Something strange is appearing under the streetlights in the American West. Dr. Shannon Murphy, an ecologist, was walking his dog down an alleyway in Denver, Colorado when he noticed an invasive cheatgrass colony breeding under streetlights. She had already grown prairie grasses in artificially lit greenhouses to study how moths interacted with plants, but cheatgrass thrives under the light. On the other hand, I was surprised to see no benefit to native grasses.

This prompted a team of researchers to survey Denver alleyways and found that cheat grass was three times more likely to grow under streetlights than in unlit areas or near unlit utility poles. understood. While it may explain why cheatgrass is thriving in many other major urban areas, how streetlights gave the plant a boost has baffled scientists.

Cheatgrass is an invasive species that has invaded the western United States, displacing native grasses and threatening farms. It also poses a fire threat as it is an annual that dies in late spring, leaving dry vegetation like a crater box that fuels wildfires.

Cheatgrass can recover quickly after such a fire, helping it to outcompete perennial native grasses that regenerate much more slowly. It spreads rapidly.