Saturday, July 17, 2010

Why Eucalyptus Trees Cover the East Bay Hills

Photo of eucalyptus leaves by nothing on Flickr

During the long summer days, the hills to the east of San Francisco Bay (Alameda and Contra Costa County) are wonderful places to walk — not too hot and with remarkable views to the east, west, and north (until the fog rolls in, and then it's grey in every direction). The land in the East Bay Hills was originally open grassland with occasional small stands of trees like live oak, madrone, and willow. Most of the year it was "golden", but after the winter rains the grasslands exploded with the colors of wildflowers among the green grass. Today, however, the hills are covered with eucalyptus trees imported from Australia. So how such a concentration one type of tree come to the hills Berkeley and Oakland? The July-September 2005 issue of Bay Nature had a fascinating story by Bill O'Brien about how it happened. It is a tale of optimism, hard work, greed, and how nature can wreck humanity's plans.

But first, why should anyone care? While many imported plants behave nicely and stay in the region they are planted, others rapidly expand their range and out compete the natives. The Nature Conservancy's Invasive Species Initiative says this about non-natives:
On their home turf, plant and animal populations are kept in check by natural controls, like predators and food supply. However, when a species is introduced—accidentally or intentionally—into a new landscape that is not used to its presence, the consequences can be devastating. Most of these “non-native” species do not misbehave. But some non-native species spread unchecked by the lack of natural competitors and predators. They push out native species and cause ecological chaos.
Eucalyptus trees are ecologically problematic and notoriously flammable (they tend to explode when they burn and flaming pieces of bark can be carried long distances by the wind). Stands of eucalyptus tend to be less diverse than native lands, but by no means devoid of natural life. O'Brien writes that " A recent study by biologist David Suddjian counted more than 90 bird species that make regular use of Monterey County eucalyptus habitats, including at least 59 species that nest in them. Eucalyptus trees on the shores of San Leandro's Lake Chabot host a large heron rookery. In Santa Cruz County, Suddjian found that great egrets, great blue herons, and double-crested cormorants nest exclusively in eucalyptus." And at Ardenwood Historic Farm in the southern East Bay, monarch butterflies use eucalyptus for shelter and sustenance as they over-winter in the Bay Area. The trees are remarkably resilient, so removal of the forests is not easy: chop one down, and the next season the stump be covered with vigorous new shoots.

Haven's Dream
Almost all of the eucalyptus in the East Bay Regional Park District can be traced to a company founded by Frank Havens (1848-1918). Havens was one of the early builders of Oakland and Berkeley, most notably public transportation and utilities. He was also a partner in the company that built the Claremont Hotel. At various times he worked with Francis "Borax" Smith, who originated the Twenty-mule-team borax product.

Havens founded the People's Water Company in 1906, with holdings that stretched from Richmond to San Leandro. In 1910, his Mahogany Eucalyptus and Land Company started planting seedlings. Since California had little native hardwood and the population was rapidly growing, Havens' goal was to create a local source of lumber (and revenue, of course). Eucalyptus was thought to be ideal because it was fast growing and the trees coppice readily (i.e., sprout shoots from a cut stump), thus reducing the need for replanting. Somewhere between one and three million seedlings were planted in the East Bay hills between 1910 and 1914. Havens' firm also built 9 plant nurseries, a sawmill, and arboretum. During the peak planting season the company employed as many as 200 people.

Havens' dream died quickly — he shut it down in 1914, just four years after starting the project. Although the trees grew rapidly, they were unsuitable for lumber because they were difficult to plane without chipping and the wood cracked while drying. The article does not give a definitive reason for the failure of the project, but some have theorized that the mild Bay Area climate and lack of natural pests caused the trees to grow too quickly, which led to wood characteristics that were different than those found in Australian trees.

Like many other get rich schemes in California (hydraulic mining, for example), a short burst of activity had long-lasting impacts on the ecosystem, ones that we are still dealing with many decades later.

Additional Resources

Photo of eucalyptus from Nothing's flickr collection, subject to a Creative Commons License.

