I’d say coral pieces or bryzoans

This rock is limestone which forms mostly in marine settings so it would not be grass. They looks more like burrows to me. They could be tension fractures but they are not oriented well if they are.

Thank you for commenting and helping me identify this. A little context might help. It was found in Pocomoonshine lake in Princeton, Maine. A rather shallow lake. There is a ton of it in there. When you break it, pieces of grass like stuff comes out. I have absolutely zero knowledge of geology, so any help is appreciated.

Probably bryzoans, grass wouldn’t be found in such quantities in water

Asbestos can be in strands?

Researching reveals that there are large deposits of asbestos in Maine. “Maine has numerous natural asbestos deposits, as well as a large number of industries, that potentially exposed their workers to the toxin. From 1999-2015, 381 Maine residents died from mesothelioma Maine suffers the highest mesothelioma mortality rate in the country with…[Read more]