I found an interesting person working in the Huntington Library/Gardens in Pasadena, CA. He is Terry Eagan. And he was making cement in the garden.
What he was doing was repairing a long cement pergola made in the shape of trees. It is the longest sculpture in the garden and was originally created in the teens and 20's. The art is called fax bois, and was started in France. I remember that Butchart Gardens has a number of faux bois railings. These pergolas are quite extensive throughout the rose and Japanese gardens. He says he'll be repairing for a few years to come yet. And he started a few years ago. It was interesting to see that he had to cool the cement mixture, as it was so hot in Pasadena at the time - 106 degrees.
Here's the link to his site: http://www.fauxboisconcrete.info