Caveman (Araucaria bidwillii)

Two species of Araucaria are used as houseplants: A. heterophylla, also known as the Norfolk Island Pine, and A. bidwillii, which is also known as . . . well, it's not really known as anything, because they're pretty uncommon indoors. Though outdoors, they're called "Bunya-bunya" trees. Sometimes. Mostly in Australia.


We'll get to some reasons why they're uncommon,¹ but first, let me try to impress upon you exactly how old this genus is. Fossils of Araucaria, often in the form of petrified seed cones and wood,² are known from the Jurassic period (135-180 million years ago). I had difficulty finding any solid numbers on ages, but fossil Araucarias from 220 million years ago are apparently not unheard of. These, it should be noted, are not the modern-day A. bidwillii, just a tree from the same genus.³ Even so, this is a long time for a genus to survive, and bidwillii is a close enough relation to the fossils that even a non-expert can see a resemblance (see the link here).

Petrified log at Petrified Forest National Monument. Photo by Jon Sullivan, listed at PDPhoto.org and found through Wikipedia. This is probably not a petrified A. mirabilis: mirabilis is apparently mostly found in South America.
Most of us have no real concept of how long ago 220 million years ago was, and I can't think of any good way to explain it, because I'm one of most of us. Maybe it's just me, but I've always been left somewhat cold by analogies like, 220 million inches is . . . whatever it is, or if every year were shrunk down so it took only a second -- it's better than nothing, kinda, but I have no intuitive feel for those kinds of numbers; I don't have everyday experience with circling the equator sixty times or 180,000 years or whatever either. So what to do? Let's try something else:

Araucaria spp. are so old, when the species first differentiated, the Dead Sea was only beginning to get sick.

No? Lemme try again:

Araucaria spp. are so old, John McCain climbed them as a child.

Over the line? Okay, one last try:

Araucaria spp. are so old, the first ones had to grow in the dark for three years before God finally said, "Let there be light."⁴

But more seriously: the Araucaria genus is so old, dinosaurs could have eaten them (and presumably did. I mean, something must have). They survived an asteroid striking the earth, mass extinctions, continents sliding around the earth like butter on a hot skillet, and multiple ice ages. This is an old group of plants.

So have some respect, I guess is all I'm saying. Araucaria was here first.

Adult Araucaria bidwillii. Photo by Wikipedia user Bidgee, taken of a 100+ year old tree in Collins Park, Wagga Wagga, New South Wales, Australia.

The tree is presently native to parts of Queensland, Australia, where it lives in rainforests. It has also been widely introduced outside of its native range, though, and cultivated specimens can be found on the U.S. west coast, the U.K., New Zealand, and parts of China. Specimens can get to be several hundred years old (600 is a pretty safe guess, according to one source) and a good 50 meters (164 feet) tall. It also has nice, straight stems, which produce nice, straight lumber, though logging mostly ended in the 1940s when the Australian government realized that if the remaining bunya-bunya habitat wasn't declared a national park or something, the species was going to be completely exterminated. Being sensible people, they made a park out of it.⁵

The bunya-bunya has mainly been of interest to humans for something else, though: its seed cones. Plants begin to bear cones at about 14 years of age. The seed cones resemble pineapples, though they're larger and rounder and can weigh as much as 4.5 kg (9.9 lb).⁶ Each seed cone (and there may be about thirty of them on a given tree) contains somewhere between 50 and 100 unusually large, edible seeds. There's a reason for the unusually-large part: we'll get there later. In any case, thirty cones to a tree, with maybe six pounds of seeds per cone, times however many trees are in the area, means lots of food available all at once, and whenever there's lots of food available at once, that means party. The catch is that this only happens every three years or so.

Seed cone of Araucaria bidwillii, partly torn apart. Photo by DRyan at the Wikipedia entry for Araucaria bidwillii.
In the years when the cones were being produced, the "custodians of the trees" would send around messengers to invite neighboring tribes to assemble near the trees. This would usually happen from January to March (Southern Hemisphere summer). The custodians would cut deep gashes in the sides of the trunk for traction (though occasionally this wasn't necessary because vines around the trunk could be climbed instead), and then they'd climb the trunks and knock the cones out of the tree canopy. The cones will fall on their own, too, of course, though this is not only inconvenient (only the tree knows when it's going to let go), it's seriously dangerous, too: a ten-pound cone falling 150 feet is going to have enough momentum behind it to kill a person.⁷

A lot of important business was conducted on these occasions: people hunted, arranged marriages, got into fights, held religious ceremonies, resolved conflicts, cheated on spouses, traded goods, shared ideas, made friends, and (I'm assuming) gossiped like crazy. (You know, the normal stuff that people do when they're in large groups that haven't seen one another for a long time.)

