Melaleucas are blooming now; there’s a double row of Melaleuca linariifolia on Jefferson Street, on both sides of its intersection with Bancroft, and a nice row of them by the BART tracks on Masonic in Albany, among others. They look nifty in rows, with their profusion of tiny white flowers mounding the edges of the rounded crowns. One of their English names is “snow-in-summer,” a name shared with an easy herbaceous groundcover, Cerastium tomentosum. They look a little odd together, though, because they have such different color palettes: The tree is pale tan and slightly olive-ish green with creamy flowers, and the herb is silvery and cold white.
The other English name of the melaleucas on Jefferson street is “flaxleaf paperbark.” The leaves are small, thin, and stiff—almost prickly—and the bark is pale and very odd indeed. If you find one of these trees, touch it—poke it, in fact. The bark is thin and papery and exfoliates in bits and layers, but there’s so much depth to it that it feels densely foam-rubbery, much bouncier than cork. You press it and half expect the tree to object: “Oof!” It’s half the fun of knowing the tree.
That bark, though it looks like so much tinder, functions to protect the tree against fire, rather the way redwood bark does. Melaleucas are members of an Australian genus, mostly, and like eucalypts they have learned how to survive wildfires—in fact, fire is one of the conditions that select for melaleucas as opposed to other species. They tend to like wetter conditions that most eucs, though, so they compete better in marshy spots back home. They’re members of a taxon that stayed with Australia when the Gondwanaland supercontinent broke up, along with eucs and banksias and those other odd things like casaurinas. (It amazes me sometimes, how many of the Gondwana species thrive here—makes the place seem like a sort of biological antique shop.)
From what I’ve seen, the melaleucas planted most often here are that flaxleaf paperbark and its cousin Melaleuca quinquenervia, cajeput tree. I haven’t heard of their being invasive in California—and they stand little chance of invading our wildlands from the sites I’ve seen them in, surrounded by pavement—but cajeput is certainly a pest back East, especially in Florida. In several states there, it’s an official weed. It’s threatening the Everglades, substituting a practical monoculture of its biologically useless seed-lings for the sawgrass that is the foundation of that incredible, unique environment.
Another cousin, Melaleuca alternifolia, is the source of that medicinal fad, tea tree oil. It occurs naturally in only a small area of New South Wales, but people have been making plantations of it all over. The yield of oil is scant—one or two percent of the weight of leaves and branches that get distilled—so if the stuff tests out well enough to get really popular, it’s going to take a lot of trees and land. I have found it to be pretty allergenic and straightforwardly irritating when aerosolized (as in a topical spray) myself, so be warned. It certainly smells… effective.
In California flaxleaf paperbark is popular as a street tree, for good reason. It’s droughty but tolerates water and poor drainage, which we get with our clay soils and aggravate with city conditions like paving and compacting soils. It’s easy on sidewalks, doesn’t buckle them much. It’s short, so it works well under powerlines. And it’s pretty! It seems worth the bit of labor it requires, sweeping up its spent flowers in summer.
There are 170 to 200 species of melaleucas (the number is disputed, as species are still being described) and some are pretty handsome. Many have flowers that resemble those of bottlebrush—no surprise, as they’re close relatives. It would be interesting to see what others would make it as street trees, though the example of invasive cajeput would suggest caution. Meanwhile, go have a look at the flaxleaf paperbarks in and around Berkeley. They’re handsome as single specimen trees, but the effect of a row of them lining a street is grand. And go ahead; give one a squeeze.