As the devastating Santa Anas roared through Southern California last week, everyone was talking about the wind but nobody could do anything to stop it.  But once, well over a century ago, a Los Angeles editor revealed a plan to block those already dreaded Santa Ana winds from decimating the region. What went wrong?

The idea generated by Isaac Kinley, editor of SoCal’s first daily, The Star, appeared in an editorial in 1879. It may be the earliest reference to the Santa Anas in print. Although Kinley didn’t call them by that name, referring instead to “the Cajon invasion,” everyone knew what he meant. 

By 1879 the Santa Anas were already considered a threat to the infant citrus industry. Kinley’s idea originated in part out of the concerns of orchardists whose trees and crops were at the mercy of those winds. Without citing any figures, he argued that the monetary loss through damage by the Santa Anas would more than pay the cost of blocking the wind. 

Kinley’s solution? Erect a wall across the Cajon Pass, blocking the wind and protecting residents and orchards in the flat land below.

In essence, Kinley’s  brainchild preceded one proposed a few years ago by a Temple University physicist who would break up Mississippi Valley tornadoes by building an east-west wall a thousand feet high along the Oklahoma-Kansas border. This would so disrupt the merger of air masses that cause tornadoes that any destruction of cities and farms would be greatly reduced. 

Kinley’s wall would only have been 300 feet high, stretching across the pass. Instead of a barrier of brick and mortar, Kinley would rely on a thick forest of eucalyptus trees, with a row of Monterey Cypress on the north edge. 

Eucalyptus had already appeared in California, although the tallest trees were far short of the 300 feet Kinley believed was necessary to effectively block the wind. From his window, as he wrote the piece, he could see a young tree about eight years old that already stood a hundred feet high. The tallest eucalyptus tree  in Australia, the “Centurion,” was last measured at 327 feet tall, but there are reports of a fallen eucalyptus in Tasmania that measured over 400 feet. Kinley’s proposal was not unrealistic in that respect. A hundred year old grove of blue gum eucalyptus on the Berkeley campus of the state university has the tallest eucalyptus in California at 225 feet.

But Kinley would not confine his efforts to the pass alone. He urged citrus growers to line their orchards with rows of eucalyptus as potential wind breaks, whether or not the main breastwork was planted in Cajon Pass. 

In Kinley’s day the Santa Anas came far less frequently than now. He implied that the destructive winds that had just blown through SoCal came  perhaps once in a score of years, but even that was once too often considering the damage they did. They now come several times a year, and the major threat is not to the citrus crop. It is through the wildfires that are either started or fanned by the Santa Anas.

Kinley’s eucalyptus windbreak at Cajon Pass would not have protected Ventura and Santa Barbara counties, where the catastrophic Thomas Fire two years ago was fed by Santa Anas that came over another mountain range, which is much lower than the San Gabriel and San Bernardino mountains. Nor would his wall have had any effect on the recent fires in Santa Clarita or Simi Valley, where the winds came down the Tejon Pass or over the 14 freeway from Palmdale.

The  Cajon Pass wall was never planted, but ranchers and orchardists followed Kinley’s advice and lined their properties and groves with eucalyptus. While most of those windbreaks disappeared as groves gave way to subdivisions, many trees remain today, outlining what once was a citrus grove or farm. 

The tornado walls will probably not be built, for the idea received almost universal condemnation from fellow scientists. A plan to build a tsunami wall to protect Japan from tidal waves probably won’t be built either. But “hurricane shutters” have already been proposed, with the hint that they may also work against Santa Anas. And the Chinese planted a “green wall” along the Mongolian border in the 1970s to reduce the flow of dust into central China from the desert. It’s unlikely they got the idea from Kinley.

Kinley’s eucalyptus breastwork probably would not have stopped last week’s Santa Anas. UC Berkeley professor  emeritus of environmental planning Joe McBride, a specialist in urban forestry, believes that the Santa Anas would simply rise over the eucalyptus barrier and descend upon SoCal unhindered. Both major passes into this area are slightly over 4000 feet in elevation, and the wind already crosses the mountains at higher points.

Furthermore, as McBride has noted, eucalyptus trees are susceptible to frost, and their growth at an elevation of 4000 feet would be problematic. More than that, eucalyptus, particularly in the Oakland/Berkeley hills, have been a major concern because of their potential for burning and, because of their height, the danger they pose to adjacent power lines. It was a eucalyptus tree that shares the responsibility for last week’s Getty fire.

While his “green wall” in Cajon Pass was perhaps a pipe dream,  Kinley tried to do more than just talk about the Santa Anas.


Ralph E. Shaffer is professor emeritus of history at Cal Poly Pomona.