Logania tortuosa

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Logania tortuosa

I had encountered this plant on a number of occasions and assumed it was another of the many dry country sedges. However, one day I happened upon it again, but this time it had many white flowers and was obviously not a sedge at all and not even closely related. The leaves are minute and scale like, whilst the sedge like stems are bent and twisted, which is why it is called L. tortuosa.

Logania tortuosa is an inland species growing to around 30 cm (12") in height; it is found around 100 km (60 miles) NW of Esperance, then to Dumbleyung (further west) and from there to 130 km NE of Perth and then onto the Kalgoorlie region. A common species, but the colonies I know tend to reasonably compact, widely spaced, and locally restricted to shallow sandy soil over gravel.

The hairy centred white flowers are surprisingly large when compared to most other Logania species, measuring to 1 cm (3/8”) diameter and are scattered along the stem in small groupings of 2 or 4 flowers. The stems have approximately a dozen or so fine parallel vertical ribs and along their summit, each has minute, neatly spaced protuberances (papillae), nevertheless the plant is completely harmless and may be handled comfortably.

Flowering is recorded from September to December, which also agrees with my findings.

The Logania genus is part of the Loganiaceae family.

Logania buxifolia – Loganiaceae

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Logania buxifolia – Loganiaceae

Plants in the Logania genus (part of the Loganiaceae family) are little known outside botanical cycles, despite being relatively common and widespread throughout the country, especially in Western Australia that has 19 species, 16 of which are endemic to the state. Overall there are 35 species spread throughout Australia (except Tasmania), plus NZ and New Caledonia (FloraBase, WA Herbarium).

Logania buxifolia is a WA endemic and characterised by the small (around 1 cm or 3/8” in length) oval leaves, which resemble those of Box Trees (commonly used for close clipped hedges, etc.) and from whence its botanical name originates. Logania buxifolia is mostly found from Albany to the western edge of the Nullarbor, where usually encountered in small-localised colonies.

Locally, this species favours non-calcareous sandy soils over gravel, or on gravel alone, both habitats strongly favoured for farming and road construction and both probably impacting on this species population and distribution. It grows primarily to around a metre (3’) in height, but can exceed this on occasion in sheltered locations amongst taller shrubs.

The white flowers although small, are numerous and tightly bunched (3 cm 11/4” diameter) at the summit of branches to produce ornamental displays. The flowers are waxy, not unlike Chamelaucium spp. (Esperance Wax, Geraldton Wax, etc.), therefore preserving their floral structure and condition for lengthy periods.

This and other Logania spp. are strongly influenced by seasonal rainfall as to when they flower, so can be found fully or partially in bloom at almost anytime of the year, but with this species, late winter and throughout spring would be their usual period.

Logania vaginalis - White Spray

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Logania vaginalis - White Spray

Loganiaceae is the family name of Logania, which are shrubs distributed throughout Australia although Western Australia has the greater number, currently twenty-two. Many are unisexual where flowers of different gender occur on separate plants, but with Logania vaginalis flowers are bisexual. Leaves (when shrubs are not leafless) are opposite along the stem and the Forget-me-not like flowers mostly white and often clustered.

Logania vaginalis is a slender upright shrub, distributed from Cape Arid (110 km or 70 miles east of Esperance) around the coast to Geraldton. Growing in excess of 3 metres (10’) although mostly only half this height, it prefers the calcareous sands sometimes over limestone, but will tolerate other well-drained soils and is commonly found along coastal or near coastal roadsides in disturbed soil. The leaves of this species are amongst the largest of these plants and when young can be 10 cm (4”) in length, although shorter on mature shrubs.

The dry seed is produced in top opening capsules and spills out as the plant sways and bends in windy weather. Plants remain viable for many years, although benefit from fires or soil disturbance that will encourage fallen seed to germinate. Mature shrubs when burnt or damaged can resprout from the rootstock, so although plants often look weak and spindly, once a colony becomes established it can outlast many other species. Logania vaginalis is a  non-agressive colonising plant and will help stabilise soils after environmental disasters, but rarely interferes or restricts the growth of other species so is not weedy. Clusters of white flowers are produced from September to November.