St George Dinosaur Discovery Site at Johnson Farm
I enjoyed visiting the Johnson Farm Dinosaur Walkway, which displays some of the oldest and best-preserved tracks in the world. Dinosaur tracks were discovered on the farm in February, 2000, and it has become quite an attraction. The site is in the early stages of scientific study - so far over 1,000 tracks have been found within a 10-acre area. Most were made by Dilophosaurus-like creatures and are three-toed, 13-18 inches long. There are also some smaller tracks and researchers have identified skin prints and impressions made by tail drags and swimming movements.
The tracks were found in large slabs of sandstone from the Moenave Formation, dating back some 205 million years to the beginning of the dinosaur era. I've tromped over that very sandstone for years, never realizing it sheltered such treasures. Nobody knew, until Dr. Sheldon Johnson flipped over a slab while trying to level his land. There, on the underside, the tracks were clearly visible.
Most of the tracks are actually "negative impression" casts, which appear as bumps on the stone. The area was the bottom of an ancient freshwater lake in the center of the super-continent Pangea. Footprints left in the mud filled with silt and sand, and more sand was deposited over the top. The mixture eventually solidified into sandstone and mudstone, forming the casts. Now, when the slabs are flipped over, the casts appear, much like Jell-O popping out of a mold.
The casts are relatively soft and would have eroded quickly if left exposed. Dr. Johnson donated his land to the city of St. George, and the U.S. Congress recently appropriated funds to help construct a science and visitor center.
Volunteers do most of the work at the site. To volunteer, or to schedule a large group visit, call St. George Leisure Services (435-574-DINO).
The site is easy to find. Exit 10 from I-15 will put you on 3050 East (Pineview Drive). Follow it south until it swings to the southwest and becomes Riverside Drive. Just continue driving until you reach the site (2200 East Riverside Drive), which is marked by a sign.
The Dinosaur Walkway is just minutes from downtown St. Goerge. Visits can range from one to several hours, depending on your level of interest.