Does this constitute a "pest"?

only if you intend to drive the vehicle again. LOL How long did it tie to get to this stage? I hope you get the villain. 

I've seen an attic stacked with pine cones like that. Thousands of baseball sized pine cones. Squirrels...squirrel away stuff for lean times.

Are you asking if the nuts are a pest..... or the vermin that put them there?

maybe or maybe not .. animals taking over things people ignore for months or years doesnt really make them a pest, pretty natural acually .. if its chewing up your daily driver or house wiring now thats a different story lol ...

Wasn't this posted like a month ago?

In the animal world any one that does damage or a threat. If its damage to home or property best to call the local conservation authorities and let it be known first because some could be out of season. In my case I was told to kill all the raccoon opossum and skunk, plus living in mid Missouri my 60+years only the last few years there’s more and more armadillo climate? But I ended up shooting 26 raccoons 6 opossums 3 skunks and 2 armadillo, and I had to report my total kill . They told me that when I trapped them don’t move them to another location because they are having more than two and three litters a year more than normal. But just be sure to cover your ass ! Good luck 

I sold an old car to my land lord who ran a used car lot. Told him the brake lights were out. He let some gal drive it and got rear ended. A bunch of acorns fell out from under the dash. He said he probably should have fixed those brake lights.

Shoot, shovel and shut up..... not advocating anything...... but the "triple S" approach has served many for a lonnnnnnggggg time

But will say to take a long ahrd look around before embarking on that line of work.....

I had an ATV in a shed last year that I had to have serviced because mice had adopted it as a home, chewed a bunch of stuff and filled the interior areas with acorns. The service guys thought it was hilarious, they gave me a big box of the acorns they pulled out off it. 

If you will leave the hood partially open it helps with that, assuming it is not a daily driver