Vertical Soak Diffussion
for Bamboo Conservation

Environmental
Bamboo Foundation

*Note: This excellent document is converted from a PDF document
from the www.bamboocentral.org website. This was done due to the
PDF causing my PC to hang and space issues. For the complete
and exceptional PDF document please visit there website.
No information has been altered.

The Environmental Bamboo Foundation (EBF) is an Indonesian non-profit
organization started in 1993 by designer and environmentalist,
LINDA GARLAND.

The EBF strives to protect tropical forests by promoting and demonstrating the
many conservation and development opportunities that bamboo offers. The
mission of the Environmental Bamboo Foundation is to encourage, through
research and education, the sustainable planting and utilization of bamboo in
an effort to promote its many environmental benefits and protect the world's
remaining tropical forests and mangroves.

Based in Bali, Indonesia, the EBF has affiliate non-profit organizations in the
United States and in Holland

Acknowledgements

Initial research on modified Boucherie Teatment was done by 
Prof. Dr. W. Liese, Universität Hamburg, Germany, and later 
adapted by the Environmental  Bamboo Foundation with Don Longuevan 
under a grant from IESC International Executives Service Corp.  
Laboratory testing was performed by Koppers-Hickson in New Zealand.

We thank Ben Brown of Mangrove Action Project for providing valuable 
help and insight during the testing period and providing translation services 
for the Indonesian edition.

We appreciate the advise/comments made by Prof.Liese along the 
development of the VSD treatment.

Many thanks to Emerald Starr of Sacred Mountain Sanctuary in Sideman, 
Bali, who used a high percentage of experimental VSD treated bamboo 
timbers when building his resort. Seven years later, the bamboo he used 
is still in excellent condition.

Research & Development:	Environmental Bamboo Foundation (EBF)
Graphics & Layout:	Studio LaBel, Hedi LaBel
Engineering Consultant:	Ben Brown
Editorial Assistant:	Petra Schneider
Project Manager:	Ketut Sadia

This publication is not copyrighted. EBF encourages the translation, 
adaptation and copying of materials for non-commercial use, providing 
an acknowledgement to EBF.

Every effort has been made to ensure that all the information in this booklet 
is accurate. However, due to differing conditions, kind and age of the 
bamboos, tools, and individual skills, the publisher cannot be responsible 
for any injuries, losses, and other damages that may result from the use 
of the information of this booklet

First Edition published 2-1-2003 by:
LINDA GARLAND
Environmental Bamboo Foundation, Bali, Indonesia,
ebf@bamboocentral.info, www.bamboocentral.org

Table of Contents

1.  Preface

2.  Introduction

3.  Managing Bamboo

4.  Harvesting Bamboo
	4.1 The Powderpost Beetle

5. Planning a Treatment Center
	5.1 Elevation View
	5.2 Floor Pan

6.  Tools and Materials

7. Mixing the Borax Solution

8. Information about Borates
               8.1 Reuse Guidelines
                8.2 Disposal Guidelines
                8.3 Where to buy BORATES in Indonesia

Preface

The use of bamboo products requires often its protection against
biodegradation by chemical treatment. Its application is hindered
by the structure of the culm, the need for larger technical installations
and the danger of environmental side-effects. The VSD method
developed by EBF is obviously an efficient method to obtain well
treated culms, safe to be handled. Its wider application, also to
other species, will strengthen its base.

Walter Liese
Universität Hamburg, Germany

Introduction


Bamboo culms are a natural material susceptible to insect and
fungal attack. Without treatment products made from bamboo can
be expected to last for only up to 3 years.
There are many different techniques for curing and treating bamboo
culms in order to prevent splitting, insect infection and fungal growth.

In this booklet we present the Vertical Soak Diffusion (VSD) method which 
uses minimally toxic borates as preservatives. The method
has been tested in Indonesia using three species of bamboo:
Dendrocalamus asper*
Gigantochloa apus*
Gigantochloa atter*
If you are intending to use other species of bamboo, follow the
methodology in this booklet to treat a small section (1-2 internodes)
and observe the rate of penetration of the red dye discussed in
step 14, page 18


Whereas bamboo treated by the modified boucherie system (a pressure 
system introduced by Prof. Dr. Liese, Hamburg, Germany) is 
appropriate for large scale plantations growing bamboo for 
construction timber, furniture, and some crafts the VSD system 
works well with small-plantation situations , and community development 
work in rural villages.

Managing Bamboo

Clumping bamboos are non-
invasive. They do not ruin
buildings, they grow very fast
when young and the culms
are larger than those of the
running bamboo. They require
little maintenance, although
simple clump management
will benefit both the grower
and the bamboos.

In the dry season, almost all
culms that are 3 years or older
can be removed from a clump
by cutting them just above a
node about 20cm above the
ground. Some younger ones
have to remain for further
nourishment of the rhizome.

In the shooting season, remove
any shoots that are going to create
overcrowding (many species are
edible, cooked). Leave only the
shoots of good diameter which
have potential to produce straight
strong poles for timber use.

Harvesting Bamboo


Wet Season	Dry Season

Harvest Bamboo during dry season

The best season for harvesting is after the rainy season when
starch content in the bamboo sap is low. Starch is the favourite
food for pests. Don't harvest during shooting season! Cut bamboo
that is 3-5 years old. Bamboo older than 5 years is harder and
the inner culm wall becomes impermeable to the BORAX BORIC
ACID Solution.

There are 2 different ways to tell the age of bamboo culms:

1) Mostly, culms at the inside of a clump are the oldest.

2) Label the new shoots, this is the safest method.

The culms should be treated
soon after having been cut,
but can be left for a few
days standing upright,
placed on a stone. Due to
the ongoing transpiration
by the leaves the culm will
loose some of its moisture
and also starch, which is
the food for the pest, i.e.
the Powderpost Beetle.
But don't wait too long,
since moisture is required
for the following diffusion
process.

