Australian Plants online - Subscribers' NewsletterNumber 5 - June 1998Published by The Association of Societies for Growing Australian Plants CONTENTS
APOLOGIES (A COUPLE OF THEM!) As advised in a previous mailing, just as this newsletter was about to be sent, the ASGAP web site became inaccessible. Apologies to all who were inconvenienced but the problem seems to have been sorted out now. As this is the second time something like this has happened, I hope the system will be more reliable in the future.
You would have received two recent mailings which contained the entire mailing list addresses in the header. Please put this down to stress (ie insufficient red wine). If it's any consolation, about 50 messages bounced and I had to wait 50 times longer than you did for them to download. I'll be more careful in future.
1. June issue of APOL now available
The June 1998 issue of Australian Plants online is now at:
http://www.silo.riv.com.au/SGAP/apol10/ac98-2.html
and it's also linked from the main page at:
http://www.silo.riv.com.au/SGAP/
Featured in the June issue are:
2. Did you spot the deliberate error?
OK. It wasn't quite deliberate.......
If you had difficulty calling up the SGAP home page using the address listed in Newsletter 4, it was because I left the"au" out of it.
But you all knew the correct address by heart, didn't you?
3. A Big Thank You!
Thanks to the many subscribers who have volunteered to type up (is "wordprocess" a word?) articles for Australian Plants online. I even had some volunteers from overseas!
Those who have helped with the June issue are listed under "Production Team" on the contents page of that issue. I should be able to spread the load widely so, if you volunteered and haven't been asked to help yet....you will be!
4. More on Blow Flies
Chris Roberts' request for info about a plant called "Blow Fly Plant" brought several responses:
* From Karen Forde
"Try looking up 'Stapelia'. This plant has been known as the 'Rotten Meat Plant' & 'Blow Fly Plant'. "
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* From Rod Randall
"This must be Briza maxima or blowfly grass. A good pic is in our book "Western Weeds, A guide to the weeds of Western Australia" page 44-45. Other common name is "quaking grass", a widespread weed of gardens and wasteland from Shark Bay to Esperance."
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* From Horst Weber
"Could you mean Blowfly grass?
A grass of that name is mentioned in Cunningham, et al, 1981, "Plants of Western NSW", p. 67. Its botanical name is *Brixa maxima L.*, and it is commonly also known as quaking grass, large quaking grass and shell grass. An introduced, naturalised species originating closer to my home than yours, in the Mediterranean. " (Horst is German but currently resides in Ireland).
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* From Peter Vaughan (who is fascinated by pollination methods....as you will see).
"The name "blowfly plant" is often used for an Asclepsias from Africa. It has large brown flowers and they smell very good to the blowies. In Asia there are plants of the Aroid family that are pollinated by blowflies. They have some relatives in Australia, two that come to mind are Amorphophallus species from North Queensland and Typhonium brownii which I will describe here.
Typhonium brownii - single leaf, arrowhead shape. Plant spreads by underground rhizome, slowly but will cover an area a metre across in three or four years. Flower is up to 6 inches across (15 cms), funnel shaped with the "thing" sticking out of the centre. The flower is brown and is pollinated by dung beetles. Evidently they fly on dusk and at night and find fresh dung by smell. Because native dung is quite hard, the native beetles have learnt to close their wings and impact the dung with a forceful impact that allows penetration for egg laying. The flower of T.brownii is funnel shaped so any falling beetles are directed into the centre of the flower where the forceful impact allows them to penetrate to the lower reaches of the flower out of reach to other insects. Here they get their dusting of pollen if the flower is young, ie male, or they will deposit their pollen is the flower is older, ie female. Of course to attract the dung beetles the flowers smell appropriate. The interesting thing is that the flower has no odour during the day when the dung beetles are not flying, only from dusk onwards. Therefore even though some people may call them blowfly plants, the blowflies do not visit them very often, they just smell as though they should. Note: I had one growing outside our kitchen window a number of years back. I took us about a month to work out where the smell was coming from. The flowers, being brown, are not very obvious. They do look very good though. I still have them growing in a number of patches in the garden. It is actually quite a rare plant.
There is another native plant that attracts blowies in a big way, that is the starfish fungus. When fresh it has a brown liquid on the surface which contains the spores. The blowies, or probably they are compost flies (they look like blowies), feed on the brown liquid and disperse the spores."
