This is a public-interest archive. Personal data is pseudonymized and retained under GDPR Article 89.

RE: Acacias (was "Mimosa")

>From the Sean's description  of a flat-topped 'savanna' look
it really isn't the species so much as the constant grazing pressure
exerted by the many large herbivores that keep the trees that way.  The
species most favoured by zoos for this type of planting
AND most worrying to people in my position is Acacia karoo

A. karroo was planted in a savanna seting in eastern Australia and it
took a lot of time and great expense to remove them once they realised
how much of a problem they were going to be.
We have a large number a very weedy invasive Acacias in Australia but
few match the potential shown by the african tree species.  Our Acacias
have gone rampant in South Africa and they rue the day they brought them
across, although to be honest they may not have intentionally imported
all of them.
There are other weedy Acacias we keep an eye out for one being A.
nilotica with nine varietys from three different climatic areas spread
from Central Africa to India. 

For all that there are so many species of Acacia (some 1200 spp.) with
possibly three sub genera and 700 spp. native to Australia there really
is something for everyone in this group.
I have a friend in the hills at the back of Perth who has an Acacia
garden. You can't see his house for all the shrubs and small trees out
the front and when they start flowering its just a golden haze the whole
70 odd metres up to his house.  He prefers the prickly ones also as they
tend to put off the local cats from preying on the native birds that
come to feed on the nectar.  

Cheers, Rod
Rod Randall
Weed Risk Assessment
Weed Science Group, Agriculture Western Australia
Home Page  http://www.agric.wa.gov.au/progserv/plants/weeds/Weedsci.htm

             "I weed..."


> >Subject: "Mimosa"
> >
> > 	A woman I know recently returned from holiday in the South of
> > France, Montpelier and thereabouts, and she was enraptured by the
> > "mimosa" trees growing there. She said they grow practically like
> > weeds, and I think have yellow flowers. I told her I would ask on
> > this list; does anyone know what they are?  Then I guess the next
> > question will be: Wonder if they'd  be hardy here, on Southeastern
> > Vancouver Island, which is "cool Mediterranean".
> > 	Thanks,      Nancy Jakusz  (B.C. -- Canada)
> >
> 
> Nancy -
> 
> This would almost assuredly be Acacia decurrens or A. decurrens
> dealbata.  We also have this weedy species here in California, and
> which it can be strikingly beautiful in full flower, it does spread
> at the roots, from which it can regenerate quickly after a fire, or
> intentional removal (or being killed by severe frosts).  Sunset
> lists this species as hardy to its western garden zones 8&9 (you are
> most likely somewhere in their zone 5).  I find no other Acacia
> rated for Vancouver Island.  Albizzas (pink flowers) are somewhat
> similar, and should be hardy for your area.
> 
> Others -
> 
> On the topic of Acacias, I've been trying to help a friend find some
> species with the distinctive flat-topped 'savanna' look for a
> planting he is doing for a local zoo.  Does anyone have information
> on any of the following species, or any other exhibiting this
> distinctive growth pattern?:
> 
> Acacia erioloba - Camel Thorn
>  A.    tortilis heteracantha - Umbrella Thorn
>  A.    xanthophloea - Fever Tree
>  A.    sieberiana woodii - Paperbark Thorn
> 
> This last species is perhaps the most striking - if anyone knows of
> seed availability, I'd be most interested.  It is native to woodland
> and grasslands from Natal, Zululand, Swaziland to Transvaal,
> Zimbabwe, Botswana and Namibia.  It has an attractive corky, yellow
> green stem with peeling bark, feathery light green foliage and
> flowers heavily with creamy white to pale yellowish balls.
> 
>  Sean A. O'Hara                     sean.ohara@ucop.edu
>  710 Jean Street                    (510) 987-0577
>  Oakland, California 94610-1459     h o r t u l u s   a p t u s
>  U.S.A.                             'a garden suited to its purpose'
>
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index