The nuts themselves can be eaten raw, roasted on coals, or ground into flour, and are supposed to taste like chestnuts. One site likens the texture to that of a waxy baked potato, which furrows my brow a bit. As partiers returned to their homes, they would bring nuts along with them (though it seems like they'd be pretty sick of them, after eating so many), burying a few here and there along the way.

Both the seeds and the early sprouts can be eaten, which brings us to the promised explanations for 1) why they're not common houseplants and 2) why the seeds have to be so big. You see, Araucaria bidwillii has a very roundabout way of germinating. First, the seed sends a root out, I guess to anchor itself and collect water, and then it grows a tuber, and eventually the tuber grows a first shoot, though this can take a long time, anywhere from two to twenty-four months. The first shoot is rosette-shaped, and has brown leaves; the plant grows green leaves and starts growing upright later. There's pretty wide variation in the length of time for any of these steps, which makes them frustrating plants to try to grow from seed, which is part of the reason why they're uncommon in cultivation: nobody wants to invest that kind of time for a plant that's that ugly. It's not like customers are breaking down doors to buy them.

My personal plant, from late October 2007.
Speculation abounds as to why the plant might have evolved such a roundabout way of germinating; protection against fire is one possibility. Another idea that's been floated is that maybe by building up a reserve of food in the tuber underground, the seeds are enabling a rapid push through and above neighboring plants, increasing their odds of survival, and by stretching out the germination period over a long time, they're hedging their bets as to when a good time to emerge might be. Neither of these satisfy me as an explanation: it seems to me like it took a lot of time and energy to build the seed in the first place, so why take that investment and make it burn even more time and energy rebuilding itself in the form of a tuber?

In any case, you'd need a large seed to be able to sustain itself over the two-year (potentially) germination process, hence the large seeds.

The tubers are edible as well, by the way, and are said to have a coconutty flavor. (Now I'm picturing a potato that tastes like a coconut, and finding it even harder to imagine than a nut that tastes like a waxy baked potato. Way to top yourself, A. bidwillii!)

My own personal plant has not done any head-bonking, and I haven't eaten it either, and it's been, altogether, a lot less dramatic than the above would indicate. In fact, I had trouble convincing it to do anything at all for several months after I got it.⁸ Then when we started opening the apartment windows in the spring, it kept getting blown off the shelf onto the floor: the soil it was in dried out incredibly fast, and was pretty lightweight to begin with, and so eventually we had to just stop opening that particular window. All the falling on the floor seemed to be good for the plant, though: it sprouted some new growth shortly afterward. Sometimes it helps to give them a good scare.

It still wasn't a fast grower, but at least there was something, and then it pretty much stopped again for a while. Since this spring, it's been growing pretty well, though, and has added another couple tiers of branches.

My personal plant as of 25 June 2008.

I'm not sure what to expect it to do next, whether it's going to continue its current rate of growth or whether it's going to stop again at some point and regroup. Either way, Araucaria bidwillii isn't a good plant for someone who wants to see a lot of fast, intense growth year-round.

I can't say we've had any major conflicts about care. When I bought my plant, I was pretty much flying blind: there's not much information out there about caring for it as a houseplant, and so I basically just treated it the same as an A. heterophylla, and that worked out just fine. This has been refined a little bit in the subsequent months, though:

Pests: Never had any issues with pests on this plant, either at home or at work.
Watering: The plant doesn't seem to be extremely inconvenienced by droughts, though I usually don't let mine go more than a week between waterings. I know it's possible to overwater them, because we've done that with some at work, but my personal plant is in such fast-draining soil that this isn't something I worry about at home.
Light: The ones at work sometimes go a bit yellow (even verging on orange), which I think is from getting too much light or heat or both. Bright indirect light with some direct sun appears to work fine at home.
Propagation: Supposedly Araucaria spp. will root and grow from a branch or tip cutting, but I've never tried it, and the results from branches are supposed to be very goofy looking. Seeds, if you're lucky enough to come by seeds and you don't eat them all, will yield better-looking plants, in theory, but will also take years, potentially, just to reach the pitiful stature of my plant pictured above.⁹

