Re: Proteaceous Plants
- To: m*@ucdavis.edu
- Subject: Re: Proteaceous Plants
- From: J* A*
- Date: Fri, 9 Jun 2000 09:14:07 +1000 (EST)
At 07:45 7/06/00 -1000, Mach wrote:
>Actually, I will have to disagree on several points. The silky oak grows
>just fine up in Kula to the point that it is a weed. Right now and as it
>has been allmost every year we are under a drought watch.
I suspect your definition of a "drought" in Hawaii is not the same as ours,
if you can fit one in every year. :-)
>These trees grow
>huge and will take over pasture, etc here in Upcountry Maui.
Yes, silky oaks are tough, and once they get going can easily take a couple
of months without rain. They are often used as a street tree here, even
away from the coast. They are also standardly used as rootstock for
grafting on the more fussy Grevilleas and related genera, since they'll grow
in just about anything, anywhere. (Both the silky oaks in my garden are
from grafts I bought of rare grevilleas where the top part died after
struggling on for a year or two.) But their native habitat is sub-tropical
rainforest.
> Second point
>my in laws don't have a constant irrigation system so most of the fields
>are dependant on the rains for water yet all the Proteas, Leucodendrons,
>and Banksias are doing OK. I will submitt that they are drought tolerant
>(perhaps not evolved for true dry season conditions).
I think you're agreeing with me here. Leucadendrons, Banksias, and Proteas
are, as I said in my first post, mostly from areas like Western Australia,
which have a pronounced dry season and annual rainfall in the 10-20 inch
range. The east coast Banksias generally grow in very poor sandy soil.
> Third most of the
>research regarding over fertilization of proteaceous plants in Hawaii has
>come from work on Macadamias. I suspect that our odd soils make for some
>intresting problems with phosphrus as much of it gets tied up via the iron
>and alluminum oxides.
Yes, you're the experts on Macadamias. I do have one, which I fertilize
whenever I happen to think of it. But my comment re phosphorous was based
more on the advice you see in all the books that rainforest protaceae in
general don't suffer from problems with phosphorous like their dry-land and
poor-soil cousins, since they don't depend on protaceous roots, and respond
well to fertilizing just like other "ordinary" rainforest plants. But maybe
your soils do make a difference.
John.