Random link from the archive: Kingfisher World Curry Week - Eggplant Curry


Sunday, July 11, 2010

Pizza Pie Charts: Looking at Pizza Service

Although pizza baking in the San Francisco Bay Area and other locations (e.g., Sunset's list) has undergone a renaissance in recent years with higher-quality ingredients, improved techniques, and better ovens, I think that the service side of the pizza scene needs some serious work. I'm not talking about the people who take your order or bring your food, but the way that carefully-made delicacy is delivered to the table.

Recently, I went to one of San Francisco's top pizza places and the pizza was served on a thin aluminum pan. And so, in the minutes between service and consumption, the crust gets soggy and the quality rapidly drops. One way of looking at this degradation is through charts -- a type of pie chart, I suppose -- which give a graphical interpretation of how my impression of the pizza's quality changes over time.

Pizza Pie Charts
To explain my pizza eating experience, I made three charts, using a photo from atduskgreg on Flickr as a background. On each photo of the pizza (from Delfina Pizzeria in San Francisco), there are four black and white bars.  The black part of the bars indicates the quality of that section of the pizza at that moment in time, with a solid black bar being perfection for that particular pie.  There are four bars on each pizza that correspond to the center, inner third, outer third, and edge of the slice.

The first figure shows my opinion of the pizza's quality at the moment of delivery (your sense of pizza quality might be totally different, of course). The black bars are as high as they will ever be because the crust is crispy across the entire slice.

Pizza graph using photo from atduskgreg on Flickr

A few minutes later, degradation occurs in the middle of the pizza, as moisture released by the hot crust and toppings lead to the first stages of sogginess in the crust. As you go to the outside edge, however, the quality remains fairly high because there are escape paths for the moisture.

Pizza graph using photo from atduskgreg on Flickr

As time goes on, the trend continues, with the center of the pizza degrading faster than the outside.

Pizza graph using photo from atduskgreg on Flickr

Another way to look at the pizza trends is with an x-y chart. In the chart below, the y-axis is quality of the pizza at a particular location and the x-axis is time (in arbitrary units because I haven't timed my pizza. Each unit is probably a minute or so.). As noted above, the quality of the pizza drops more rapidly in the center than at the edge.

Chart of pizza quality

Maintaining Quality
So how can pizza quality be maintained at very high levels for more than a few minutes?

Many slice shops have developed a system that gives the diner high quality: upon receiving an order they take a slice from the display case and pop it into a hot pizza oven for a few minutes to crisp the crust and heat the toppings. But this approach is necessitated by a feature of the slice business: they need to have a lot of 'inventory' ready to sell at a moments notice, as not many slice customers want to wait for 10 or 15 minutes for their order. At a place like Delfina, Pizziaolo, or Flour+Water, in contrast, the pizza is made to order and delivered directly from the oven to the table.

pizza a taglio photo from Daniele Muscetta on Flickr
Photo from Daniele Muscetta, subject to a Creative Commons License

One idea that comes to my mind is cooperative ordering: diners at different tables would stage their orders and share partial pizzas. Here's how it would work in theory: imagine that two couples at different tables are each going to order a pizza. Instead of getting one pie each at the same time, they could arrange for the server to bring the two pizzas to the two pairs in stages: half of the first pizza goes to each table, then each table gets half of the second pizza a little while later. This pizza sharing approach shrinks the time between pizza delivery and pizza consumption, thus hopefully increasing the enjoyment. How a restaurant would deal with this is another matter, as it isn't trivial to coordinate orders from multiple tables.

Other ideas address how the pizza is delivered. Instead of putting the pie on a basic, non-permeable pan, could a wire rack prevent sogginess?  Or would it cause the pizza to cool down too fast?  Or could a combination of hot bricks and a wire rack like the one pictured below be a solution?  In theory, the heat from the bricks would keep the bottom of the pizza warm while the wire rack allows moisture to escape.  Or would it be a too dangerous?

Or perhaps this is all much ado about nothing... In any case, do your favorite pizza places have any non-standard ways of serving pizza?

Photo Credits
The pizza charts were created using a background photo of pizza at Delfina Pizzeria in San Francisco from atduskgreg's flickr collection, subject to a Creative Commons License.  The bottom photo, pizza a taglio, is from Daniele Muscetta's flickr collection, subject to a Creative Commons License.

Random link from the archive: Kingfisher World Curry Week - Eggplant Curry