Plant of the month 06/2021: Eucalyptus chartaboma

After our wonderful outing to White Mountains National Park, it was impossible to pick “the best” among many fascinating plants we saw. Instead, our Plant of the Month is “the biggest” of our weekend discoveries.

Photo: Julia Hazel

Eucalyptus chartaboma is not widely known, although it is a Queensland endemic. Its scattered distribution in north Queensland includes the western section of White Mountains National Park which we visited on the second day of our trip. Many thanks to Peter for introducing us to this area and pointing out a number of species new to most of us.

The scientific name is derived from Greek (charte, of paper and bomos, base) and refers to thick papery bark covering the lower part of the trunk. The distinctive bark is also reflected in the tree’s common name, Queensland woollybutt.

Photo: Julia Hazel

Our visit was outside the flowering period of Eucalyptus chartaboma (Jan to April) but we were impressed by its heavy woody seed capsules. The “giant gumnuts” we found were just slightly smaller than the maximum size recorded, 75 x 65 mm.

Photo: Julia Hazel

Hopefully on a future visit we might see the brilliant orange flowers of Eucalyptus chartaboma. In anticipation, we can enjoy John’s photo below, taken in March some years ago.

Photo: John Elliott

Eucalyptus chartaboma looks very similar to some closely-related species in the Kimberley and Top End of NT. For botanical details see EUCLID Eucalypts of Australia online

Drosera adelae – a true North Queenslander

By Hugh Sweatman

While Australia is home to 117 species of sundew, representing about 50% of all recorded species, the centre of that diversity is southern Western Australia. Atlas of Living Australia lists 21 species in Queensland; three of these are endemic to rain forests of North Queensland and have very limited distributions.

Drosera prolifera is only known from canyons near the summit of Thornton Peak behind Cape Tribulation, while D. schizandra is only known from the slopes of Mt Bartle Frere. Both these species are considered “Vulnerable”.

D. adelae is only found in the hills behind Rockingham Bay and on Hinchinbrook Is. It is listed as “Near threatened”. I found large patches of this species along the banks of a rainforest stream north of Ingham, photo below.

Habitat of Drosera adelae Photo: Hugh Sweatman

In early November, the plants were flowering, with the flower heads showing a characteristic unfurling growth.

Drosera adelae flower head  Photo: Hugh Sweatman

The leaves are much larger than those of other common Drosera spp that are found near Townsville. They have “tentacles” on their upper surfaces but all except newest leaves seem to lack the sticky “dew” – perhaps washed off by the high rainfall. Rain being one predictable hazard of rainforest life, it has been suggested that D. schizandra, which lives in one of the wettest locations in Australia, may be abandoning carnivory.

A patch of Drosera adelae Photo: Hugh Sweatman

In spite of its “near threatened” status, D. adelae is apparently easy to grow if one can maintain high humidity and a diet of tiny flies, and it is widely cultivated by carnivorous plants enthusiasts.

On a visit to the carnivorous plant display at Kew Gardens a few years ago, I was surprised to see D. adelae given pride of place, next to a sign that informed the public that there was no “Feeding time” as such for the carnivorous plants …

Plant of the month 05/21: Drosera adelae

Our P o M for May is Drosera adelae, a “true North Queenslander” highlighted in Hugh’s presentation at our recent meeting.

Photo: Hugh Sweatman

Like other Drosera (about 150 species worldwide, commonly known as Sundews) D. adelae has mobile glandular hairs on its leaves, used to trap tiny insects from which the plant absorbs nutrients.

D. adelae is the southern-most of three Drosera species endemic to Queensland rainforests. Read more in Hugh’s article here.

Plant of the month 04/2021: Jacquemontia paniculata

Thanks to Cameron for nominating Jacquemontia paniculata (Convolvulaceae) for P o M and providing his fine photos.

Photo: Cameron Atkinson

Cam found an abundant display of Jacquemontia paniculata flowers on Castle Hill early this month, April 2021.

Photo: Cameron Atkinson

Jacquemontia paniculata is a slender vine, potentially quite widespread locally, but it’s easily overlooked for much of the year. It twines inconspicuously around the stems of other small plants until its dainty lilac flowers attract attention.

Photo: Cameron Atkinson

Russell’s photo (below) was taken in April 2010, suggesting this is a good month to keep an eye out for similar displays. However, it’s unclear whether Jacquemontia paniculata flowers so abundantly at the same time each year.

Photo: Russell Cumming

Botanical details are available at www.canbr.gov.au

Plant of the month 3/2021: Heritiera littoralis

Heritiera littoralis (Malvaceae, previously classified as Sterculiaceae) was selected as Plant of the Month during our March outing, against some strong competition from the fascinating mix of species at the Palmetum.

Although this species typically grows in low to moderate salinity conditions at the landward edge of mangrove forests, two specimens are thriving beside the Palmetum’s freshwater lagoon.

Photo: Greg Calvert

The small flowers, covered in fine hairs, develop into large keeled fruits that are tough and buoyant when ripe, well adapted for long-distance dispersal by water – see photo at the bottom.

Photo: Greg Calvert

Heritiera littoralis is distinctive from a distance on breezy days because upturned leaves flash intermittently like small mirrors within the dark green canopy, in keeping with the species’ common name, Looking-glass mangrove. On calm days, the leaves create a silvery-white glow under the canopy.

Photo: Julia Hazel

There is another large specimen in cultivation at Anderson Park, as Greg reminded us. If you have a seasonally wet and boggy corner of the garden, where it’s difficult to find a suitable plant, Heritiera littoralis might be worth a try. Just keep an eye out for those distinctive floating fruits when they wash up on the beach.

Photo: Greg Calvert

Botanical details are available in the Australian Tropical Rainforest Plants database.

Plant of the month 2/2021: Fagraea fagraeacea

Fagraea fagraeacea (Gentianaceae), with beautiful perfumed flowers, was a highlight of the recent NPQ outing to Paluma.

Photo: John Elliott

This was an unexpected new species for many of us but fortunately John had spotted it a few years ago, and then spent several days working out its ID. Very convenient now, to have a quick answer about an unfamiliar species!

Photo: John Elliott

Fagraea fagraeacea is endemic to North East Queensland, growing in well developed upland and mountain rain forest at altitudes of 300 to 1250 metres.

Botanical details for Fagraea fagraeacea are available in the Australian Tropical Rainforest Plants database.

Although not known in cultivation, this would be an interesting plant to try in a cool, moist spot if you manage to find seeds.

As yet fruits have not been observed on the Paluma specimen but they are expected to look similar to those of Fagraea fagrans (photo below), an Asian species that John photographed in Singapore.

Fagraea fragrans, photo: John Elliott