The height attained by the trees of this fossil forest can not be ascertained with certainty, since the tallest trunk now standing is only about 30 feet high, but every one observed is obviously broken off, and does not show even the presence of limbs. Perhaps the nearest approach to a measure of the height is afforded by a trunk (shown in [fig. 10]) that happened to have been prostrated before fossilization. This trunk, which is 4 feet in diameter, is exposed for a length of about 40 feet, and as it shows no apparent diminution in size within this distance it is safe to assume that the tree could hardly have been less than 100 feet high and very probably may have been higher. This trunk is wonderfully preserved. As may be seen from the illustration, it has broken up by splitting along the grain of the wood into great numbers of little pieces, which closely resemble pieces of “kindling wood” split from a clear-grained block. In fact, at a distance of a few yards it would be impossible to distinguish this fossil “kindling wood” from that split from a living tree.

Fig. 10.—Prostrate trunk of fossil redwood, Specimen Ridge fossil forest.

The large redwood trunk already mentioned ([title-page]) as being nearly 10 feet in diameter may be compared with its living relative of the Pacific coast in order to calculate its probable height. The living redwood is usually 10 to 15 feet in diameter and ranges in height from 200 to 310 feet, and as the two are so very closely related there is no reason to suppose that the fossil trunk was of less height, but by a moderate estimate it may be accredited with a minimum height of 200 feet.

MAP OF YELLOWSTONE NATIONAL PARK
Norris O Denotes Ranger Station
←Direction of Travel
Distances given are between main points by road
NOTE THE MILE-POST SIGNS

[High-resolution Version]

TOWER FALLS.

The most accessible fossil forest, marked "Petrified Trees" on the map, is west of the Tower Falls Ranger Station and Camp Roosevelt on the road from the Grand Canyon to Mammoth Hot Springs, by way of Mount Washburn. It is on the middle slope of a hill that rises about 1,000 feet above the little valley and may be reached by a branch road from the main loop road. As the traveler approaches the forest he will observe a number of trunks standing upright among the stumps and trunks of living trees, and so much resembling them that a near view is necessary to convince him that they are really fossil trunks. Only two rise to a considerable height above the surface. The larger one is about 15 feet high and 13 feet in circumference ([fig. 11]): the other is a little smaller. As the roots are not exposed, it is impossible to determine the position of the part in view or the original diameter of the trees, as the bark is nowhere preserved.