I remembered my childhood in southern Kazakhstan. The plant grew in the steppe - they called it simply - the milk. What it is, I do not know. The essence of what - the cuts were made on the trunk - the milk was separated. In the sun, 30 degrees became brown. Next - chewing, splashing the sand, there is a real chewing gum, first bitter, then quite acceptable.
In Russia, they said, they did this from berry bark. The bark was broken into layers and thrown into the boiler. Standing on fire. (I did not try it), they said, it was the same chewing gum.
Who knows such ways? And from what?

yyy: walked around the house in the summer, and gathered the hot bitum from the asphalt )), the asphalt then splashed out, and the gum was obtained )) true)) and the plasticine from the freezer was chewed, and the window patch ))))here childhood was happy)))

And we, the Sibirians, also chewed the sulfur (so they called the resin of the larvae). If you chew it, you get brown gum (outside, except the color, you can't distinguish from the usual), delicious and terribly useful :)))