Here is a link to a picture and schematic of the hole. It is the current 16th hole:
http://www.waltonheath.com/TheCourses/CourseGuideOld.aspx#The hole has been lengthened in modern times, back in the day it was 460 yards. I don't believe there were any trees on this hole back then either.
This is Wethered & Simspon's description, it made their eclectic Ideal Golf Course:
"A fine test of two shots. The tee shot must be long and kept well to the right, as the fairway area that receives the tee shot slopes sharply from right to left. A long second will find the plateau green, well guarded on the right by a bunker and by heather on the left. Visibility quite perfect."
This how Darwin described the hole in his 1910 book. In that book there is also an excellent painting of the hole by Rountree:
"It is the duty of every golf course is to have a good seventeenth hole, and the seventeenth at Walton certainly need not fear comparison even with the Alps and the Stationmaster's Garden. We must begin by hitting a long, straight drive between bunkers on the right and some particularly retentive heather on the left, but that is comparatively speaking, an easy matter. The second shot is the thing--a full shot right home on to a flat green that crowns the top of a sloping bank. To the right the face of the hill is excavated in a deep and terrible bunker, and ball ever so slightly sliced will run into that bunker as sure as fate. To the left there is heather extending almost to the edge of the green, and, in avoiding the right-hand bunker, we may very likely die an even more painful death in the heather."