RV Fungus Among Us

While camping at my brother’s farm in the middle of Michigan, we noticed some dark brown spots on the exterior of our fifth wheel that we hadn’t seen before. I was able to rub some off, so we didn’t think much about them. But we were curious as to their origin. 

We hadn’t painted or diffused anything nearby. Had my brother sprayed some pesticide or mosquito repellant? A quick browser search indicated we were dealing with fly defecation. Situated across the street from a cow farm, we had observed a number of flies in the area, so we quickly dismissed the dots as that. 

Shooting Spores

Fast-forward two months. After setting up our rig for a long-term winter stay in the Southwest, we paid someone to power-wash it. He finished cleaning the coach’s exterior, but the spots remained. It appeared we had wasted $250.

Further research revealed we were actually facing a case of artillery fungus, which is commonly found on rotting wood in moist environments. Having been established in 1893, the Michigan farm had its fair share of decaying wood piles, especially after a heavy windstorm wreaked havoc on the property earlier in the year. 

The name of the fungus is derived from its ability to release, or shoot, sticky spores into the air that attach to things such as vehicles up to 10 feet away. Those spores, if left untreated, can become permanent fixtures. 

Not wanting Tagalong to be speckled with brown spots for the rest of his life, we decided we’d better do something about them. But what? They clearly didn’t come off with power washing, which included soap and water. We needed a stronger substance. 

Finding a Heavy-Duty Solution

Having spent a decade working on WWII airplanes, Bob is familiar with a variety of heavy-duty cleansers. His favorite is called Awesome, an all-purpose cleaner we’ve only been able to find at Dollar Tree. Evidently, it’s also available on Amazon (paid link). 

Knowing Awesome did a good job of removing grease and grime from airplane exteriors, Bob decided to try it on the RV spots. Simple rubbing of the cleanser didn’t immediately erase them. So, he invested in a polisher and put that to work with the Awesome. That extra power did the trick, allowing Bob to scrub the dots away.

The only problem with this heavy-duty cleaner is that it can strip away wax and protective coatings. And that’s exactly what it did to our rig. In addition to removing the brown spots from Tagalong, we effectively rubbed away any protectant, a must-have in the harsh Arizona sun. 

Investing Elbow Grease and Time

That meant we had twice the job we thought we did. With rain in the forecast, we spent our free time dousing, rubbing, and scrubbing Tagalong’s exterior to clean all the spots and Awesome off and reseal it with Turtle Wax ceramic spray coating (paid link). 

On a 42-foot trailer that stands more than 13 feet tall, that’s no easy feat. It involved a lot of early mornings to beat the heat and a lot of ascending and descending our telescoping ladder, moving it, and repeating the process — for the better part of a week. 

Afterward, we discovered a few spores we missed. Those will have to linger — and maybe even become permanent. But we’re confident our rig is clean and protected. And maybe next year, we’ll do the full job ourselves and not waste money on a middleman. 

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