I'm a little wary of following up a deeply taxonomic post on a local native orchid with something as equally esoteric on a native clematis. But clearly not wary enough. I was also encouraged by this species earning a Flowering Friday spot last week.
In August, the first month of spinter, the natural bushland around Melbourne (below, at St Andrews) and the bushland replanted around Long Island in Melbourne Gardens (above, next to the purple sarsaparilla), became cloaked and occasionally choked with light yellow flowering Clematis decipiens.
Back in the day, let's say 1996 when the relevant volume (3) of the Flora of Victoria was published, there were three native species of Clematis in Victoria, and one or two naturalised here and there. Neville Walsh and I edited the volume, and Neville wrote up the account for the family Ranunculaceae (which includes this genus, the buttercups - Ranunculus - and few other odd species in odd genera).
At that time, this local harbinger of sprinter with relatively small leaves was called, conveniently, Clematis microphylla (micro meaning small, phylla meaning leaves). There were two varieties, one called leptophylla in East Gippsland, and one all over the State called microphylla.
Fast forward two decades, and VicFlora (the online version of the Flora of Victoria) records five native species of Clematis recorded for Victoria. One of these is that East Gippsland variety, elevated to species level - Clematis leptophylla. That makes four. The fifth is a species called Clematis decipiens, chipped off the old Clematis microphylla variety microphylla, leaving that entity - now a full species - as something growing along the coast and drier inland west of Melbourne.
In bushland to the north-east of Melbourne, and at Long Island in the Melbourne Gardens where we have tried to introduce plants indigenous to the area, you would expect Clematis decipiens. 'Decipiens' means deceiving, and is a reference to this species being for sometime hidden within the variable Clematis microphylla.
So geographically the plant illustrated here would be Clematis decipiens, and if you key it out using
VicFlora it pretty much confirms that identification. I've extracted here the critical things to look for;
Clematis decipiens: Adult leaves with 12–15 leaflets; margins entire or 3-lobed; terminal leaflets ovate to lanceolate, 1.2–4.5 cm long, 1.5–5 mm wide.
Clematis microphylla: Adult leaves with 9 leaflets; margins entire or appearing toothed on incompletely divided leaves; terminal leaflets linear to ovate, 0.8–6 cm long, 0.3–1.2 mm wide.
You'll find counting the leaflets a little tedious and not entirely satisfying. They are even harder to photograph in any meaningful way! You'll have to take my word for them mostly having 3 groups of 4 'leaflets', or sometimes an extra lobe pinched off a the side. The size and shape of the terminal leaflet is, as you can see, not a clear distinction and can be quite variable.
Anyway, I'll stick with Clematis decipiens, the deceiving one. The Indigenous Flora and Fauna Association (IFFA) website tells me that this species is 'an attractive place for nest building' and when in flower it attracts 'a variety of insect life including small flies, a bonanza which is appreciated by small insectivorous birds at a difficult time of year'.
Plants have either male or female flowers, not both. These are male flowers in the picture above, each with a spray of stamens (topped by pollen-bearing anthers, unopened at top right). Below are female flowers, with a column of female receptive bits and between them and the petals, some dud male parts which we call staminodes flaring out at the sides. The IFFA page warns that 'if a female plant is grown, seedlings are likely to appear in various corners of the garden.' That has certainly been true around Long Island.