Yes! Latex balloons are made from latex rubber which is a natural resin that completely biodegrades. They are fully compost-friendly! So those balloons are not that bad for the environment after all.
The latex is produced by many different types of trees after a wound is created in the bark. To harvest the latex a metal tube is inserted into an intentional wound to the rubber tree. The liquid latex runs out of the tree and down the tube into a collection bucket. If many trees are equipped this way, a farmer can produce hundred of gallons of latex in a single day.
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Now you don’t have to be so worried at your next balloon drop or release. Even if some of the balloons end up in an astray, nature will take over and convert the latex into dirt in a compost cycle. Since it’s latex, the balloon will biodegrade.