Transcript Paulownia Elongata - Afacerea Paulownia

Fast Growth and even faster re-growth
a great producer of light versatile wood
1983, the International Development
Research Centre of Canada has supported a
program of research by the Chinese Academy
of Forestry.
This has resulted in many new developments
in the breeding, propagation, cultivation and
management of small plantations of the tree.
The genus Paulownia is represented by nine
species of fast growing timber trees which are
indigenous to China. It is very adaptable, widely
distributed and extremely fast growing both in south and north China.
Presently, the genus is either naturally distributed or cultivated in 23
provinces, municipalities and autonomous regions.
It grows equally well on the plains as well as in mountainous regions up
to 2,000 m high.
Therefore, the genus provides a great potential for extensive cultivation
all over China.
Under normal conditions, a 10year old Paulownia tree can
measure 30-40 cm diameter at
breast height (dbh) and will have
a timber volume of 0.3-0.5 m3.
However, under optimum
conditions, they can produce
useful timber within five to six
years. For example, in Lankau
County, Honan Province,
Paulownia was planted over a
large area from 1963 to 1965 the total area under mixed cultivation
had already reached 20,000 hectares. Felling started in 1971 and it
yielded almost 148,000 m3 of timber by 1976 for the local people,
effectively solving years of timber shortage.
Current locations growing Paulownia
It is estimated that 2.5 million hectares of Chinese
farm land now has paulownia shelter belts planted
on it, from which up to 10 million cubic metres of
logs may be produced each year.
Within Asia, paulownia is grown in Taiwan, Vietnam,
Cambodia, Laos, Korea and Japan. Elsewhere,
paulownia is grown commercially in South
America and the United States, where it has
naturalised in Appalachian forests.
Plantations have also cropped up in Australia, New
Zealand, Chilie and Spain. Along side these sites,
projects for large plantations being implemented
across large parts of southern Africa.
Lightness — Paulownia is
about 2/3 the weight of
the lightest commercial
wood in the U.S.
The specific gravity of
paulownia wood ranges
from 0.23 to 0.30 (23 to
30 percent of the weight
of water).
Average cubic foot weight is 16.55 lbs. The bulk weight of
lumber averages 1,382 lbs per thousand board feet
compared to yellow poplar (tulip poplar), which weighs
2,190 lbs, or white oak, which weighs 3,337 lbs.
Strength and stability — Although the wood is light, it is
extremely strong and will not split even when spikes are
driven into it. Unlike other commercial woods, paulownia
does not split and crack with rapid drying.
Easily dried and reduced warping — Paulownia will air
dry in about 30 days with no warping. This reduces the
cost of kiln-drying. furniture made of dried Paulownia
wood is very good even under humid conditions. It
resists warping, cracking and deformation unlike poplar
wood which cupped badly and cracked at the ends, oak
checked and honey-combed and wood of other kinds
which can be severely damaged by changes in humidity.
Easily worked — Another unique quality is the
ease with which it can be worked, especially
when green. It is suitable for carving,
woodworking, model airplane construction,
and peeling for veneer. As it dries, it becomes
considerably harder, but not as hard as most
domestic woods.
• Good Insulator,
Thermal and electric
— Paulownia wood
has very high heat
insulation properties
(with the thermal
conductivity of the
eight Paulownia
species at 0.063-0.086
Kcal m-1 lu'1 °C'1, one
of the lowest values
for wood).
The Paulownia tree could be
considered the ultimate
environmental tree.
1. Each tree removes 21.7 kg. of carbon
dioxide per day.
2. Each tree releases about 5.9 kg. of
oxygen per day.
3. Each hectare of trees will scrub 32
636.8 kg. of harmful CO2, gases and
dust from the air per year.
4. Each tree can absorb 56.8 liters of
wastewater per day.
5. The large and hairy leaves of Paulownia
play a very useful role in purifying dust
and smoke.
6. Paulownia elongata prevents erosion and enriches the soil with
humus. It has a high tolerance to drought, soil content and temperature
amplitudes (from –20oC to + 40oC), this make the species Paulownia
elongata and its hybrids highly beneficial to environmental recovery.
The tree develops many lateral branches,
thick crown with cluster flowers which
vary in color from creamy to deep violet.
The blossoms last 2-4 weeks then the tree
re-foliates with it's enormous lush and
exotic leaves creating a luxuriant, cool
Summer shade.
PARIS
Central Park
NYC
1. For handicrafts The people in China, Japan and some other countries in
South East Asia have a long tradition of making handicrafts
with Paulownia wood such as flower vases, statue of Buddha
or deities, wooden fish, medal boxes, dressing boxes, TV
and radio boxes etc.
2. For farm implements –
Aquaducts made of Paulownia wood do not subside and
crack, are durable and retain their shape. Threshing tubs of
Paulownia wood are more durable than those of
Cunninghamia lanceolata. People in some provinces and the
dockers in China are very fond of using the poles made of
Paulownia wood.
3. Paulownia wood can also be used to
make blackboards, life rafts, sleds
and surfboards. Paulownia charcoal
can make charcoal crayons, black
powder and fireworks and can also
be used in industries as active
carbon. Paulownia bark can be used
to make dye
4. For house construction –
As the strength of wood is not high, it is not suitable for uses which require
mechanical strength but it is quite widely used for houses. Roof beams and
purlin made of Paulownia wood are light and keep in shape for many years so
they do not put the house out of shape. There is no decay in houses more than
100 years old which are completely made of Paulownia wood. Paulownia wood
is very good for making doors, windows, partition boards, ceilings and inner
roofs due to the woods insulation properties.
5. Fodder –
The leaves and flowers of Paulownia are good fodder for pigs, sheep and
rabbits (Fig. 73). The flower buds, flowers and the leaves of Paulownia contain
fat, sugar and protein. The nitrogen content in Paulownia leaves can be
compared favourably with some leguminous plants.
6. Medicinal uses –
Medicines made of Paulownia leaves, fruits and wood have certain effects on
bronchitis especially on relieving the cough and reducing phlegm. They are
made into tablets and injections.
7. For furniture –
Paulownia is used to manufacture tables and chairs. It is especially suitable for
cases and cupboards which are smoke-proof and are little attacked by insects
8. Musical instruments –
Paulownia wood has good resonance properties
and is often used in making musical instruments.