I passed several rubber tree plantations on my drive from Phnom Penh to Mondulkiri in Cambodia. The trees are planted in very neat rows, creating excellent horizontal, vertical, and diagonal lines as you stand among them and look around.

To collect the rubber, diagonal slices are cut into the trees and the rubber/sap drains into bowls that are placed on the trunks. The diagonal slices also cause the trees to develop a slight, pleasant bow. 

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