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Help with Seed

• "Propagating Australian Plants" by Alec Blombery and Betty Maloney (Kangaroo Press)

• "Germination of Local Native Plant Seed" and "Seed Collection of Australian Native Plants" both by Murray Ralph (Imprenta)

Another is "From Seeds to Leaves", I think by the Forestry Commission but I'm not sure.

David Lightfoot
Australia

Thanks, David. Another good little booklet is "How to Germinate Native Tree and Shrub Seed Enjoyably" which was published by Greening Australia some years ago. It's great and the price is right (free!). I'm just not sure if it's still available.

For those really keen, the plant propagation "bible" is "Plant Propagation; Principles and Practice" by H.T.Hartmann and D.E.Kester, which has recently been released in a new edition.

Murphy Strikes Back!

Avril Tolley
Hercules, California

Not being a tomato grower of any note, this is an experience I've missed! I do, however, routinely run into (literally) webs erected by St Andrew's Cross spiders across the narrow walkways around the house. I keep telling myself the 8-legged occupant is harmless, but it's a difficult proposition to accept when I'm sure I can feel it crawling down the back of my neck!

Thanks for sharing your arachnid experiences.

And again.......

1. The Sprinkler Law. All sprinkler systems are specifically designed so that, when adjusting a sprinkler head its neighbour hits you in the back.
2. The Law of Self Destruction.The amount of attraction exercised on walls and trees and the rising tendency of buried cables, pipes and drains towards any digging instrument, is in exact proportion to the machine's destructive capability. Pop-up sprinkler-heads are strongly attracted to mowers passing overhead.

Eric Rowe,
via CompuServe

I suspect they'll never be completed....the human species will only reach the peak of evolution when gardeners have investigated every possible way to make complete geese of themselves.

So much to go wrong, so little time.

Rare Plant in Danger

Persoonia nutans . Select the thumbnail image or plant name for a higher resolution image (23k).

The Federal Government's proposal to consider Holsworthy as a site for Sydney's Second International Airport will endanger this significant population. If you wish as an organisation to register your opposition to this proposal, do so to the Environment Protection Authority as soon as you possibly can.

Greg Lambert,
Australia

I referred this information on to the local SGAP Group but thought that concerned individuals might like to know about this matter and make a submission if they think it warranted.

Threat to Revegetation Projects

TREAT is appealing for help. Enquiries (all STD 070) Joan Wright 913474, Tony Irvine 912096, Col and Barb Walsh 965879, Doug Burchill 953644, Elinor Scrambler 953296.

An example of TREAT's work is the wildlife corridor between Lake Barrine and Gadgarra State Forest - thousands of hours of community work, trees and landowner's generous co-operation will be wasted if the nursery has to close. Is there a story here? Can you tell Australia about this tragedy in the making?

Kevin Finch,
Queensland

Well...there's certainly a story, an all-to-familiar one, I'm afraid. I hope that anyone, especially Queenslanders, who deplores this short sighted action will get in touch with one of the TREAT representatives. Without knowing the full story, it's difficult to contemplate a more cost effective project, given the amount of voluntary time donated by concerned locals.

Italian Banksias

Can Banksia integrifolia grow successfully on this kind of land? Which is the suitable distance between the plants?

Can drip irrigation be used?

Luca De Vincenzi,
Italy

Banksia integrifolia and B.marginata are two species which can be grown on alkaline soils. B.media has also been reported as successful. Whether other species would grow is difficult to say as most species grow naturally in acid soils.

B.integrifolia can grow to 20 metres high but is more commonly seen around 8-10 metres with a width of 5-6 metres. You can plant them as close together as you like, depending on the effect you want. Probably 3 metres would be about right for a screen.

Drip irrigation would be quite suitable for these species.

Good luck with your Banksia growing...let us know how you progress.

Banksia media . Select the thumbnail image or plant name for a higher resolution image (34k).

Missing Seeds

Ainsley Martin,
via CompuServe

If everything goes according to plan, all Banksias have two seeds per follicle, separated by a woody separator. It's not uncommon, however, for one seed to abort perhaps due to environmental conditions such as lack of rainfall at appropriate times.

An Alternative Lawn?

Gurf Yeo,
New South Wales

The plant is Dichrondra repens and it's often suggested as a suitable lawn replacement. I've never seen it used for that purpose, though. It's not "grass-like" in appearance - it's a prostrate, spreading plant with kidney-shaped leaves about 25-35mm in diameter. It's known as "Kidney Weed" for this reason.

To quote Elliot and Jones "Encyclopaedia of Australian Plants"...."Forms a dense mat of leaves and is sometimes used as an alternative to grass lawns, although it does not withstand constant foot traffic.....It can be a problem to eradicate once established amongst other plants"

It's very widespread....you may have it growing locally without realising it.

