Wednesday, June 24, 2009

Hairy Boonaree

Alectryon pubescens
I was rather pleased with this hairy boonaree fruit which I found on a little tree in Franke Scrub, Cawdor, yesterday. They don’t fruit often, so it was good to be able to see its velvety capsule - the thing which distinguishes it from the very similar common scrub boonaree, A. diversifolius (see February 08)
The hairy boonaree is at the southernmost edge of its range, on the Darling Downs, and is not very common here.
Both these boonarees have very variable leaves, and similar showy “rooster’s eye” fruits. The leaves (and fruits) of A. pubescens are larger, but it can be difficult to be sure which of the two plants you’re looking at, as there’s considerable overlap.
Like all the Alectryons they have these bright red "cockscomb" arils, which swell when the fruit is ripe, bursting the seed capsules in half, and throwing off the little "cap". The beedy little rooster's eye seeds are almost completely surrounded by the aril, whose bright colour attracts the birds which eat the seeds and then "distribute" them to grow away from the parent tree.

This huge leaf was unusual even on the tree where I found it last year, on Mt Kynoch. I didn’t confirm the ID at the time, but it is probably another specimen of A. pubescens.

Saturday, June 20, 2009

Rock Felt Ferns

Pyrrosia rupestris
We often see these little ferns growing on rocks and trees in the rainforests. Sometimes people mistake them for orchids, but here is one growing out at Gowrie Junction which clearly shows that it is a fern. It has these little brown spore- patches on the back of its fertile leaves (or “fronds”).
All ferns have two kinds of leaves, the infertile ones having no spore bodies. In many species of fern, the fertile fronds are a different shape from the infertile ones. Sometime the difference is hardly noticeable - they are just a bit longer and thinner. In the case of these little ferns, they are so different from the little round infertile leaves that they could be mistaken for the leaves of a different species of plant.
They are interesting, botanically, in another way, too. Green plants create their own food by photosynthesis. Using sun-power, they convert water and carbon dioxide into body mass. This means that they absorb carbon dioxide through their pores (“stomata”) whenever there’s enough light for the process.
Pyrrosia ferns are unusual in that they can absorb carbon dioxide at night and save it up for the daytime. They can therefore leave their stomata closed in the heat of the day to prevent themselves from losing water - a knacky trick which is the secret of their drought hardiness.
Rock felt ferns are quite easy to establish on trees in our own gardens. The best way to do it is to choose a tree with permanent bark, then wait for a light shower of rain, one which will partially wet the tree trunks without saturating everything. Examine your target tree, and note where the flow patterns of the water make wet patches. Choose a wet spot which faces east or south, so the little fern won’t have to cope with too much sun of drying wind, and attach the fern there.
Meanwhile, keep an eye out for spore bodies on the backs of the fronds of all kinds of ferns. There are a lot of them about at this time of year, and they are an easily overlooked delight, each species of fern having its own characteristic pattern.

Saturday, June 13, 2009

Black Plum-Ebony in Boyce Gardens

Diospyros australis
This morning, to my delight, I found this little ebony tree in Toowoomba City’s only remnant patch of rainforest. Friends and I searched for it without success last year, and were disappointed not to find it, as it is one of the important indicator species of that particular type of rainforest.
It is not so very difficult to identify, because of its dark green leaves which are strongly “two-ranked”, (in two flat, parallel rows), on branchlets which tend to zig-zag. Today, however, any doubts about identification would have been dispelled by the ripe black fruits, in their little cup-like calyxes which are typical of the ebony family. This was a female plant, of course. I didn’t find any males about, but there must be some there as this female was able to set fruit.
Plum ebonies are one of our five local species of true ebony, all of which are related to the Indian tree (Diospyros ebenum) which produces the famous, hard, black timber traditionally used for piano keys. Another well-known ebony is the persimmon (Diospyros kaki).
Our ebonies also have beautiful heartwood, and edible fruits.
I haven’t actually tried eating them, as I don’t expect to like them much. They are probably astringent unless very ripe, and might not ripen unless stored and picked. If you really want to try one, do make sure you don’t waste the seed. There are not enough of these trees around Toowoomba, despite it being the plant’s original habitat.
As with most rainforest seeds, this one probably loses its viability quickly. The trick is to not let it dry out. If you can’t plant it at once, keep it in a plastic bag until you can.
Plum ebonies can be grown as small trees, and like to spend their early lives in a shady place, but can eventually emerge, growing in the sun where their shady canopies are appreciated. They would also make a lovely hedge, in a shady spot. Their dense canopies make them favourite bird-nesting sites, and fruit pigeons love the fruit.
These are drought resistant, frost hardy plants, also suitable for fire-retardant planting

Pretty Pants

Hypoestes floribunda

We found just one of these plants at the Bunyas last weekend, by the car park at the Carbine’s Chute walk. They were obviously very happy with their shady, forest-edge site.
It’s a soft little sub-shrub which could be a could be a particularly useful garden plant.

