If you’re like us, watching this video will leave you with many questions, chief among them: What on earth is going on?

The footage, filmed in Spain and posted to Twitter by user Kyle Hill, appears to show the grass of a public park alight and burning at an alarmingly fast rate. The thing is, as the line of fire moves across the green, the grass, picnic tables, and trees remain unharmed. There appears to be a white film atop the grass that is actually doing the burning, and once it’s gone, the fire moves on.

That white film is poplar fluff — poplar seeds that are produced by the female trees — collected en masse atop the grass. Watch the video below, with particular attention to the grass:

Some commenters claim that what is burning is pollen, not poplar seeds. Snopes, the internet’s definitive fact-checking resource, reports that it is indeed poplar fluff being burnt but that there’s no indication as to whether or not the event was a controlled burn.

Poplar fluff is not related to allergies as male poplar trees are the ones creating the pollen, but the fluff can be a contributor to the spread of wildfires.

Regardless, the rapid burn that spares everything but the fluff is interesting to watch, and just the type of distraction we needed right now.