The world's largest plow(s)

The Post Brothers plow, as it appeared in 2012. 

From housing tracts to Little Saigon's strip malls, today it's hard to tell that Westminster was once mainly a farming community. That's why it comes as such a surprise to stumble across the world's largest plow at the southwest corner of Brookhurst Ave. and Bishop Place. Even more surprising is that the plow is part of a controversy.

The Post Brothers' plow was built by Charles R. "Hap" Post and Norman R. Post in 1937 to reclaim farmland ruined by large quantities of silt deposited by the flooding Santa Ana River. It came in handy again in 1938, when the flooding was even worse.  At a rental rate of $100 per hour or per acre, the enormous carbon steel blade pulled Westminster's famously rich topsoil back to the surface.

The Post Brothers' plow, being pulled by a long row of tractors.

The plow is 15 tons, 37 feet long, 12 feet high, 11 feet wide, and has a 86-inch blade. Each wheel is more than six feet across. In the photo above, the plow is being pulled -- as was the norm -- by a series of five "100 Drawbar h.p. D-8 Caterpillar tractors."

Standing in the furrow cut by the Post Brothers' plow.

In addition to restoring thousands of acres of farmland throughout the Santa Ana Valley, the plow was also used to cut ditches for drainage and pipelines. In the 1940s it served the war effort in Nevada, digging trenches for cables at bomb test sites. (Next time there's a power outage in Westminster, you might want to stop by and see if the plow glows a little.)

According to local historian (and former Westminster mayor) Joy Neugebauer, Tom and Miriam Warne acquired the plow from Hap Post and put it on display at their "Rancho Bolsa" as a way to share the area's agricultural heritage with future generations.

Another view of the Post Brothers' plow from 2012. (Photo by author)

You wouldn't think a giant plow could be controversial. But this one is. Thanks to Fountain Valley historian Dann Gibb, we now know there's a twist to this story. 

Around 1931 – six years before the Post Brothers’ plow -- Greenville (South Santa Ana) farmer Paul Plavan dreamed up and designed a giant plow of his own. His intent was the same: Bringing to the surface the rich peat soil that lay hidden beneath the sandy topsoil of Talbert (now Fountain Valley) and Greenville.  His design featured a six-foot-long blade that cut a 42-inches deep furrow. He built most of the plow himself in his own blacksmith shop on this ranch in Greenville, with some help from Talbert blacksmith Roy E. Wise.  It took three tractors to pull it, and in January 1932 the Los Angeles Times proclaimed it the world's largest plow.

Paul Plavan with his plow in the Jan. 21, 1932 edition of the Los Angeles Times.

The Plavans later said that they rented their plow to the Post Brothers, only to discover that the Posts had disassembled and reverse-engineering it in order to build their own verions, only almost twice as big. The Post boys also had the foresight to patent the design. (Something Plavan failed to do.) 

Is building larger plow really a steal-able innovation? Was one plow a direct knock-off of the other? Was this just a typical case of plow size envy? Or was there an actual theft of unique design elements? Since we no longer have the Plavan plow or its plans, it’s hard to say with complete certainty. But we do know the whole incident generated bad blood down in the peatlands.

Update 8/30/2023: The Post Brothers Plow was recently moved to the front of the Westminster Historical Society's museum grounds at 8612 Westminster Blvd. It can be clearly viewed from the street.