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I suppose that the only remaining question is whether Robert Brown (if he were alive) would be particularly impressed about T brownii being named after him (if, in fact, it was).
Oh...and the email address for Chris Roberts given in the last newsletter was wrong (yes...another blunder!). It should have been:
colrob@vianet.net.au
5. Aussie landscape (computer) programmes
Anne Windsor and Jim Wolz (JimWolz@Compuserve.com) ask.....
"We've been looking for some time for an Aussie landscaping program for our Windows95 PC. We've seen several U.S. and U.K. programs, but these typically cannot handle southern-hemisphere seasons or northerly sunshine and the plant libraries are sadly lacking in our native plants.
Can you help?"
6. Acacia mangium
There have been a couple of responses to " Acacia mangium - Wonder Plant?" mentioned in the last newsletter.
* Nanette Hooker, member of Townsville SGAP, writes
" I have found 2 reference in my book collection as follows:-
'Gardening in the Dry Tropics' by Leigh Weakley (SGAP, Townsville Branch). "Medium to small spreading tree, 15-25 m high. Occurs along water courses in open forests or along rainforest margins in coastal districts of North Queensland extending to just south of Townsville. Branchlets are acutely angled and triangular in section. Phyllodes are lanceolate-ovate to elliptical, 10-25 cm long, light to dark green with 4 conspicuous main veins. Flowers are borne in spikes 6-10 cm long, white, and moderately inconspicuous. Flowering period is Dec-June. Seed pods are long, slender, coiled or twisted and contorted. Seed is difficult to get due to several factors. Native animals include it in the diet and insect pests damage a large amount. Prefers well drained soil with supplemental watering during the dry periods. Makes an excellent shade tree."
'North Queensland Native Plants' Compiled by the Tablelands Branch of SGAP. "A small tree which occurs naturally in coastal areas around Cairns. It has enormous bright green phyllodes, especially when young, and is a very fast grower. It grows well on poor soils, and seems to have excellent potential for use in the rehabilitation of degraded land." "
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* .....and Jo Sasse sent the following detailed response as well as a Fact Sheet on the species (Jo is with the Centre for Forest Tree Technology, Heidelberg, Victoria - http://cftt.vic.gov.au) :
" I saw the query you posted about Acacia mangium, and thought I could offer a bit of background information.
This is a species which is widely established as industrial plantations in tropical areas, notably areas like Indonesia. These plantations are established primarily to satisfy the demand for industrial wood; that is, to produce logs for domestic use and foreign trade. Acacia mangium from industrial plantations is mostly used for pulp and paper production, but there are a wide range of other uses as well.
I would think that there is more information about the invasiveness of the species out there - as an acacia it has a hard and water-impermeable seedcoat which assures seed longevity, but also makes germination slow, unpredictable and difficult unless exposed to heat (usually from fire). Even then, the temperature required for germination is within a specific range (80 - 150oC). Seeds are killed by exposure to 150oC for more than 5 minutes. "
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FACT Sheet
Acacia mangium: an important multipurpose tree for the tropic lowlands
Acacia mangium Willd. is one of the major fast growing species used in plantation forestry programs throughout Asia and the Pacific. Due to its rapid growth and tolerance of very poor soils, A. mangium is playing an increasingly important role in efforts to sustain commercial supply of tree products while reducing pressure on natural forest ecosystems.
Botany
Acacia mangium is in the family Leguminosae, sub-family Mimosoideae. It has rapid early growth, and can attain a height of 30 meters and a diameter of over 60 centimeters (MacDicken and Brewbaker 1984). Inflorescences are on loose spikes up to 10 cm long with white or cream colored flowers. When in full blossom, the inflorescences resemble bottle brushes. The flower has a mild, sweet fragrance. The dark green, glabrous phyllodes can be up to 25 cm long and 10 cm broad. The seed pods are broad, linear, irregularly coiled, and up to 3-5 mm wide and 7-8 cm long. The seeds are dark brown to black, shiny, vary in shape, and range from 3-5 mm long and 2-3 mm wide. Seeds mature 6-7 months after flowering (Pinyopusarerk et al. 1993).
