Beekeepers in the Alsatian town of Ribeauvillé can now stump you with a riddle based on actual events: What’s black and yellow, and produces something blue or green?

Local bees keeping a regular diet of waste from a bio-gas plant have produced batches of blue and green honey, much to the anxiety of honey producers who already face supply issues due to the decline in bee population worldwide.

The Agrivolar plant processes waste from a Mars factory, which makes colored M&M’s. Underestimating the pull of candy-coated, melt-in-your-mouth-not-in-your-hands goodness, Agrivolar left the waste in open containers. Naturally, the bees started dining on rainbow colors, which led to honey pots sporting the hues of a throwback Timberwolves jersey.

The plant has reportedly addressed the issue by keeping the waste indoors and in closed containers.

[via Russia Today]