BULLETIN 231] WALNUT CULTURE IN CALIFORNIA. 131 



western slope of the Sierra Nevada, the San Joaquin Valley, and 

 on both sides of the Sacramento Valley. In each and every case the 

 history and original planting of these old trees, which represent the 

 largest California black walnut trees in the State, can be definitely 

 ascertained. In his investigations on the subject Jepson found two 

 localities where this tree appeared to have been growing naturally at 

 the time of the advent of the first white settlers. On this point he 

 states as follows:* "There are two centers of distribution, one in the 

 north and one in the south, without connecting localities so far as I 

 have been able to determine. In the north it occurs in the lower Sac- 

 ramento region, keeping to the banks of the river islands of Andrus, 

 Grand, and others, and along streams in the valleys at the western base 

 of Monte Diablo, specifically on Walnut Creek and Lafayette Creek." 

 In our investigations conclusions were reached coinciding with Jep- 

 son 's, that these were two of the original homes of the northern Cali- 

 fornia black walnut, and a third location was added to the list which 

 appeared to be older than either of the other two. This was a station 

 known locally as Walnut Grove, situated on the east slope close to the 

 top of the first divide east of Napa, near Atlas post office. In this 

 locality there exists along the mountain-side, near the top, a series of 

 small ponds or marshes, each consisting of a cup-like depression or ter- 

 race in the hillside, about the edges of which discharge several springs. 

 Each of these terraces no doubt contained at one time a small body of 

 water, but in the course of time they have filled up with vegetation 

 and soil into swamps and mud holes. There are some eight or ten of 

 these formations scattered along the hillside within a mile or so, the 

 largest, the northernmost one, having an area of possibly three or four 

 acres. The whole hillside throughout this locality is covered with a 

 dense growth of native trees characteristic of the region, particularly 

 the Oregon maple and black oak, with California laurels and madrones 

 in the deeper canons. The soil is deep and moist upon this slope, and 

 all vegetation is very luxuriant. On the largest and northernmost of 

 the little basins mentioned there stand, near the north end, three large, 

 black walnut trees, one of which appears to be by far the oldest wal- 

 nut tree in the State. This consists really of a group of seven good 

 sized trees, all arising from a common base, which evidently are sprouts 

 or second-growth from the stump of a still older tree. The individual 

 stems in this group form very tall, clean trunks, as upright and tree- 

 like in form as the best type of the eastern walnut. The other two 

 trees in this group have single trunks at the base, growing up with 

 clean, erect trunks and lofty, spreading tops. They resemble the first 

 mentioned tree in most respects, save that one of them has deeply fur- 



*Bulletin of the Southern California Academy of Science, Vol. 1, p. 23, 1908. 



