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AMERICAN FORESTRY 



of bark were saved ; masses of leaves 

 and twigs matted in the asphalt were 

 examined with microscopic eyes to see 

 if they were mere drift, or the stomach 

 contents of herbivorous animals. Bush- 

 els of loose material were washed in 

 gasoline through sieves for seeds, in- 

 sects and the thousand and one minute 

 forms otherwise lost. This work is 

 usually delegated to one man, w 7 ho for 

 the time being does nothing else, for it 

 is found that after working on a skull 

 (the mastodon, for instance), that takes 

 four men to lift, one was apt to over- 

 look a specimen as small as the scapula, 

 for instance, of a shrew, the size of a 

 pin head, especially if hidden in a clod 

 of la brea the size of one's fist. 



"At fifteen feet a network of large 

 roots was encountered intermingled 

 with skulls and bones of bison, camel, 

 tiger, wolf and sloth. Working around 

 to the north, the roots were found firm- 

 ly imbedded in a bank of oil-soaked 

 clay, proving that the tree had grown 

 where found. All sorts of conjectures 

 have been made, some wise and some 

 otherwise. Out of it all we may con- 

 clude that the tree once grew on the 

 bank of a small run or depression, the 

 roots on one side firmly imbedded in 

 the bank. On the other side they ex- 

 tended into a soft, perhaps muddy basin. 

 The ever shifting gas, under heavy 

 pressure, in its effort to reach the sur- 

 face, probably followed the root of the 

 tree as the point of least resistance. 

 Once at the surface the asphalt deposit 

 commenced and the trap began its work, 

 slowly, over hundreds of years of time, 

 until the tree was completely covered as 

 the surrounding country gradually 

 filled. 



"One wonders why the tree did not 



decay and fall before these long years 

 elapsed. We know that all its smaller 

 branches and limbs did decay, as the 

 worm-drilled ends attest, leaving only 

 the ponderous trunk, 18 inches in diam- 

 eter, and one main fork. There seems 

 to be only one probable solution of the 

 question. Certainly the tree must have 

 been killed soon after the oil penetrated 

 its root area, and it seems almost as 

 certain that as the sap left the tree it 

 was replaced by the penetrating asphalt- 

 laden oil, the wonderful preservative of 

 Rancho La Brea. That it did its work 

 well is certain for the wood is sound 

 enough to make into furniture today. 

 An authenticated sample of the tree 

 was sent to the Biological Survey at 

 Washington for analysis, and micro- 

 scopic slides were made of transverse 

 and cross sections, showing that the 

 tree was a cypress {Cupressus inacnabi- 

 ana). Many fragments of wood have 

 been thrown out of the pits and visitors 

 have carried pieces away. In some in- 

 stances these have been sent out as 

 fragments from the tree, with the result 

 that the tree has already had three 

 scientific names attached to it. The 

 name Cupressus macnabiana, however, 

 must stand for the present, as it is based 

 on a true sample of the tree." 



(The specimen of wood from the 

 tree was sent to H. W. Henshaw, chief 

 of the Biological Survey at Washing- 

 ton, D. C., to determine its identity. 

 Dr. Albert Mann, of the Bureau of 

 Plant Industry, made a few slides, and 

 the tree was determined by Mr. C. D. 

 Mell, of the Forest Service, to be a cy- 

 press, technically, Cupressus Macnabi- 

 ana, Murr., a species which is still pres- 

 ent in California. EDITOR.) 



Pennsylvania's TMO Arbor Days. 



The State of Pennsylvania celebrates two arbor days each year one for spring planting 

 and one for the fall in April and October, respectively. 



