"The Plant" was introduced to the peninsula by the U.S. Army, to stabilize the dunes at Fort Ord. I believe it's African in origin. There are several types of ice plant, but the type that was on Spy's opening holes, was of the large phallic looking leaf type. The plant was so prolific, I've seen it growing in Hollister, some 30 or 40 miles inland. There's a smaller leaf version planted on the coast in Pacific Grove (near the Seven Gables Inn) that blooms the most beautiful purple majesty, in the early spring.
A strong creative golfer, with enough experience, can play shots out of the stuff, if their lie isn't buried too deep, under a thick mat of the stuff. Explosion type shots always worked best for me.
Back, before Mike Strantz's work at MPCC, the old Shore course had acres and acres of the stuff, lining their coastal holes. It's presence amplified the need to be accurate. Perhaps it was a bit disproportional of a penalty, due to the exposed nature, and orientation to the coast, of those holes. While the corridors were ample, when the wind would kick up, ample, left the building.
As for the 4th at Spy, I say good riddance to the stuff. I recall seeing it being slowly killed off, when it took on an orangish hue. That was it's most beautiful.
If I could, I would plant 6.93 acres of the smaller leaf variety at my house. That stuff is that cool and maintenance free. I doubt it would survive, and, due to it's prolific nature, I suspect it wouldn't be good stewardship.
Ally, Spy opened in 1966. The U. S. military presence on the peninsula dates to something like 1903