A FOREST OF STONE 



By F. H. Knowlton, United States Geological Survey 



REMARKABLE fossil forests exist trees, but so far as known none of these 

 in Yellowstone Park, the most are equal to the fossil forest on the 

 remarkable, it is believed, of the slopes of Specimen Ridge, 

 several fossil forests which have The fossil forests are easily reached 

 been discovered — there are others in over the wagon road from the Mam- 

 Egypt, in California and in Arizona — moth Hot Springs, or from the Wylies 

 because in the Yellowstone most of the Camp at Tower Falls, and they are in 

 trees were entombed in their original their way quite as wonderful and worthy 

 upright position and not found recum- of attention as many of the other fea- 

 bent and scattered about the ground, tures for which the Yellowstone Na- 

 In Arizona, for instance, the fossilized tional Park is so justly celebrated. 

 trunks have evidently been carried a Recently another extensive fossil for- 

 long distance from where they origi- est has been found on the divide between 

 nally grew. In the Yellowstone the trees the Gallatin and Yellowstone Rivers in 

 now stand where they grew, and where the Gallatin Range of mountains, in 

 they were entombed by the outpouring Park and Gallatin Coimties, Mont, 

 of various volcanic materials. Now as This forest, which lies just outside the 

 the softer rock surrounding them is boundary of the Yellowstone National 

 gradually worn away they are left Park, is said to cover 35,000 acres and 

 standing erect on the steep hillsides, to contain some wonderfully well pre- 

 just as they stood when they were liv- served upright trunks, many of them 

 ing; in fact, it is difficult at a little dis- very large, equaling or perhaps even 

 tance to distinguish some of these surpassing in size some of those within 

 fossil trunks from the lichcn-covcred the limits of the park, 

 stumps of kindred living species. Such In the beds of the streams and gulches 

 an aggregation of fossil trimks is there- coming down into the Lamar River 

 fore well entitled to be called a true from Specimen Ridge and the fossil for- 

 fossil forest. It should not be supposed, ests one may observe nimierous pieces 

 however, that these trees still retain of fossil wood, which may be traced for 

 their limbs and smaller branches, for a long distance down the Lamar and 

 the mass of volcanic material falling Yellowstone Rivers. The farther these 

 on them stripped them down to bare, pieces of wood have been transported 

 upright trunks. downstream, the more they have been 

 These fossil forests cover an cxten- worn and rounded, imtil ultimately 

 sive area in the northern portion of the they become smooth, rounded "pebbles" 

 park, being especially abundant along of the stream bed. The pieces of wood 

 the west side of Lamar River for about become more numerous and fresher in 

 20 miles above its junction with the appearance upstream toward the bluffs, 

 Yellowstone. Here the land rises rather until at the foot of the cliffs in some 

 abruptly to a height of approximately places there are hundreds, perhaps 

 2,000 feet above the valley floor. It is thousands of tons that have but recently 

 known locally as Specimen Ridge, and fallen from the walls above. One trav- 

 forms an approach to Amethyst Moun- ersing the valley of the Lamar River 

 tain. Thtre is also a small fossil forest may see at many places numerous up- 

 containing a ntimber of standing trunks right fossil trunks in the faces of nearly 

 near Tower Falls, and near the eastern vertical walls. These trunks are not 

 border of the park along Lamar River all at a particular level but occur at 

 in the vicinity of Cache, Calfee, and irregular heights; in fact, a section cut 

 Miller Creeks, there are many more or down through these 2,000 feet of beds 

 less isolated trunks and stumps of fossil would disclose a succession of fossil 



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