The Powderpost Beetle

Stored bamboo is
endangered by beetle
infestation which can be
recognized in the form of a
talcum-like powder and
small holes in the area of
the nodes and along the
internodes.

Planning a Treatment Center

Floor Pan

Elevation View

Floor plan Treatment Area

Tools and Materials

Eye Protection		Hacksaw
Rubber Gloves		Iron Rod with hex Nut
Rubber Boots		Bamboo Stick for Stirring
Boric Acid		Pump
Plastic Containers Mixing & Measuring		Small Sum pump
Red Textile Dye Aniline		Rubber Hose
Water		Node Punch
Filter		Hydrometer
Containers For Solution		Brushes for cleaning
Rope (for tying culms)

Mixing the Borax Solution

STEP 1

Calculate the internal volume of the culms.
There are 3 differrent ways to do this:

1. Volume in liters = inner radius squared x 3.1416 x height in cm of
     culm divided by 1000.

      Example: bamboo with radius = 6cm, height = 400cm
          ((6x6) x 3.1416 x 400)) / 1000 = 45 liters

2. Fill one punctured culm with water and simply measure how
many liters it takes to fill it up. Multiply by the number of culms.

3. Fill one average internode; measure the amount in liters and
multiply by the number internodes and by the number of culms.

STEP 2

Mix 3 kg of BORAX with 2 kg of BORIC ACID and add 45 liters water. This
gives a 9 to 1 or 10% solution

Borax 3kg Boric Acid 2kg

Water 45 litres
1.5 litres each

STEP 3

Add red analyn textile dye. It should completely penetrate the tissue of the culms from the inside all the way to the outside skin. If the particles of the dye are too large they will only partially dissolve and "plug" the openings in the tissue thus preventing penetration of the preservative.

STEP 4

Slowly add water stirring constantly until BORAX/BORIC ACID and dye are completely dissolved and no more crystals are at bottom of container.

STEP 5

Test the solution with a hydrometer under normal temperatures of your region.

Fill a small test container with the Borax/Boric Acid solution slowly, so as to not form air bubbles. Lower the Hydrometer into the container and give it a quick twirl like spinning the top.

This will get rid of air bubbles that might have accumulated on the hydrometer.

Then read the number where the solution crosses the scale on the hydrometer, like reading a thermometer: 1.035 (or whatever a close number is) will be your benchmark for re-testing the solution later.

STEP 6

Thoroughly clean the outside of the bamboo
culms with water and brushes (or coconut husks
and sand, or scotch brite)

STEP 7

Weld hex nut to one end of iron rod. With this rod you can punch holes through the diaphragms.

The hex nut will create large diameter holes thus preventing air bubbles from forming in the culms during the filling procedure.

STEP 8

Place the bamboo against a
wall. Insert the iron rod and
punch holes through the nodes. Make sure the last node is not punctured.

STEP 9

Move the bamboo to the
concrete basin. Stand up vertically. Tie culms securely together so that they cannot move when they are being filled with the BORAX/BORIC ACID SOLUTION. Culms become very heavy when filled.

STEP 10

Connect a hose to the
container which holds the mixture. Pump the solution into the culms.

STEP 11

Fill the entire bamboo with the solution. Every morning refill the culms which have
absorbed approximately 1% of the liquid overnight. Every day absorption rate is less.

STEP 12

On Day 13 don't add more solution.
Allow the level to go down to avoid
overflow when the last node is broken.

STEP 13

On Day 14, test check the
culm by sawing off the
upper internode. The fabric dye has now penetrated the culm walls sideways and coloured them pinkish. Carefully carry the filled culm close to the sump hole and break the last node using a metal punch. Make sure you wear face protection. The diaphragms of large culms should be punctured by using the iron rod. The solution will now flow on the sloped basin floor into the sump hole.

STEP 14

Leave the bamboo for a minimum of one hour in the basin for the solution to fully drain out of culms into the sump hole. Pump leftover solution back into container through a filter for re-use. The filter should be regularly changed. Test again with the hydro meter and add more BORAX/BORIC ACID if necessary (see appendix page 23). Wipe down the whole culm to remove excess borate.

STEP 15

Store the bamboo horizontally or vertically in the shade (hot sun splits it) to slowly dry. Make sure that it is not exposed to rain which could wash out the preservative.

Information about Borates

BORAX/BORIC ACID is more environmentally friendly than other wood preservatives currently used.

Reuse Guidelines

The BORAX/BORIC ACID SOLUTION can be used more than once for treating bamboo, as long as the hydrometer reading of the solution is still at the initial level, of approximately 1.035.

Keep in mind that, as the bamboo sap gets partially drained out of the culm, the starch/sugar from the sap will move into the treatment solution. This can lead to inaccurate hydrometer readings. After the 3rd or 4th use gradually increase the BORAX/BORIC ACID concentration to 1.040 and 1.050.

At the point when the drained solution foams significantly and/or mold is forming on the surface of the solution and on the bamboo culm it is time for the solution to be disposed of.

Disposal Guidelines

BORAX/BORIC ACID is non toxic to the environment, but is highly saline.

When a moderate amount of it is absorbed into the ground, the ground filters out the salt to the point where it does not pollute the ground water. However, it is advisable to dispose of it safely and out of reach of children. When diluted with more water the discarded solution could be used as a herbicide on terraces and walkways.

Where to buy BORATES in Indonesia

PT CHIMIFIN JAYA UTAMA, JAKARTA
Tel 021-424-0202, 424-7141, 425-5563
Fax 420-5588

UD. Saba Kimia, Denpasar,
Tel/Fax 0361-410662