

Seed storage

Pre-treatment of seeds

Sowing the seed

Container preparing

Transplanting germinated seedlings

Tending

Quality of mother trees; timing
o
Low moisture (4-12%); low temp. (<5 C); Dark room

Chemical; mechanical; boiled water

Method (strip/ row/ spot); timing; density

Size; material (soil, fertilize, nutrition)

Techniques

Watering; covering; fertilizing
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Planting technique

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Container size

7 x 12 cm

9 x 13 cm

10 x 15 cm

13 x 18 cm
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Quantity of sowing seeds
The number of sowing seeds (X) can be calculated as follows

NP. 10
X=
ER

Whereas
2
X (gr): Quantity of sowing seeds/m or m
2
N: The number of reasonable seedling/m or m
P (gr): The weight of 1.000 seeds
E (%): Germinate rate
R (%): Pure rate (Plump seeds/total number of seeds)
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Quantity of seedlings

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Seedling Size

Caliper-diameter

at root collar (most common
measure of seedling size)

Height

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Seedling Size

Best indicator of seedling’s chances of survival


Relative growth
rate



Size relative to
competitors



Resistance to damage

The less dense you plant seedlings the bigger they will be in a given period of time

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Planting

Transplanting of bare rooted seedlings is rarely done in the tropics, common practice in temperate regions
Transplanting of contained seedlings is the standard method in the tropics.

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Planting

Planted seedlings will grow faster initially than seedlings from seed
With planting, wood yields are generally better than with seeded stands

Initial costs may be higher than for natural regeneration and direct seeding
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Hole size

30 x 30 x 30

40 x 40 x 40

50 x 50 x 50

The most common and proven technique is the
planting hole method

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Planting stock (density)
Big hard wood trees

1.660/ 2.500/ 3.300

Mangletia conifera
Pinus sp.
Canarium album
Chukrasia tabularis
…
Sawed wood (small wood)

2.200/ 2.500/ 3.300/ 4.500

Acasia sp.
Eucalyptus sp.
Melia azedarach
Styrax tonkinensis
…

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Square vs. Triangle

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Field planting

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Tending after planting

Weeding
Fertilization
Protecting from animals
Replanted: failures below 10% are generally not replanted because of the high costs

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Assessing

 To assess the success of your regeneration efforts, it is
necessary to check survival of the seedlings.

 One year after planting, seeding, or natural regeneration
has occurred, is a good time for assessment.

A

number of plots should be taken over the entire
planting site to get an idea of success over the entire site.

r ~ 5,67 m

Plot area = 100m2
Assessing area = 5-10% total area

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