Botanic Gardens Trust, Sydney, Australia


Never smile at a crocodile - collecting seed in the Top End

by Greg Bourke, Senior Supervisor Garden Services, Blue Mountains Botanic Garden Mount Tomah

With the Biome Top End project underway for the Royal Botanic Garden, Sydney, collection of seed for the display could begin. Having made numerous trips to the Top End to study and photograph plants, I jumped at the opportunity to extend my trip in late April 2013 to the Darwin/Kakadu area (Pangkarrang as it’s known to the Jawoyn people) to collect the ‘small stuff’ or filler plants that are an important part of any display. My primary interest is in the small stuff, mainly carnivorous plants (Byblidiaceae, Droseraceae, Nepenthaceae and Lentibulariaceae) and trigger plants (Stylidiaceae) of Australia so I spend much of my time in the scrub - level to the ground!

Seed collecting is a challenging task anywhere but the Top End provides additional obstacles. Access is often an issue as much of the region is remote and after a drier than usual dry season, late March to early April 2013 saw an unusually high rainfall. This prevented access to the majority of the sandstone escarpment with many roads still closed. The effect of this on the flora was exaggerated in the east of Kakadu National Park where many of the annual herbs had either finished flowering and completely disappeared or were just germinating. Daytime temperatures reached the early 40s on most days while the humidity remained in the 90s.

As many of my target species were to be found in and around swamps and billabongs there was also the risk of running into a salt water crocodile (Crocodylus porosus) which are common in the region. As the waters recede so do the crocs (usually) and authorities relocate the stragglers in preparation for the busy dry season. I was informed by a ranger whilst up to my waist in Fogg Dam that ‘there’s still one in there’. He’s about 4.5 m long!’ he added. Naturally I finished shooting my images at that site from the safety of the bank.

Despite the challenges of the season, weather and fauna I was able to make some valuable collections. Good quantities of seed were available in the Howard River catchment area which was made available to me by land owner Power and Water. Some of the standout genera in this area include Drosera, Gomphrena, Goodenia, Spermacoce and Utriculara.

In Kakadu National Park I was able to collect seed of some interesting herbs and shrubs, several of which were important to the local Aboriginal people - members of the genus Cartonema and Tacca leontopetaloides with their edible tubers, Grevillea dryandra with its honey sweet nectar and Grevillea decurrans with its edible seeds and timber valued for carvings.

With its ancient landscapes and vastly different seasonal changes, the Top End of Australia is visually spectacular. This initial collection of over 60 species is just the beginning of what will be an amazing and colourful display of Top End flora in the heart of Sydney.