Leaching Bamboo

Storing Bamboo in Water

Storing bamboo in water or "leaching bamboo" is a traditional bamboo preservation method, used by indigenous communities and farmers of several Asian and Latin American regions. In Latin America it has been the tradition to transport Guadua from the mountain and jungle areas towards the urban centers by means of Guadua rafts.

Bamboo Raft (photo: flikcr)

When transporting bamboos over rivers, which generally takes 3 to 4 weeks, the starch content of the poles is subjected to a leaching process that tends to decrease the starch level and increases its durability. Therefore, when arriving at their destination, the bamboo culms are less susceptible to attacks of microorganisms and insects.

This method of immersing bamboo in water is still used today, especially when bamboo needs to be transported from remote areas. It is also recommended for storing bamboo, used in craft and mat applications where pliability is required. However, leaching alone, doesn't guarantee long term protection but it does helps to remove starch and enhances permeability for future treatment by diffusion and pressure treatments.

When storing bamboo in water, a few rules apply:

• When immerging round bamboo, inner nodes should be punctured before leaching. That way, water can run easily true out the bamboo cane.
• Bundle the bamboo culms or splits and store them in running water or tanks.
• When stored in tanks with stagnant water, change the water weekly to prevent growth of bacteria which will cause staining and bad odor.
• Use sinker loads for complete immersion.
• Bamboo can be submerged for variable periods of time, after which they are extracted for their use or further chemical treatment. Without further treatment they should be immersed for at least 3-4 weeks.
• An excessive time in water (after 3 months) causes stains in the epidermis of the bamboo and has the consequence to decrease its physical and mechanical properties.
  

Bamboo Leaching (photo: flikcr)