https://www.youtube.com/watch?v=ZIH0GugIH9c
Nice short video and to the point.
Those same cedars are an issue in other states as well, Nebraska is full of them and an area I hunted that was filthy with birds one particular property was loaded with them and the birds were rarely there.
New Mexico has salt cedar all along the Rio Grande and it is a major issue, those trees are sucking up all the water as well as choking out other native plants, there are some projects on Dept. of Rec. land where they are trying to eliminate them.
Looks like there using some sort of grinder attachment on a, forestry grinder I think they call it?