Eccentric growth rings and reaction wood in tree cores and multiple generations of asphalt patching on Delhi Pike are evidence that the thick landslide began to form at the head and enlarged progressively. The position of the uppermost cracks in the head roughly coincides with the boundary between cut and fill in the roadbed. The abrupt movement that occurred in 1958-59 apparently extended only a few meters downslope from the cracks in the road to a complex of toes. The house and other structures on the property were destroyed by another episode of abrupt movement in 1973. Presumably, new failure surfaces formed that successively emerged farther down the slope in 1973 and later. Movement appeared to be continuing in 1990 on at least the deepest
of these surfaces, which emerged as a bump in new asphalt on Hillside Avenue.