It flowers well in the shade, preferring a well-mulched site. Though looking its best in damp soil, this is is actually a remarkably drought hardy plant.
These frilly pink flowers appear in early winter, just at the time when so many other flowers have given up until spring.

Crows Apples

Owenia venosa
These fruits by the roadside in Connolly’s Road, Geham, are starting to colour up beautifully. Crows apples are typically plants of dry rainforest, of the kind where hoop pines grow - but here they are remnants, in a very exposed site on an ironstone ridge. There may once have been an extensive patch of dry rainforest there. The bower vine flowering with them is also a lovely specimen, with unusually white flowers.
Crows apples are obviously desirable garden plants, being small, shapely trees with dense shady canopies and these pretty fruits. They say you can eat them, and they taste sour - but I’ve never really wanted to try.
The plants will sucker if pruned, and there is evidence of this at the Connolly's road site where some earth-moving machinery would have interfered with the natural, single-trunked growth habit of some of the plants. This characteristic means that the plants could be grown as a good hedge or windbreak.
The seeds are famously difficult to propagate, and no-one seems to have found the secret of consistent success. They tend to remain alive and healthy for a very long time, but refuse to germinate.
One hint is that they tend to come up in scrub turkey’s nests. Perhaps burying them in compost would help? Leaving them there for years might also be part of the secret.
Some people suggest that finding very old fruits under a tree - ones which have worn down, with time, to a smaller size with thinned seed coats, will help. Sandpapering the fruits - and passing them through a pig - have also been quoted as methods which methods which have achieved success, but the failure rate is still high.
If you’ve had success, I’d enjoy hearing from you.

Friday, June 5, 2009

Queensland Silver Wattle

Acacia podalyriifolia
Every year, just as winter’s cold fingers start to remind us that there’ll be a few miserable months ahead, this pretty wattle always burst into glorious flower to cheer us up.
It’s a pity that the prettiest wattles are short-lived. This one is past its best at about six years old, and I prefer to remove them from the garden when they’re younger than that. I can enjoy them at their prettiest age - the first two or three flowerings - but prefer to avoid the chore of removing full-grown straggly ones.
Every year, just a few seedlings come up in my garden. They are not so numerous as to be a nuisance, but there are enough of them for me to choose some well-placed ones which I leave to grow.
The outstanding foliage is suitable for floral arrangements, looking lovely with white roses in a wedding bouquet.
These plants do like well-drained soil, where they’ll outlive the toughest droughts, and some hard frosts.

Birdwood Sanctuary Estate

I am delighted to find that there are developers who don’t want to knock down all the native plants. I had a look at the Birdwood Sanctuary Estate at Gowrie Junction, west of Toowoomba, last weekend. The development has not only saved as much of the local dry rainforest as possible, so buyers of the 1-acre blocks can have some on their properties, but has set aside a large area of it as a reserve, so that most of the properties will have it coming right up to their back boundaries.
The rainforest is of the local type known as “semi-evergreen vine thicket”, and contains an impressive variety of the small trees typical of this type of “scrub” - trees which are deep-rooted, tend not to interfere with paths and housing foundations, and are the best possible kind of plant for a “waterwise” garden.
The ideal garden for this area would use the same species to extend the theme around the new house.
The estate is in Baxter Road, about 5 or 6 k from Gowrie Junction. To find it , you head west from the Gowrie Junction roundabout, turn right into Gowrie-Lilydale Road, take the first turn left into the road to Kingsthorpe and Glencoe, and the turn left again, into Baxter Road.

Prickly Lixy

Alyxia ruscifolia
I photographed these little “chain fruits” at Birdwood Sanctuary Estate last weekend. The plant was hidden deep in the scrub, so it didn’t show its potential - which it certainly has - as a very good hedging plant.
Its leaves are like little daggers. This is a plant which would definitely help keep intruders out, if used as a hedge in a garden. It also helps keep predators away from little birds, so is a good choice for a bird-friendly garden.

Its white flowers, which appear for a long period in spring, have an outstandingly lovely perfume.
It’s hardy to both drought and frost, and will grow in full sun or deep shade.