What is that green turf material on the side of the road?

I am not certain what the material you are referring to, but I have seen stuff like this sprayed out. in a liquid form and applied to barren areas. Yes, it does have grass seeds in it, and the green stuff is made to provide a moist medium for the seeds to germinate. It may also contain fertilizer. Perhaps they put the green color to help it blend in. Imagine the public reaction if they had put in hot pink color, or left it white!

It’s hydroseeding.

It’s called erosion-control blanket. It’s typically applied over the hydro-seeding process that @snowberry described, which actually lays down the seed/fertilizer mixture. On embankments, though, rain would soon erode that loose material away. The blanket is a mat of shredded wood (excelsior)held together by a bio-degradable netting that holds everything in place and provides a mulching layer to retain moisture. The grass seed underneath just grows right through it and the blanket eventually biodegrades.

Yes, it’s hydroseeding. Or, erosion control like @thorninmud mentioned.
Mixing grass or wildflower seed with fertilizer in a tacky, toilet paper kinda “filler” material that retains moisture and prevents the seed from being washed away until it establishes itself.

I used hydroseeding for a new lawn once, it was really cool and took beautifully.

@Coloma Is it expensive? edit – I have a prime spot in my front yard that refuses to grow. We recently removed rocks that had been preventing growth for a decade.

@silverfly

I don’t know what the prices are today, I did mine about 15 years ago, and I think it was around $300, but, honestly I don’t remember.
They charge by the sq. foot usually, you’ll have to check around with local hydroseeding companies in your area. :-)

Okay, cool.

Hydroseeding is more expensive than regular seeding, but less expensive than sodding, if I remember correctly. (I worked for lawn and landscaping companies for many years.)