Araucaria bidwillii in 3-D, for those people who can cross their eyes properly. (The picture works like one of those Magic Eye pictures that were all the rage a while back: you have to sort of cross your eyes such that the two images overlap one another in the center of your vision, at which point, in theory, your brain should take over and interpret this as a 3-D image.)
Humidity: As far as I can tell, A. bidwillii is pretty much indifferent to humidity, though naturally, in the rainforest, they would be accustomed to it. Also their relatives (A. heterophylla, e.g.) like it, so it's something that could be helpful for an ailing plant.
Temperature: They're said to be hardy down to about 20ºF (-7ºC), though I haven't tested this myself. Excessive heat doesn't seem to be a huge problem either, though like I said, I suspect either too much heat or too much light of causing some bleaching and yellowing on the plants at work.
Grooming: Picking off dead branches as they occur, I suppose. I have yet to lose a branch on my plant at home. Very old plants lose branches as a matter of course, changing from a cone-shaped tree to a tree with a rounded canopy at the top of a long trunk, though that's not something you'd have to worry about indoors.
Feeding: Unless I hear otherwise, I'm going to assume that the usual houseplant feeding routine applies here: a little shot of 20-20-20 every three months or so, possibly skipping winter, should be good.

It seems to be normal for leaf size to vary like this.

As indoor cultivation goes, I'm not going to argue that it's the prettiest or easiest tree. It isn't going to give you flowers, the leaves are sharp if you encounter them at the wrong angles, and it's not likely to become the nice symmetrical plant that its relative A. heterophylla is. But you could do worse, and what it lacks in aesthetics it sort of makes up for in history and strangeness. History and strangeness can be their own beauty, sometimes.

Seen from above.

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Photo credits: As attributed in text.

References: http://www.pfaf.org/database/plants.php?Araucaria+bidwillii
http://www.cityofdunedin.com/city/?page=bgplant_bunya
http://www.conifers.org/ar/ar/bidwillii.html
http://tree-species.blogspot.com/2008/06/bunya-pine-araucaria-bidwillii.html
http://en.wikipedia.org/wiki/Araucaria_bidwillii

¹ One site I visited attributed this to A. bidwillii being, basically, ugly compared to A. heterophylla, though they didn't phrase it quite like that. In any case, I think it was uncalled for.
² Petrified Forest National Monument, in Arizona, contains hundreds of acres of petrified Araucaria logs. These are actually a bit older than most: they date from the late Triassic period, which means the trees in question died more than 200 million years ago. [Sidenote: the identification of the logs as Araucaria is somewhat contentious, with some scientists preferring Araucarioxylon instead. The two aren't interchangeable, but they are related, which is close enough for me. And also, there are actual fossil Araucarias which aren't controversial, in South America.]
³ They're actually a little bit more closely related than that, because they're also in the same section, section Bunya: I'm a little unclear on where sections fit into the hierarchy of species, genus, family, etc., but it looks like a subdivision somebody stuck in between genus and species: all Araucarias are related, but some are more related than others. Why is this a distinction worth making? Damned if I know. But to return to the original point: although the fossil Araucarias known from South America are in fact not Araucaria bidwillii, being instead an extinct species named A. mirabilis, Araucaria bidwillii is their closest living relative. And yes, there are people who study fossilized plants as an occupation (called paleobotanists), and I'm willing to bet you large sums of money that they take this kind of thing very, very seriously.
⁴ You know, I tried coming up with original jokes, but the only one I came up with on my own was the McCain one, and it kind of writes itself, really. For the rest of them I had to resort to modified Yo Mama jokes, which is not as easy as it sounds. Very few jokes in the Yo-Mama-is-so-old mold can be adapted to fit trees.
⁵ Technically, they expanded the boundaries of an existing park, Bunya Mountains National Park, which had been established in 1908.
⁶ Though the cones are individually either male (produce pollen) or female (produce seeds), the plants themselves produce both kinds. I ran into a contrary claim during research, saying that the species was dioecious (having separate male and female individuals, as for Rhapis excelsa), but I believe this is not true.
⁷ Before settling on "caveman" for the "person" for this species, I was considering "grandma," because grandmas are the only people I could think of who are very old and routinely try to kill you by giving you too much food. Caveman won out because this is too spiky of a plant for "grandma" to seem appropriate, plus cavemen are that much older and are known to enjoy bonking others on the head, which [most] grandmas are not.
⁸ After researching for this post, I suspect that at least some of the problem was because I repotted it shortly after getting it home. Young plants are said to have fairly delicate root systems, so I may have set it back inadvertently.
⁹ Incidentally: Pierson's, in Cedar Rapids, at one time had an Araucaria bidwillii about three and a half or four feet tall, for which they were asking $59.95. This is a pretty damn good price, considering how much time and work it would take to grow one to that size yourself. The only catch is that I'm not positive that Pierson's stayed above water in the recent floods: they were close enough to the river that I worried, but far enough away that I haven't yet called to check up on them. Since I saw a Pierson's delivery van in Iowa City yesterday (which would have been notable even without the flooding), I'm guessing that they survived, but again, I haven't called to ask.