Portuguese neighborhoods in San Jose and other big cities might be identifiable by the presence of the otherwise rare cork oak, Quercus suber. After all, they are native to Portugal, as well as Spain, Sardinia, Corsica, Sicily and the coast of the Mediterranean Sea as far east as the eastern tip of Italy on the north, and the northwest corner of Libya on the south.

Like redwoods, cork oak is one of the few species of trees that survive forest fires by being less combustible. Their foliage and small twiggy stems may burn, but larger limbs and trunks are insulated by very thick cork cambium (bark). Most other trees that are adapted to burning either disperse their seeds as they burn in order to get a head start at reforestation afterward, or simply resprout from their roots.

 Ironically, this bark that is intended to help the trees survive was actually the reason why trees on the north coast of Algeria were so extensively and detrimentally harvested during French  colonialization. Corks made from the bark were needed for the wind industry in France. Fortunately, cork in Algeria is now harvested like it is in other regions, without harming the trees that produce it.

Compared to other oaks, cork oak is not too large. It can get a bit more than fifty feet tall and nearly as wide, but takes a century or more to do so. It can actually stay proportionate to urban landscapes for a very long time. Roots are mostly complaisant. The main problem with cork oak is that it drops its evergreen foliage constantly, and drops floral debris and acorns for a few months.

Gnarly trunks and limbs with spongy bark are the main appeal. The one and a half or two inch long leaves are not so interesting. They are barely convex, often with a few blunt lobes, and dull grayish green from below.