Another Olive Tree Update!

A few months ago we reported on the status of some olive trees in our grove that were failing to thrive after their being transplanted to the UC Davis Good Life Garden in September of 2008. Their issues were the result of a percolation problem. What is that you ask? Well, essentially it means that water cannot penetrate or "percolate" into the ground where plants or, in this case, trees are growing; the cause of this issue came as a result of all the soil compaction that occurred during the construction of the surrounding buildings at the Robert Mondavi Institute for Wine and Food Science. To read more about this issue click here.

A few days ago we replaced three of the original trees, but have included a much better drainage system; incorporating a layer of crushed rock over drainage tubes covered with amended soil will hopefully provide a more comfortable growing environment for these historic campus trees. (See a photo of the start of this process below.) Our Grounds and Landscape Services crew will continue to monitor the situation and support the trees health in their new homes.



According to UC Davis Director of Grounds and Landscape Services, Sal Genito, who I spoke with about the project this morning, "The key to good plant growth is great drainage." He also mentioned the tell-tale sign of a plant struggling with percolation issues, "The soil smells rotten, like eggs, due to a build up of bacteria that can't escape."


Photo above: A flat bed trailer transports the trees to their new location from a historic campus owned grove in Woodland, California.

Photo below: A crane lifts one of the olive trees off the flat bed trailer and into its new location complete with necessary drainage.

Seasonal Fruit Profile: Olives

Growing tip: Olive trees are hardy, drought-tolerant and can bear fruit for a thousand years.

Did you know? The olive is a unique fruit—it is inedible unless cured, and is the only fruit from which a food oil can be extracted. (Other food oils are extracted from nuts or dry grains). The pulp layer surrounding the large central seed can be up to 30% oil.

In history: Olives were first planted in California at the San Diego Mission in the late 1700s, with the first olive oil reported to be produced in California in 1803.

About the fruit: Olives are native to the area that today includes Syria, Iran and Palestine; cultivation then spread to the Mediterranean basin 6,000 years ago.

Health: Olives are high in monounsaturated fat, which studies have correlated with cardiovascular health.

In the garden: Our olive trees are trellised to demonstrate the ‘super-high density’ olive farming method gaining popularity in California. Trees trained in this manner can be planted closer together than traditional olive orchards and can be harvested mechanically.

Learn more about olives by visiting our website.

Sources:
McGee, Harold. On Food and Cooking: The Science and Lore of the Kitchen. Scribner: New York, 2004.
Health content provided by Liz Applegate, Director of Sports Nutrition, UC Davis, www.lizapplegate.com.

Olive tree update

If you have been by the garden lately, you may have noticed that some of the olive trees in the grove aren't looking very healthy. The poor health of the trees is not due to neglect, but is due instead to a percolation problem that presented itself after the trees were transplanted last October.

What is a percolation problem? It simply means that the water cannot percolate, or absorb, into the soil. This is due in part to the the recent construction of the courtyard which contains the same compacted soil necessary to create a stable foundation for the surrounding buildings. The soil was compacted and then hardened, and now water simply sits there without draining, creating the perfect environment for a bacterial infection of the root system. Nevertheless, despite the fact that two of the trees appear to be dead, they still have live growth on them, and our Grounds crew is working hard to come up with a solution. Below is a photo of one of the trees being transplanted last October.