Acacia mangium has a chromosome number of 2n=26. Hybrids with A. auriculiformis have the potential to become an important source of planting material for plantation forestry. The hybrid seems to be more resistant to heart rot than A. mangium but tends to be more shrub-like. Moreover, the hybrid has the straight bole and stem of Acacia mangium and the self-pruning ability of A. auriculiformis (Ibrahim 1993).
Distribution and Ecology
Acacia mangium is native to Australia, Indonesia and Papua New Guinea, but now has a latitudinal range from 19o S to 24o N and a longitudinal range from 88o to 146o E. Acacia mangium is a low-elevation species associated with rain forest margins and disturbed, well-drained acid soils (pH 4.5-6.5). Altitudinal range is from sea level to about 100 meters, with an upper limit of 780 meters. It is typically found in the humid, tropical lowland climatic zone characterized by a short dry season and a mean annual rainfall between 1446 and 2970 mm. Acacia mangium can tolerate a minimum annual rainfall of 1000 mm. Mean monthly temperatures range from a low of 13-21C and a high of 25- 32o C. Though considered an evergreen species, A. mangium does not grow continuously throughout the year. Growth seems to slow or cease in response to the combination of low rainfall and cool temperatures. Dieback occurs during prolonged frost (5-6o C).
When monthly rainfall is below 100 mm, trees exhibit signs of moisture stress (Pinyopusarerk 1993). Acacia mangium tolerates a soil pH as low as 3.8, and has performed well on lateritic soils with high amounts of iron and aluminum oxides. Acacia mangium has survived on soils with as much as 73% aluminum saturation (Duguma 1995). It is intolerant of saline conditions, shade, and low temperatures. Due to dense foliage, broad phyllodes, and shallow root system, A.mangium is more susceptible to wind damage than other Acacia species.
Propagation and Silviculture
Although natural regeneration is excellent in clear-felled and burned fields, nursery propagation is the most common regeneration practice. Hot water treatment for 30 seconds promotes quick seed germination. There are 80,000-100,000 seeds per kilogram. Seed can be sown directly into nursery pots or sown in trays and transplanted to pots after germination.
Seedlings are retained in the nursery for 12 weeks or until they have attained a height of 25-40 cm. Srivastava (1993) recommends two root prunings and hardening off of the seedlings before out-planting. In low phosphorus soils in the Philippines, Acacia mangium seedlings fertilized with 30 g/tree of phosphorus showed significant increase in growth compared to seedlings that were not fertilized (Manubag et al. 1995).
Spacing of the seedlings in the plantation depends on the intended uses and soil fertility. Since natural pruning is poor, trees should be planted at close spacing. Plantations cultivated for pulpwood usually have a 4 x 4 m spacing with 830 trees per hectare. For timber production, seedlings planted at 3 x 3 m spacing provide strong lateral competition and fast diameter growth. Seedlings should be planted at wider spacing to produce heavier branches for chipwood and fuelwood (Srivastava 1993). On infertile sites, final stocking should be around 600-700 stems per hectare.
The first weeding should be two months after out-planting. Weeding of noxious plants such as climbers, creepers, and vines is recommended, but less harmful weeds can be left in the field to maintain lateral competition. The number of follow-up weedings will depend upon each site. In areas where Imperata has a stronghold, weedings should be frequent.
Pruning schedules also depend on intended use. In agroforestry systems, branches are pruned regularly to prevent competition with agricultural crops. To produce quality sawlogs, all branches below the height of 6 meters should be pruned regularly. These branches must be pruned before becoming 2 cm in diameter to avoid fungal infections (Srivastava 1993).
On degraded Imperata grasslands, Otsamo et al. (1995) observed that A. mangium had a mean annual volume increment of 10 m3/ha/year. In a 15-year rotation, pre-commercial thinning should occur at 24 months, followed by a thinning at 36 months. Per this schedule, volumes are between 290 and 439 m3/ha after ten years' growth.
Uses
Acacia mangium has a wood density ranging from 420 to 600 kg/m3 and a specific gravity of 0.65 (MacDicken and Brewbaker 1984). Due to ease of drilling and turning, it is a popular wood for furniture, agricultural implements, crates, particle board, and wood chips. Acacia mangium is also suitable for manufacturing charcoal briquettes and activated carbon. It has a calorific value of 4,800-4,900 Kcal/kg. Acacia mangium's susceptibility to heart rot limits its use for sawn timber, but it is a common pulp and paper crop in Sumatra, Sabah and Vietnam. Nontimber uses include honey production, adhesives, and as an ornamental and shade tree for roadsides or other urban forestry uses. Acacia mangium sawdust provides good-quality substrate for shiitake mushrooms.
