SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 23 
/ The Distribution of Juglans Californica Wats 
By Willis Linn Jepson. 
The range of Juglans Californica, the solitary native walnut 
of the Pacific Coast and commonly known as California Wal- 
nut, is from the lower Sacramento to Southern California ac- 
cording to the more recent books of Californian botany. This 
statement of range does not well express the true state of the 
case. 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 Sacramento 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 the south it ranges 
from the Ojai Valley southward and eastward along the south- 
ern base of the Sierra Madres and San Bernardino range as 
far East at least as San Bernardino. Mr. Parish tells me its 
altitudinal range there is 1800 to 4500 feet. Southward it oc- 
curs in the Puente Hills according to one of my forestry stu- 
dents, Mr. C. N. Forbes, and in Breada Cafion of the Santa 
Anas on the road from Fullerton to Chino, according to Mr. 
C. H. MeCharles, this the southermost locality known to me. 
“Santa Barbara, Torrey’’ is a classical loeality needing con- 
firmation. 
There are fine trees on adobe soil near Covina, associated 
with Sycamore and Live Oak. Thirteen trees in this locality 
selected by Miss Rea Elliott measured 4 1-6 feet to 8 2-3 feet 
in circumference near the ground. One may see this species to 
advantage in the Hollenbeck Pass on the way from Covina to 
Spadra. Near Azusa the trees are frequently eut down, but 
stump sprout freely according to Miss Harriet Smith. The 
same observer notes that the small trees (10 to 15 feet high) in 
sandy soil in the Sierra Madre foothills bear galls whilst trees 
in adobe soil do not seem to be so affected. 
