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Gardens to the Rescue! Saving the Exceptionally Rare Bog Willow-herb

Confined to a tiny section of moist, moss-covered rock and receiving just the right amount of backsplash from a subalpine waterfall on the Snowy Range, a plant is fighting to survive. 

The species in question is the Bog Willow-herb (Epilobium brunnescens subsp. beaugleholei), a matted, creeping perennial herb which is endemic to Victoria and extremely rare, only known to be found at this one alpine site.

Epilobium brunnescens subsp. beaugleholei gets its mouthful of a name from renowned Australian botanist, plant collector and naturalist Clifford Beauglehole who described it in 1973. In the 60s and 70s, Cliff gridded up almost the entire state of Victoria, went to every spot and collected what he could find. He collected over 90,000 specimens – the most we know of for any Victorian (probably Australian) collector.

Though there are no detailed records of distribution, a dramatic decline was noted between 1983 and 2001 to just 12m². Given the extremely small and ever-dwindling population and incredibly niche growing conditions, there’s a massive risk that Epilobium brunnescens subsp. beaugleholei will be wiped out entirely, with threats being the usual suspects - human impact, habitat loss and introduced weeds and predators such as rabbits and deer. 

As with our other precious endangered species, it’s critical to preserve their unique place in their respective habitats, for the benefit of biodiversity, and so they can be enjoyed and studied by generations to come. 

With things looking dire, Royal Botanic Gardens Victoria’s conservation botanists Andre Messina and Neville Walsh entered the picture. Already in the area on a separate collection trip to gather seeds and plant material from rare and threatened plants, they scaled the somewhat precarious rock face to collect a small sample of a wild Epilobium brunnescens subsp. beaugleholei specimen. “The specific rock face is now relatively well known among the botany community, so we had a good idea of where to go and went to have a look and see it for ourselves”. 

As the species wasn’t flowering or fruiting at the time, Andre and Neville scraped off a sample of the Epilobium brunnescens subsp. beaugleholei in the mossy substrate in which it was growing. Once they returned to the National Herbarium of Victoria in the heart of Melbourne Gardens, they handed over the precious sample to the capable hands of Chris Jenek, a horticulturist in the nursery, hoping it could be grown as a seed orchard to enable seed harvesting for safekeeping.

With no literature to use as a guide, growing Epilobium brunnescens subsp. beaugleholei and keeping it alive was a process of trial and error. “I set it up in a nice tray of moss, and slowly, it took off!” Chris said. Chris tried a number of different techniques to nail how to grow this beauty – “I slowly learned what Epilobium brunnescens subsp. Beaugleholei likes and dislikes”. He moved specimens in and out of sun and shade, varied the amounts of water and fertiliser he was providing them with, and a range of other growing conditions. With not an insignificant amount of TLC from Chris, Epilobium brunnescens subsp. beaugleholei flowered, producing seed caps that were sown to produce more specimens, and provided to Neville, Andre, and the Herbarium team. 

The overall objective when it comes to the rare and threatened flora such as Epilobium brunnescens subsp. beaugleholei that the Gardens work with is to minimise the risk of extinction in the wild and maximize the likelihood of these species becoming self-sustaining. 

The adoption of broad-scale management techniques and the collection of important baseline data surrounding how to grow this species and germinate its seeds will also benefit many other plant species growing in association with Epilobium brunnescens subsp. beaugleholei, and provide an important public education role by highlighting broader nature conservation and biodiversity issues such as land clearing, grazing, weed invasions, and habitat degradation.

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