As to getting hold of it...to be honest, I don't know. I can't imagine that nurseries would stock it given its "weedy" status and, although it can be grown from seed, none of the seed catalogues I have list it. If you can locate some, you should be able to transplant it easily.

Eucalypts - Vegetatively

Eucalypt Domestication and Breeding

KG Eldridge, J Davidson, CE Harwood and G van Wyk

CSIRO Division of Forestry/Eucalyptus and Forestry Services, Armidale, NSW/CSIRO Division of Forestry/CSIR, Division of Forest Science and Technology, Pretoria, South Africa.

Eucalypts are being brought into cultivation as wood-producing crops throughout the warmer parts of the world. Eucalypt Domestication and Breeding explains how to get better seed for these expanding plantations. Contents include: Eucalypts natural and planted; Genetic resources of eucalypts; Matching species and provenances to site; Testing species and provenances; Breeding strategies and breeding plans; Reproductive biology of eucalypts; Selection and breeding; Seed production; Mass vegetative propagation; and Looking ahead

1993, 288p., refs, illus., hardcover ISBN 0 19 854149 X
Publisher New York: Oxford University Press

Do you know this publication?

Is there more information available on experiments with vegetative propagation?

Are there research stations or researchers who I can contact?

It would probably be a good idea to collect amateur results. Can any of your readers report positive results on eucalypt propagation from cuttings? I'm very interested in information on techniques used.

Jos Kevenaar,
The Netherlands,
E-mail: jkevfast@epsilon.nl

No, I don't know the publication and, as far as I am aware, the only successful propagation of eucalypts from cuttings have been been achieved using juvenile foliage.

If any reader can assist Jos, please contact him directly (but also drop me a line too - I'm sure many readers would be interested in this topic).

Stocking Up On Callistemons

How does one best develop suitable stock plants for propagation?

What is the treatment required for these stock plants to best produce material for propagation?

What special facilities are required, if any, for the propagation of callistemons?

Callistemon phoeniceus, "Pink Form". Select the thumbnail image or plant name for a higher resolution image (30k).

My Email address is prospero@h141.aone.net.au

Bronwyn Herbert,
Australia

I think that the development of healthy stock plants is an issue best addressed by a nurseryperson. If anyone can assist Bronwyn, please contact her directly. You might also consider getting in touch with the people at the Australian National Botanic Gardens (http://osprey.anbg.gov.au:80/anbg/anbg.htm). They do a lot of propagation and might be able to help.

Callistemons are generally fairly easy to propagate by either seed or cuttings. For cuttings, some plastic structure to maintain humidity is fairly important. The methods used by SGAP members are outlined briefly on the Society's Propagation Pages.

Acidic/Alkaline Soils and Grevillea

I am a volunteer worker with the University of Arizona, Cooperative Extension, Tucson, Arizona. I have developed a computer data base with 22 fields on Arid Lands Plants. The data base has been utilised by the University to develop and publish - last September - a CD ROM on the subject matter, called "Desert Landscaping". I am in the process of reviewing our information on Australian native plants, primarily those from the semi-arid lands of WA and NSW; I'll be glad to provide more information on my work upon hearing from you.

Besides the acidic soil statement, is the feature of invasive roots, and no need of fertilisers common to all Grevillea? Our soil in the USA South West is low in organic material, rich in mineral elements, high pH (alkalinity). Moderate rains do come in the summer, never exceeding 7 inches (180mm) for July-September, yearly average 12 inches (300mm).

Ed Stather,
Arizona, USA

I don't think there's a definitive answer to this. There are over 300 species of Grevillea and many have simply not been cultivated widely enough to fully understand their cultivation requirements and tolerances. The best I can do is quote from the recent "Grevillea Book" (Vol.1) by P.Olde and N.Marriott:

"Nearly all Grevillea species occur naturally in acidic to neutral pH soils and are usually quite intolerant of alkaline soils (pH > 7.0), turning yellow (chlorotic) and slowly dying. Those species that occur naturally in alkaline soils, however, generally perform just as well in acid soils......Plants in slightly alkaline soils can often be cured of iron chlorosis by drenching the soil or the foliage with chealated iron."

The same publication has an extensive checklist of all Grevillea species and indicates those which are tolerant of alkaline conditions (approx 100). It doesn't indicate which species occur naturally in those soils.

I think the article you are referring to is the one describing the "invasive" tendency of a few Grevillea species in Quenbeyan, New South Wales. The article wasn't meant to indicate that Grevilleas have invasive roots...just that those particular plants had started to invade native bushland by seeding freely. Generally I would say that Grevilleas have a root system no more invasive than any other plants of a similar size.

