Thursday, December 4, 2008

Bumble trees - our local native capers

Capparis species
This is one of my favourite trees. It’s a venerable old bumble tree, Capparis mitchellii, out at Lake Broadwater (west of Dalby). The photo shows the break in the canopy, where perhaps another tree once grew. Capparis species often start life at the foot of another tree, appreciating the shelter, and behaving like climbers, using their thorns to climb up their neighbour.

Whatever the reason for it, this gap is now a favourite shady resting spot for kangaroos.

Here are some unripe fruits from the tree, which is the largest-fruited of the native capers. (Note also the butterfly eggs in this photo).

Overripe fruits turn orange, and smell like rotten oranges. They have earned the tree the common names of "Native Orange", "Wild Lemon", and "Native Pomegranate", although they are really like none of these things.
They are edible, when soft, but still green in colour.

Capers are one of our most valuable butterfly hosts. Five local species of caper butterflies breed on nothing else, and the plants can be spotted from afar because of the fluttering host which surrounds them. The commonest of these butterflies, known simply as the “caper white” (Belenois java - see photo at right) is a strongly migratory butterfly, often very conspicuous for its large numbers spread over hundreds of square kilometres, in early summer. The reasons for this migratory habit are not known, but may simply be the result of overpopulation in the area they are leaving. The other four species are very similar in appearance, and all are frequently seen together.
The caterpillars often infest their host plants to the extent of eating off every leaf and all the new shoots as well. The result would be not pretty, except for the beauty of the fluttering host surrounding the plant. The caper trees are used to it and bear it all stoically, bouncing back after every season with the renewed freshness of a plant that’s been skilfully pruned. One of the host plants, the caper relative called broombush (Apophyllum anomalum) saves time by being leafless in the first place.
The Caper White butterflies are a favourite food of Blue Wrens - another good reason for growing Bumble trees. The dense and sometimes prickly canopies of the tree capers are favourite nesting sites for a number of small birds.
We have five local caper species. Three of them are small trees ( and Capparis arborea, C. loranthifoliaC. mitchellii). Then there are their relatives, the prickly little bumble-bush (C. sarmentosa) and a scrambling shrub of the Darling Downs called “split jack” (C. lasiantha). They all have lovely white flowers, which, with their four petals, resemble butterflies themselves.

Fruit formation is a curious process. The dying flower puts out a fruit “stalk” from its centre, as though it’s holding its fruit away from it, at arm’s length.

All the species are very prickly when young, with the characteristic paired spines situated where the leaf-stalks meet the stems. The juvenile leaves are very different from the adult ones, so it is difficult to identify this little plant (at right). It grows tucked up next to the trunk of a scrub wilga, in Franke Scrub near Highfields, where there three different Capparis possibilities.
They lose their prickles to a varying extent as they age. The little C. sarmentosa never loses them, and at the other end of the spectrum, the silvery-leaved tree from the eastern slopes of the Range, C. loranthifolia, can be completely prickle-free when it’s mature.
Capparis mitchellii is the best tree for the blacksoil, and other alkaline to neutral soils. Its range overlaps with C. arborea, on the edges of our redsoil. All the local native capers are very drought resistant, but C. mitchelli is the best for frost resistance.
The capers you buy in little bottles in the supermarket are the flower-buds, pickled, of Capparis spinosa, a shrub native to the Mediterranean region. There seems to be no reason why buds of our native species couldn’t be used for the same purpose. If you like capers - go for it! (But do plant your own trees if you want to do it in any quantity. Australia is long past the stage where wild harvesting of bush tucker can be considered ethically respectable.)


Anonymous said...

Just to make sure, have you actually tried the fruit of C. mitchellii? And from more than one tree in case it differs like Gala apples differ from Granny Smith apples, etc.? I am very curious because living in California I am always on the look out for new fruits that can handle tough climates (high heat, occasional freezes, low water) with unique flavors. I think you Australians may have a special fruit right under your noses but alas I don't have the opportunity to sample the range of C. mitchellii to see if there are superior trees already growing. I'm looking forward to your reply and/or any additional information you can supply.
Tynan Wyatt

P.S. Next time any of your M. mitchellii are in fruit could you consider sending me some seeds? I have seed import permits and would pay the mailing costs both ways gladly. All the best!
California Rare Fruit Growers

Patricia Gardner said...

I haven't eaten it, Tynan. After the smell, the motivation just wasn't there!
Re exporting seeds: I'm sorry but the answer is no. I'm afraid I really haven't any interest in sending seed internationally. My enthusiasm, as you can see from this blog, is in plants growing in their own place in the world.

Unknown said...

Wow, delicious fruit and yes I have come across variations from mustardy to sweet orange. I live in the South Burnett region. We also have Capparis arborea growing along side of the mitchellii, the arborea is covered in fruit this year and I plan on propagating. Any tips?

Patricia Gardner said...

