FRIENDS of the AUSTRALIAN NATIONAL BOTANIC GARDENS

The Western Mallee (Section 100)

Anne Phillips, Member of Growing Friends

I'd like to draw your attention to a fascinating little pocket of the Gardens situated above the nursery. Section 100 was established for the express purpose of holding mallee eucalypts from the arid areas of Australia, that were previously sited along the edge of the Eucalypt lawn where they received too much irrigation, with undesirable consequences.

Creating this garden began in about 1990, first by excavating a lawn area and preparing a drainage system three metres deep. The area comprises washed coarse and fine river sand. A couple of years later the retaining wall was built to contain soil run-off, and this section consists of crushed granite and eucalyptus mulch, fine sand and lime, a bit of humus and zeolite to hold nutrients. Several truckloads of red soil from Roto near Griffith, NSW, were mixed with this.

At this time the ANBG was moving away from the use of chemicals to control insects, and this field being of interest to Greg Flowers, horticulturalist at the Gardens since 1987, he embarked on a study of biological control, selecting three Eucalyptus ligulata in Section 100 for the trials. In the early stages these plants were prone to a fierce infestation of scale, Eriococcus tepperi (identified by the Zoology Department of the ANU). Now, with a healthier microclimate, this is rare. The reading of this study into the insect ecosystem is indeed interesting, but I won't go into detail here.

The approach to Section 100 is up the tar road beside the nursery. On your left are a variety of mallee eucalypts, but on the right your wonderful discovery tour begins. You'll see lots of Eremophila species, but what caught my eye was Eucalyptus eremophila (eremophila meaning 'desert loving'), the Sand Mallee. It has the most unusual paw-like stems, about three centimetres long, flattened with a zigzag tip, where the pendulous buds form. This species is from south-west Western Australia.

A huge Melaleuca decora stands sentinel over the horseshoe-shaped sleeper path.

Late one afternoon in May, I saw Eastern Spinebills feeding on the nectar from a few remaining flowers of the rare and endangered Eucalyptus crucis subsp. crucis, the Southern Cross Mallee. The bark is most interesting with its curling strips revealing smooth coppery-red underbark (this type known as minniritchi bark). It is a small, sprawling mallee, again from south-west W.A, found always on, or around, granite rocks.

Eucalyptus crucis subsp. cruci                                          Photo by D Grieg

Leptosema daviesioides                                                         Photo by M Crisp

Round the corner of the path you'll find the Upside-down Pea Bush, Leptosema daviesioides (similar to the genus Daviesia). It's low to the ground and the orange/red flowers form a crown around the base of the plant while the foliage sprouts out over the top.

Nearby, on the gully side, is Grevillea centristigma covered in yellow/orange flowers set amongst soft hairy leaves.

Expected to be flowering at time of publication of this newsletter (Alex George's Banksia Book says June to January) is Banksia coccinea, Scarlet Banksia, though it can be reluctant to flower in cultivation.  The flower head is round and squat, with the flowers actually grey, contrasted by the scarlet styles. Robert Brown in 1801 collected the first specimen from King George Sound, W.A.

Banksia coccinea                                              Photo by D Grieg

Close by, another striking plant, Hakea victoria, Royal Hakea, looks like it belongs in the sea or the veggie patch. Its distinctive feature is its leaves - fiery red/orange near the stems changing to green with orange veins towards the outer edge. New growth is yellow to green with yellow veins. Dazzling when the sun strikes the plant and the leaves really do resemble flames. It's the best specimen of its kind around these parts, though there is another good one at Burrendong Arboretum near Wellington, N.S.W.

There's always more to discover at other times of the year, so keep visiting Section 100.

Illawarra Grevillea Park

Brian Buckley, Volunteer Guide

Bulli Pass at first seems like all the other roads along the east coast that lead from the tablelands to the seaside. It is, however, less bendy and a lot steeper than many, with a spectacular 1:6 gradient. Another difference is a lovely garden set into the hillside almost hidden from view behind the Bulli Bowling Club and the Showground.

The garden, Illawarra Grevillea Park, otherwise known as Slacky Flat Park, was the site chosen for a visit by a group of Friends on Saturday, 3 May. The park is staffed entirely by volunteers and only opens its gates to the public six times a year. The small number of volunteers has managed to minimise the formalities and devote their time almost exclusively to maintaining the park. They receive assistance from the Bulli township, local businesses make donations in kind and the Grevillea Study Group of the Australian Plant Society provides generous assistance.

The main gates open onto a courtyard where volunteers had plants for sale. Some of our group made purchases while others thought that Canberra might be too cold for these varieties.

Ray Brown made the group welcome and described the ten-year history of the park and gave a quick rundown of how the plants are maintained. A map was provided and we set off on our journey of discovery.

Photo by B Buckley                            

The first part of the gardens is an area on a slope leading up to a knoll where an historic chapel has been rescued from a dismal fate and now serves as a tea and coffee shop, bookstall and picture gallery. There are no large trees on this slope and the zigzag path is lined with plants soaking up the sunshine. As the name of the park implies the main plants in this area are Grevilleas.

The large size of the flowers and their range of colours - yellow, orange, red and even mauve - brought plenty of cries of delight from the group. The only disappointment here was the absence of labels. The best you could do was take a mental picture of one or two species and look at the picture gallery in the chapel and attempt to make a match.

From a picnic area the path led into the rainforest plantings. Here the humidity was palpable, supported by recent rains, an irrigation system and the nearby sea. This area is cultivated and features well-made paths leading through fern laden banks. The tall trees form a nice canopy and the dappled sunlight drifting through makes a pleasant scene. This is, however, only a preview of the delights that await those who are able to venture to the next stage.

Through the back gate of the park the trail leads to a gully running into the hillside under Bulli Pass. Here lies a real rainforest. The only improvements made are a path and narrow gates designed to stop anything but people getting through.

The path makes a loop through the forest and is named the Vine Forest Walk. Unfortunately the path is dirt, rough, twisty and at times quite steep. It crosses Slacky Creek twice and the walker has to step from rock to rock. Not everyone in the group could manage this part of the park. For those that could, the tall palms, cedars, various fungi and, of course, the vines all combined to make this a sensational part of the day.

Grevillea Park occupies 40 acres and there was no difficulty filling in the three and a half hours we had there.

On the trip back home we travelled from the coast across to the Hume Highway via Appin. In one part the road was lined by hundreds of Doryanthes excelsa. This will be quite a spectacle when they are in flower. I look forward to hearing a report, or seeing pictures, from the next group to travel down that way.