A post on the Facebook page “You Know You’re from Chico When . . .” alerted me to a news story on KRCR Channel 7 about the old rock walls you see along Humboldt and Cohasset Roads. Dennis Van Dyke and Debbie Meline are working to protect and preserve the walls and are asking people not to remove rocks from them. They have a Facebook page dedicated to the walls called “Respect the Walls.”
A lot of people are curious about those walls: Who built them? Why? What are they for?
I turned to the Butte County Historical Society’s quarterly journal Diggin’s to see if it had anything. According to the online index, there have been two articles about the walls, one in the Winter 1858 issue, and one in the Winter 1974 issue. I don’t have the 1958 issue on hand, but here is the text of the brief article that appeared in 1974. It seems to have originally appeared in the Chico Enterprise-Record on July 21, 1971.
ROCK WALLS
Manuel Picanco, aged Chico resident, was one of the three Portuguese craftsmen who handled the construction of the endless miles of rock walls one the Cohasset, Humboldt, and Neal Roads nearly 60 years ago. That is the story told by Charles McClard, 134 W. Third Ave., who at one time worked on construction of the walls. They were erected by owners of two great cattle and hog ranches east of town to keep stock within the bounds of the property.
McClard said that ranch hands, during their idle months between harvest, pried the large rocks out of the ground and called them to the wall site. However, McClard said, three Portuguese craftsmen, one of whom was Picanco, handled the actual placing of the rocks. The walls were constructed with such exactness, that after over half a century no major rebuilding of the unique walls has been necessary. Constructed over a span of six years, the walls are four feet thick at the base and two and one-half across the top.
If the walls were constructed 60 years before this article appeared in 1971, then they were built in the early years of the 20th century, and are now over 100 years old. We should indeed protect them and respect them.
goldfields 
Thanks for researching this. The Chinese are quite often given credit for construction of the rock walls. Nice to know this is not true.
Thank you for this post Nancy. We are working hard to get the city and public onboard to support this cause. The news story caught the group a little by surprise but I have started working on a website to act as a reference point for those that are interested. I will be adding more content from past meetings, as well as diary entries and stories that were written long ago and lost in time until now. Please feel free to contact me if you would like any more information and be sure to look into the interactive map I have built showing nearly all the walls in the greater Chico area.