This photo was taken on August 30, 2010 from Mt. Adams showing the comparison of krummholz on Mt. Madison's south flank over a time span of 43 years. Of course that's not a great deal of time, but there's very little expansion of the balsam fir and black spruce that is detectable from these photos. It looks fairly stable. I've been taking measurements of individual trees, the lengths of branches, diameters of trunks, soil depths, and, where possible, the larger diameters of the clumps of krummholz.
I found this photo of Mt. Madison recently. It was taken from Mt. Adams on August 11, 1967, and it clearly shows the krummholz growth on the upper areas of the south side of Mt. Madison at that time. The hiker is Lilo Heinrich.
The photos above are restricted in that they show one finite area. It would be interesting to have more photos of adjacent areas, particularly the east face of Adams and the west flanks of Jefferson for comparisons.