Hard at work! These guys are installing 8ft rolls of Critterfence 1100 poly fence mesh to exclude deer. It's part of a program to regenerate oak and other ground layer plants being devastated by deer:

http://www.csbsju.edu/outdooru/abbeyarboretum/maps/virtualtourboardwalk/8-deer

High strength poly deer fencing is easy to move, repair and take down. It's also safer for deer because they are less likely to get trapped in it; It's more flexible and has a smaller opening size compared to traditional field fence or game fence.