My husband and I were heading out for a final goodbye dinner before the two of us embarked on trips to separate countries when I first noticed a little green leaf on Google Maps navigation. It popped up next to my time remaining indicator and remained there during the whole of our (very brief) trip. I took a screenshot of it and wondered aloud what it was. If you’ve seen it, too, then here’s what it means.

Common sense tells you that a green leaf probably signals something to do with eco-friendliness, and that’s pretty much exactly what’s going on here.

Google Maps calls it the “fuel-efficient” route. It calculates a route that includes the least traffic, the least hills, and more constant speeds. All that combines to save you fuel, since you can mostly just coast to your destination.

If you want to turn it off, start your navigation to your destination. Go into the settings, and under “Route Options,” where you’d normally toggle things like avoiding highways or tolls, you’ll see a toggle labeled as “Prefer fuel-efficient routes.” If you’ve just had an update on the app, it’s likely that this toggle is turned on.

Do note, though, that you might still see the green leaf: Google automatically takes you on the most fuel efficient route it it’s the fastest route, and it’ll likely label it as fuel efficient. On the trip to the restaurant that I took, I was perplexed by the leaf label in large part because it’s the route I usually take, and the only reason I turn on navigation now is because there’s been rotating construction on the side roads near the restaurant. I’m glad I did, though, or I might have missed this neat new update.

This isn’t the only update that Google has introduced: it will also now alert you to low-emission zones in the United Kingdom, France, Germany, the Netherlands, and Spain. These are zones where only vehicles with a certain emissions standard are allowed to enter — definitely something you want to know before you arrive there.