Since A. mangium can grow on marginal soils, many farmers choose to plant this species to improve soil fertility of fallowed fields or pastures. Since trees with diameters of 7 cm are fire resistant, Acacia mangium plantations can be used as fire breaks.
Symbiosis
Highly effective Rhizobium strains have been identified for Acacia mangium (de Faria 1995). Acacia mangium has a relationship with some VAM fungi including Thelephora ramariods, Gigaspora margarita, Glomus etunicaturm, and Scutellispora calospora.
Pests and Diseases
The major pests associated with A. mangium cause damage to seedlings, branches and stems, or wilting caused by root damage. Damage does not result in death, but may deform or suppress tree growth (Hutacharern 1993).
Most disease agents of A. mangium are associated with or caused by fungi. Common disease symptoms are damping off, heart rot, powdery mildew, stem galls, dieback, leaf spots, and root rot (See 1993).
References
Duguma, B. 1995. Growth of nitrogen fixing trees on moderate to very acid soils of the humid lowlands of southern Cameroon. In Evans, D. O. and L.T. Szott eds. Nitrogen Fixing Trees For Acid Soils. Proceedings of Workshop in Turrialba, Costa Rica, July 3-8, 1994: Winrock International and CATIE. pp. 195-206.
Faria, S. M. de. 1995. Occurrence and rhizobial selection for legume trees adapted to acid soils. In Nitrogen Fixing Trees For Acid Soils. pp. 295-301. See Duguma 1995.
Hutacharern, C. 1993. Chapter 9: Insect pests. In Awang, K. and D. Taylor eds. Acacia mangium Growing and Utilization. MPTS Monograph Series No. 3. Bangkok, Thailand: Winrock International and FAO. pp. 163-203.
Ibrahim, Z. 1993. Chapter 2: Reproductive biology. In Acacia mangium Growing and Utilization. pp. 21-34. See Hutacharern 1993.
MacDicken, K. and J. L. Brewbaker. 1984. Descriptive summaries of economically important nitrogen fixing trees. NFT Res. Rpts. 2:46-54.
Manubag, J., B. Laureto, J. Nicholls, and P. Canon. 1995. Acacia mangium response to nitrogen and phosporus in the Philippines. In Acacia mangium Growing and Utilization. pp. 32-35. See Duguma 1995.
Pinyopusarerk K., S.B.Liang, and B.V. Gunn. 1993. Chapter 1: Taxonomy, distibution, biology, and uses as an exotic. In Acacia mangium Growing and Utilization. pp. 1-20. See Hutacharern 1993.
Otsamo, A., G. Adjer, T. S. Hadi, J. Kuusipalo, K. Tuomela, and R. Vuokkko. 1995. Effect of site preparation and initial fertilization on establishment and growth of four plantation trees species used in reforestation of Imperata cylindrica (L.) Beauv. dominated grasslands. For. Ecol. and Mgmt. 73:271-277.
See, L. S. 1993. Chapter 10: Diseases. In Acacia mangium Growing and Utilization. pp. 203-238. See Hutacharern 1993.
Srivastava, P.B.L. 1993. Chapter 7: Silvicultural practices. In Acacia mangium Growing and Utilization. pp. 113- 147. See Hutacharern 1993.
*********************** Written by Mary Mackey, Program Associate, Winrock International.
A publication of the Forest, Farm, & Community Tree Network (FACT Net) (formerly the Nitrogen Fixing Tree Association)
c/o Winrock International, 38 Winrock Drive, Morrilton, Arkansas 72110-9537 USA
7. A response on tree removal
Peter Vaughan has some comments on Chris Cousins' problem on tree removal.
"Ironbarks rarely drop branches or blow over. The fact that yours is, suggests there is a deeper problem, possibly with the roots. Therefore its removal is probably advised and is acceptable if replaced by other shorter natives, especially the Brachychitons.