Grevilleas, like all plants, need a balanced nutrient regime but, because they have proteoid roots, they can be very sensitive to excessive fertilisation, particularly to fertilisers high in phosphorus. By all means, apply fertiliser but we would recommend a slow release type with a below average fraction of phosphorus.

Rotting Roots?

Is it going to spread to the rest of my garden? Is it going to affect my banksias and melaleucas? Can I companion-plant anything to repel it? Any ideas would be welcome.

Phil Bates,
Newcastle, Australia

This is a fairly specialised topic and a comment from a soil scientist would be most welcome.....

My knowledge of Phytophthora is fairly general and I suppose it could affect a Grevillea robusta but, as that particular species is pretty tough, I wonder if something else could be the cause. Perhaps physical root damage combined with stress from dryness? As far as I'm aware, Phytophthora is not uncommon in east coast gardens so I wouldn't be too concerned about the spread to other parts of the garden. There's probably not a lot you can do about it anyway. If it is Phytophthora, the banksias may be at risk but, if they're eastern species, they will probably be OK. I'd be less worried about melaleucas, many of which occur naturally in poorly drained locations and seem more tolerant.

Companion planting?? I seem to recall reading or hearing something recently on this but I can't locate the reference. Can anyone help?

Australian Plants for the Los Angeles Area

Robert Tanowitz,
Los Angeles, USA
Email: robnan@earthlink.net

From what I understand, your climate is Mediterranean-type with dry summers. If this is the case many of the plants from southern Australia, particularly South Australia and south Western Australia should do quite well. A lot of these plants perform poorly in areas with wet, humid summers.

A good source of information for you would be Jo O'Connell who operates the Australian Native Plants Nursery at 9040 North Ventura Ave, Casitas Springs, CA 93001 (phone 805 649-3362). I know Jo personally (she used to be my next door neighbour here) and I'm sure she will help if she can. She also did a lot of the development and planting at the International Centre for Earth Concerns, Ojai.

Another possible contact is the Australian Plant Society of California. The last contact I had was Kathy Musial, PO Box 50722, PASADENA, California, 91115.

Perhaps any Californian readers growing Australian plants can assist Robert.

From Singapore to Victoria

My first question is regarding grasses or reeds suitable for growing around a dam. We are planning to join two small dams together and enlarge them having a small copse of existing eucalypts as the basis of an island ( about 2-3m square) in the middle. There are quite a few frogs around the existing dams and I want to encourage them plus any other wildlife. Could you suggest anything to plant on the banks please?

My second question is about identifying eucalypts. I have a good book with photos of the trees and their inflorescences, but no photos of leaves. I can't identify trees easily and there's one that particularly annoys me - it has ovoid leaves, even as an adult, which are very bluey-teal coloured. My book is great on description but I really wish it had photos of the leaves too. Can you recommend one?

My third question is that I have plenty of "gum-nuts" from the Victorian "Eurabbie" tree which does grow wild in this little section of the Pyrenees. How can I get the seeds from these off to the best start i.e. when, where and how should I plant them?

Melissa Aldenhoven,
Singapore

I did a quick pass of the first question to John Wrigley, the well known author, who is far more expert on these matters than I. John's advice is:

"There are many options. Frogs and tadpoles appreciate shelter from the many other predators that will occur in your dam. Fish, dragon fly larva, birds all enjoy a meal and some will even eat the frogs' eggs. So some plants will need to be planted in the water as well as on the banks.

The following is a list of plants in the various categories of water depth and moisture requirements.

For depths of 20 cm and more: Vallisneria, Potamogeton (any species), Myriophyllum papillosum, Ottelia ovalifolium.

For shallower water: Bolboschoenus (any species), Eleocharis (any species), Schoenoplectus, Triglochin procera, Juncus (any species), Isolepis (any species).

For the banks where soil is wet: Baumea (any species), Juncus (any species), Phylidrum lanuginosum, Villarsia (any southern species), Carex appressa, C. gaudichaudiana, Alisma plantago-aquatica.

I would avoid Phragmites and Typha spp. as they are very invasive.

These plants are available in Victoria by mail order from Dragonfly Aquatics, RMB AB 366, Colac, Vic., 3250"

As for the third question, have you had a look at the Propagation Pages at the SGAP web site? The general notes there should help as eucalypts are not usually difficult to germinate. (using my "Brooker and Kleinig, I find that "Eurabbie" is Eucalyptus bicostata!). The best time to plant would probably be spring but they can really be started at any time as long as the young seedlings can be protected from drying out in summer and from the cold in winter.

Australian Plants online - December 1996
The Society for Growing Australian Plants