The marshy area is usually played as casual water when needed. Otherwise, it is bog-like. You can play out of it, but you almost need to play it like a fairway bunker to prevent hitting fat. They have another area like this right where the "earth" is in the lower right of the picture.
My concern was really the forest area being designated a lateral hazard improperly. There may be a small creek that runs just inside the tree line, but it is dry most of the time. There was discussion in the Divot GUR thread about improperly marked lateral hazards.
BTW, I hate this hole. In addition to the odd landing area, the green is the worst saddle-back green I have ever seen. There are only two small, maybe 50 sq ft areas on the green that are less than 4% grade. The green also slopes away and to the right of the fairway, so getting a GIR is very difficult. You need to hit the very middle-left of the green to hope to stay on and not pitch off right and long. Usually, I am trying to get an up&down to par.
I have never parred this hole (the only one on the course). From the back tees, it is a driver for me to try to get the 150 marker (220 yards). If I get roll out, it goes long and down a slope to the cart part. If I use a 3w or 3h, my approach shot could be 180+. Any fade off the tee gives you a long second shot. A hook into the marshy area may get you blocked out due to the trees.