Survey crew or wetlands delineation most likely.

Ask the landowner, I' ve seen people mark the trees they want cut down like that (except for the bolt in the ground)

Lance

Are they getting ready to cut some timber?

Well I believe the deer are planning putting up a building. You better kill them before the build their building. I will agree with everyone else it is a Surveying crew.

Whatever it is, or whoever did it, the bolt in the ground is the real marker for whatever they are doing, and the tape in the tree is just there to help them find the bolt.
Beyond that, I' d say keep an eye on those deer. I think DH1224 may have a point.

Were all of the trees marked pines? If they were then you are probably right about the forestry service. The Southern Pine Beetle it a huge problem here in the south, and they are trying to control it. They would not mark dead trees because the preditors of the southern pine beetle live in the trees after the tree is dead. It would mark either trees that have some brown needles or that are near infested trees. Another possibility is that it could be workers from a paper company, or some other company that depends on pine trees. The paper companies hate the SPB more than anyone because they leave black rings in the wood of the tree, and that makes it harder to process the wood for paper. I hope that helps things a little. Of course it could be something totally different, but I would think that it would be something along those lines.

It' s got to be surveyors. They cut the trees to shoot the line. The pin in the ground with the orange tape is a reference point that they set up on. Ask the landowner, Im sure they' ll know. Maybe they are subdividing or something.

foresters will mark out an area such as you mentioned when there is a beetle infestation. they essentially cut out a quarantine area to prevent infestation of the rest of the timber.

Some times in order to survey someone else' s property they have to get a bench mark or starting point (a recent known fixed position) which may be miles away in remote areas. They will shoot the elevations and put a pin in the ground, mark it and continue on till their final destination. They should ask permission to do this but might have just gone ahead without. They have to trim the branches in the way to look through the transit ( like a telescope).