I was driving behind a railroad MOW truck on the freeway one day, and on a sharp curve at an intersection, a sealed barrel of new spikes flew off the truck and slammed into the guardrail - and exploded spikes. I got off at the next exit and went back, hopped out of my car, put as many of the spikes into the barrel as I could easily grab, and put it in the trunk. I'll have to take a photo of it - the spikes are still in like-new condition, albiet with a fine surface coat of thin rust from sitting in my parent's backyard for a few years (I still lived with them when I got this), but the barrel looks as though it's been used for shotgun practice, as the sharp ends shredded the thin sheet metal.
So if you see a MOW way truck, keep out an eye for loose lading.
Chris