The name for the Kabok tree (Ceiba pentandra) in Khmer is "Koh", a word which also means mute. During the Pol Pot era, an oft repeated saying had it that "if you want to live, grow a Koh tree in front of your house." Part official threat, part unofficial advice, this saying was directed at the "new people" or "17th of April people" (i.e., those who fled from the cities to the countryside in April 1975). The saying invited the addressed to remain silent about everything that they had seen, heard, knew, or felt.

As Phy Chan Than explains it: "At the center of my canvas, I have painted the trunk of a Koh tree which stands for all the people who lived under the regime of Pol Pot. The areas on each side of the trunk represent the savagery and threats of that time. Two circular forms on the upper right and the middle left represent how Cambodia was as separate as another planet from the rest of the world then. Although we had been members of the international community, during the Pol Pot regime no country came forward to help us in any way." The colors on either side of the Koh tree attempt to represent the two different tactics used by Angkar (the leaders of the Pol Pot regime). The red side represents the "use of terrible acts when someone did something wrong or when they forced us to work." The green side, on the other hand, represents, the hopeful, encouraging words which "Angkar used during meetings or when they coaxed us to do something." A red river runs across the middle of the canvas and flows over the trunk of the Koh tree recalling the later slogan used in the early 1980s to describe the Pol Pot era as a time when "the tears and the blood of the Khmer ran like a river, and their bones made mountains." At the bottom, gouging into the trunk of the Koh tree, is "a hole which Angkar dug in order to try to uproot the Koh tree which stands for the people of the 17th of April." "They were constantly trying to kill or uproot us," Phy Chan Than explains, "we had no value to them." The trunk of the Koh tree itself is fractured in several places "to show the scars which all the survivors still bear today both inside their bodies and in their hearts."