""Does Texas have an "Adopt a Highway" program?"
Yes, and we have our world famous "Don't mess with Texas" anti-litter campaign.
Funny about the Casey Memorial. There are two types of land in Texas. State land and Private land. Either one would have to be officially dedicated as a memorial to be permanent.
For example i can have a small burial plot on my land, but it would have to remain a burial memorial, and monument in perpetuity.
I doubt the state gave a slice of the bar ditch to the Shehani's. (it would be a senate thing). I also doubt that a private land owner, gave up a chunk. (it's a state surveyor's and title office thing.)
It's a last gasping breath of bs.
Here in Kentucky, families are able to put crosses to mark the site where a loved one perished in a car wreck, but any flowers or wreaths are usually removed in just a couple to days to prevent making a major distraction for other motorists.