Secondly, if your neighbour ever removes a tree that may fall on your property, never help or watch. I have been told that if you help and damage occurs to your property, the neighbour is not responsible and their insurance may not be either. If you are not there, the neighbour is responsible, even if they have your permission. "
8. Growing Australian plants in Virginia, USA
Michael Sawyer (Waterborne@aol.com) is horticulturist with The Colonial Williamsburg Foundation and is interested in propagating Australian Native Plants for a collection maintained by the De Witt - Walace Gallery of Decorative Arts in Colonial Williamsburg. When in Australia he collected some seed and have since been sent seed for propagation. He is interested in entering into a dialogue with people who might be willing to guide him through this propagation process.
Michael manages the greenhouse / propagation facility that supports the Gallery's collection.
In response, I offered to assist where I could and to also post his messages to this newsletter in case others might like to help.
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Michael's first query involved the following.....
and he goes on to ask:
"....let me first ask how long do you think these seeds remain viable? If it is not longer than three years then I should stop while I am ahead. I collected these seeds in 1995. I am hoping that most of them have remained viable being as they are from a dry climate where they may not naturally have the proper growing conditions every year for germination...
I am planning to treat the Kangaroo Paw and Banksia in about the same manner, sow them in commercially prepared seed starter mix and then cover them lightly with a thin layer of soil. I do not believe they require any pre-treatment? Would you suggest bottom heating the seed flat? The seeds are going to be grown in a greenhouse situation so I am not too concerned about time of year etc. I am already quite confused by your seasons and ours, planting by the month also means nothing to me. What I know is we are in late spring right now, going into early summer, outdoors temperatures are in the 80s sometimes going into the low 90s. How long do you suppose it will take for these to germinate? The Ginger can also be treated the same way? It is not as much a priority though as the Banksia."
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In a subsequent message, Michael posed the following questions:
"I am preparing to start some Acacia which will require pretreatment. The process is to pour boiling water over them and then let then soak overnight... Is it true that you then sow the seeds that have have settled to the bottom of the water the next day? Does this process also hold true for Templetonia retusa and Chamelaucium uncinatum? The seed packet I have also says to sow the T. retusa in a container of plant food to germinate? This sounds rather strange to me. Do they mean a solution of plant food extended in water? If so what sort of concentration are they talking about? or could they mean just some 10-10-10 right out of the bag? These are the next items on my list to address if you have experience with these species? Any word of advice would be appreciated.
What I am saving for the next round is some Jacksonia dilatata "Cladode Pea" that I collected up north."
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Anyone wishing to find out a bit more about The Colonial Williamsburg Foundation might like to look at:
http://www.fiestaval.com/colonial.htm
9. Another gremlin!
OK, OK.... there was yet another error in the March newsletter.
I suggested that readers might like to try identifying the plant photos at Michael Thompson's site.
Yes...the URL I gave was wrong. It should have been:
http://thunder.simplenet.com/wildf/awf.htm
10. Info wanted on Euc globulus
A request from Linda Graham (9601709@rmit.tce.edu.au):
"I'm studying at RMIT in Melbourne and was wondering whether anyone could mail me some information on the competitive nature of E.globulus especially when in the presence of E.sieberi and the brown and yellow stringybark's found in Victoria's East Gippsland (lowland sclerophyll areas). "
11. Help with potting mix statistics
....and another from Nicholas Bryant (50185@oac.usyd.edu.au):
"I am studying Agricultural commerce at Orange Agricultural College (Orange NSW). I am currently working on an assignment requiring the development of a marketing and business plan for a hypothetical business selling a brand of potting mix. I have surveyed the Orange area however the information I have obtained is insufficient and I am wondering if you have any basic information on the potting mix market in NSW such as number of cubic metres sold or number of bags etc.
I understand that your society may not have this information but I am hoping you may know of a contact who does. If you do I would be very grateful if you could let me know, my E-Mail Address at Orange Ag College is 50185@oac.usyd.edu.au and my phone number in Orange is 02 63629098. My postal address is 83 Spring St Orange NSW 2800."
12. Root parasites
Margaret Thompson (margaret_thompson_at_cowra@smtpgwy.agric.nsw.gov.au) has a challenge......
"I am in the process of regenerating a 4 ha area of land in the Central Tablelands of NSW. I am interested in root parasites as there are about 26 Northern sandalwoods, Santalum lanceolatum, of which 7 are very small seedlings, approximately 125 mm high growing independently.
