We’ve all seen them. Those yellow spots on our hoods and windshields don’t come off especially easily. You can remove them, but sometimes they leave a yellow stain on the paint. So, what are they and why can’t they be washed off?

There are many theories about what that yellow gunk is that clings to cars. Some think it is from airplanes dumping waste in the air. Others wonder if it is some kind of condensation from smog containing a bunch of carcinogens. All we know for sure is that it is some kind of nasty coming down from the sky. Maybe aliens? 

What are those yellow spots on our car paint?

Actually, it’s pollen, from bees. At least that’s what the California AQMD has determined, according to the LA Times. But beyond that, there is a more definitive, disgusting answer. According to Susan Cobey at the UC Davis bee laboratory, it’s digested pollen, or more precisely, bee poop. 

The small yellow blobs you see are a combination of pollen and flower nectar. This nectar contains a lot of glucose and fructose sugars. These all get mixed together inside of the bee and then are regurgitated inside of the hive. That’s what honey really is, bee vomit. 

So that also gets pooped out. The sugar and pollen harden, and stick to almost any surface, especially flat surfaces like the paint hoods and trunks, which is probably where you see it the most. 

Why is there so much bee poop on my car?

Flying back and forth from the hive, bees follow a general traffic route. If your car happens to be under one of these routes, it’s going to get pooped on. According to Cobey, it is especially likely in the spring and summer.  

The yellow droppings are known to be acidic, so that’s not good for the finish of your car. Clawing or scratching them off is not a good idea unless you absolutely don’t care about protecting your car’s clear coat. But if that’s the case, why bother trying to remove it?

The good news is that as bee populations are dying from mites and the effects of climate change, finding these yellow spots on your car is a good thing. It means there are active bee colonies in the area you park your car. It also means there is little you can do about it. 

How do you remove bee poop from your paint?

You can try parking your car in another spot. Especially if you have an enclosure or garage, that’s the best place to park. The other would be to use a car cover to protect the finish.

Removing it entails using lots of soap, water, and patience, to loosen the gunk enough to wash it away. As hardened sugar takes a while to melt in our mouths, so too does it take a bit of time for the spots to melt away. Keeping your car waxed is also important, especially for light- and dark-colored vehicles. The spots just seem to pop more on lighter and darker surfaces.