Hello Daniel.
Sorry you had trouble posting your comment. Comments sit in limbo till I get round to looking at them and deciding whether to let the comment through, and I've been busy with family and Christmas etc. (This filtering process is to stop undesirables from advertising nasty items on my blog, which is what can happen. There are some greasy people out there.)
It's good to hear from you, and I'm glad to hear you're finding nice fruit to eat. There seems to be only a small period between underripe and overripe, so it's possible to miss a year's crop.
It's interesting that you have arborea growing alongside mitchellii. It only happens along the edge of their ranges.
They are easy to grow from seed, provided you have nice, ripe seed and plant if fresh. Get as much of the flesh off as you can, by soakinf the seed ror a few days, byt you will never get it all off, which doesn't seem to matter.
The small plants can be very slow to grow for the first few years, though mulching and watering helps. You may find you want to check for butterfly eggs for the first few years. Butterflies are lovely, but their babies can be a problem when the plants are only infants, themselves.
Best of luck!

Unknown said...

There is a similar species in NW Qld which is favoured by sheep and cattle in a dry time. The stock, in their turn, have killed most of it by over grazing. When I dug post holes near a bush, I was down to 4 feet deep and finding soft, fragile storage roots 2 or 3 inches wide, which may explain it's ability to maintain green shoots in a drought. No doubt when such roots rot away they leave a handy cave for ground animals to inhabit. The flowers are typical, like pictures published of other capparis sp. Leaves are rounded and fleshy. Fruit is fragrant and pulpy when ripe and favoured by little black ants.

Patricia Gardner said...

Hello Ian.
That's really interesting.
I believe Capparis loranthifolia, which is a little tree, grows out there. Perhaps this is what you have. I think you would also get a scrambling sort of Caper Vine, (Capparis lasiantha) which I know as Split Jack, but it may have several common names.
All the native capers all have rather similar flowers, though in varying sizes. They also all have edible fruits. Not necessarily really worth eating, but it will do you no harm to try. They probably need to be very ripe, to taste good.
Isn't it interesting that stock like to eat them, despite their prickles? This is typical of the trees that are classified as "dry rainforest" type, despite being a long way from rainforests. They all tend to be edible and nutritious to herbivores, and often with prickles which they have evolved to prevent themselves from being grazed to death.
The deep roots don't surprise me. this is another typical "dry rainforest" survival trick, and they may well actually go much deeper than your post holes. In theory their chance of regrowing should be good, and they have obviously survived grazing by native herbivores for millenia.
It's a pity that our introduced herbivores are just too tough on them. We can do with plants that survive being grazed, without actually dying.

Marilyn said...

Hi I am very new to this. I have just found several Bumble Trees on my property West of Chinchilla. These trees would have been pulled at some time long before we bought the block. Since the rain they are thriving and several are in full fruit. We only realized we had them when we noticed the sheep liked a particular part of the paddock. They are grazing them up as far as they can reach.
How easy would it be to get more to grow?? What can the fruit be used for??Thanks Marilyn Hughes 19/10/18

Patricia Gardner said...

Hi Marilyn.
Nice to hear from you.
Did you see my second post on bumble trees? It has a bit more information about them. (To find it type the word bumble into the white search box at top left.)
I find it is quite easy to get the seeds to grow, so long as they are ripe (or overripe). I like to clean them up a bit, by soaking them overnight and rubbing them around in a sieve to get some of the flesh off, but this might not really be necessary. Don't let them dry out at any stage, but plant them on a pot straight away and look after it well. Not too wet, not too dry. Once they start to sprout, you can pot on as many as you think you'd like to grow, or just put them in the ground straight away. I like to use tree guards to give them just a bit of shelter. And as you've already noticed, stock love to eat them despite the prickles, so they will need to be protected from whatever animals are about.
They like a fairly deep hole (just to break up the soil), but it doesn't need any width. A post-hole digger is a useful tool, but a little trowel does just fine, too. Water well, especially in the hole before you plant. (Well soaked water crystals are good to put below the roots, just tickling their toes.).
Remember that nature doesn't space plants out widely. You will get canopy more quickly if you plant more of them, and put them in groups of 3 or so, as close together as 30cm.
I find the small trees are slow, but others don't agree with me, so it may be a matter of how much watering they get in their first year. They don't actually need any watering once they have settled in and grown a few new leaves.
Don't worry about caterpillar damage once the plants are past the very tiny stage. The plants always recover from it, so you might as well not fuss.
I have never tried to use them as food, so will be interested to hear the results of any experiments you might try.
All the best.

Unknown said...

Hello. Do you know where I can buy a CM tree in the Warwick or Toowoomba areas? Not after seeds if possible. Thanks. Phil.

Patricia Gardner said...

Hello Phil.
They have some small seedlings coming on at the Crows Nest Community Nursery. You could visit on a Thursday morning when it is open, or contact the nursery manager to arrange for an order to be picked up at a time that would suit you, in Toowoomba. You do this by ringing the Toowoomba Regional Council and asking for the Crows Nest Community Nursery manager.