I am also researching the possibility of regenerating the Native Cherry - Exocarpus cupressiformis. There is one quite old native cherry but there do not seem to be any more regenerating. Could you please advise me if and where I may be able to purchase seedlings."
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In a subsequent message, Margaret reported......
"Guess what I found! Three more native cherry suckers popping up within about 5-6 m from the older tree. There is a really old whitebox tree and also a younger common olive tree very close by and I was wondering if there is any way to determine the host plant, or in fact if they are using the 'mother' tree as a host. I have protected the suckers with tree guards, hoping they will survive."
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I can't offer any advice, so if you know anything about the matters raised please let Margaret (and me!) know.
13. Transplanting grass trees
A number of people have enquired about the process of transplanting mature grass trees (Xanthorrhoea species). I have no practical experience but have offered the following advice based on (hopefully) common sense. If anyone out there can offer a more practical guide, please let me know. You might also let Belinda Murray (bmurray@northnet.com.au) know as she has been the most recent enquirer:
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Transplanting Grass Trees
"As far as I am aware most of the Grass Trees (Xanthorrhoea species) that can be bought in nurseries are transplanted by mechanical means. You can do it manually but there is more chance for things to go wrong, particularly if the plant is large.
If the plant is growing in sandy soil, the problem is more difficult. It needs to be in a soil that is not going to fall apart easily.
This is the approach I would take:
14. Dates for your diary
Keep these in mind if you're in the vicinity .
Illawarra Grevillea Park - Open days (10am to 4pm)
The park features a wide range of Australian plants with the emphasis on grevilleas. Barbecue and picnic facilities are available. Admission is $2 for adults; children free. The park is located at the rear of the Bulli Showground, Pacific Highway, Bulli. Further information from the Park's web site: http://www-personal.usyd.edu.au/~markz/grevillea/
August - Saturday 29 to Sunday 30, 9am to 4pm Shortland Wetland Centre, Sandgate Rd, Shortland, NSW. This event will be hosted by the Newcastle Group of the Australian Plants Society and there will be local garden displays, cut flowers, plant sales, environment and conservation group displays, craft, garden walks and "kids' korner".
September - Saturday 5 to Sunday 6 Well known speakers, garden visits, walks. To be held at the Pastoral and Veterinary Institute, Mt Napier Rd, Hamilton, Victoria. Contact Cheerree Densley (cherree@standard.net.au).
September - Thursday 10 to Sunday 13 Kariong, New South Wales (5km south-west of Gosford on the Pacific Highway) The Central Coast Group of the Australian Plants Society will a major part of this annual Festival featuring over 100 non-profit and commercial exhibits. There will be sales of heath, rainforest and grafted plants (Grevillea, Hakea, Eremophila, Prostanthera), native plant displays, growing and propagation advice and plant propagation demos.
September - Saturday 12 to Sunday 13 Mt Gravatt Showgrounds, Logan Rd, Mt Gravatt, Queensland Featuring displays of Australian plants, Study Group displays, propagation display, plant, cut flower and book sales.
September - Saturday 19 to Sunday 20 Darley Park, Bacchus Marsh, Victoria 1000s of plants for sale including grafted species, ferns, rare and the unusual. Entry $2, children free. Walk through Darley Native Gardens and view many rare and unusual grevilleas, eremophilas, darwinias, etc.
April 1999 - 14 to 18 This will draw together growers, exporters, wholesalers, florists, researchers, extension officers, educators, and students working on Australian and South African native cut flowers. The Conference will be held during the Melbourne International Flower and Garden Show. Further details from the web site: http://www.nre.vic.gov.au/agvic/ihd/resource/wflow-1.htm
July 1999 - 10 to 16 Programme and Registration details when they become available
Finally.......
An advertisement.....sort of.
Australian plants online, this newsletter and the main web site is sponsored by the Association of Societies for Growing Australian Plants. Terrible name, I know....just call it ASGAP!
If you're interested in growing, propagating, conserving or just learning about Australian plants, maybe you might consider joining one of the Regional groups. or subscribing to the Society's colour journal "Australian Plants".
There's no obligation, of course, but if you want to find out more, take a look at:
http://www.silo.riv.com.au/SGAP/sgap.html
Best wishes Brian
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