Wednesday, October 28, 2015

Australia 1. Around Perth

The Western Australia Botanic Garden in Kings Park, Perth, is a marvelous
place to begin learning about the local flora.
After my 1998 visit to South Africa, I continued eastward across the Indian Ocean to Australia to catch part of the spring wildflower season there.  Australia is another botanical paradise, filled with wondrous and strange plants.  This island continent has been isolated from the rest of the world's land masses so long that its flora is quite unique.  Many of the plant families are recognizable, but with genera and species unlike what we know in the northern hemisphere.

Chamaeleucium is a shrub in the family Myrtaceae,
which also includes Eucalyptus, Melaleuca and the
bottle brushes.
Members of the myrtle family (Myrtaceae), for example, arrived early, when few other flowering plants were present, and radiated dramatically into many genera and hundreds of species.  There are over 700 species of Eucalyptus for example, which dominate most of Australia's forests.  Other genera in the Australian Myrtaceae include the popular ornamental bottle-brush (Callistemon) and the genus Melaleuca, a species of which is a noxious invasive weed in southern Florida.

The unique southern hemisphere family, Proteaceae, which is so spectacular in South Africa, is in Australia also, with marvelous genera like Banksia and Grevillea.  The legume family (Fabaceae) has proliferated here, providing nitrogn to the mineral-poor soils.  Australia, particularly western Australia, is also home to the greatest diversity of sundews (genus Drosera) to be found anywhere. These carnivorous plants also bring nitrogen into the food chain.  And then there are the ground orchids, which in North America are rare and often endangered.  In Australia, one sees them nearly everywhere.

Xanthorrhoea australis resembles the Yuccas of
North America, but is unrelated to them.

There are some unique families here as well - the Xanthorrheaceae, with growth forms that resemble our yuccas, and the endemic pitcher plant, Cephalotus, which is in a family of its own.

I arrived at the city of Perth, capital of the state of Western Australia.  As in the rest of Australia, the human population is concentrated in a few cities and towns, mostly near the coast, leaving the huge interior very sparsely inhabited.  Much of that interior is desert, but the coastal areas and the mountains have ample rain, mostly in the winter.  This supports varied vegetation similar to what we would find in California or the Mediterranean region.  There are Eucalyptus forests as well as areas dominated by evergreen shrubs.

In a display of spring wildflowers at the Kings Park Gardens
in Perth, members of the family Proteaceae are featured.
In Perth, I began with the botanical garden, a great place to get an introduction to the local flora.  As
in South Africa, there are many people who take great interest and when I arrived in October, there was a wildflower show going on at the Garden, as well as planted displays of the local flora.

Banksia blechnifolia has an underground stem system and strongly resembles
some cycads, like Florida's Zamia floridana.

From Perth, I struck out toward the southwestern corner of the country, staying in the town of Albany.  From there I explored the countryside, including the fascinating D'Entrecasteaux National Park.  That will be the subject of my next couple of postings.

Some species of Australian sundews
(genus Drosera) take on the form of  upright,
 leafy shoots. Some are even branched in a shrub-like
configuration, or climb like vines.

Kangaroo paws, Anigozanthos manglesii, spring to life soon
after a fire in the woods near Perth.  
Fires are natural in Western Australia, as they are in 
California and other Mediterranean climates. 
Frequent fires clear debris and weedy growth, 
preventing more catastrophic fires. 

Anigosanthos flavidus has brilliant orange flowers.

Darwinia meeboldii is a striking member
of the Myrtaceae endemic to Australia.

Caladenia flava is a striking ground orchid, one of
hundreds in Australia/

The brightly colored flowers of Eucalyptus consist mostly of

Kingia australis, or grass tree, is another member of
the Xanthorrhoeaceae.

Boronia megastigma (Rutaceae) has cheery, bell-like
Banksia hookeriana sports a massive head of tiny flowers.

Hovea elliptica is a member of the legume
family.  Its roots harbor nitrogen-fixing
Diuris brumalis is another spectacular ground orchid.

Xanthosia rotundifolia is a member of the Apiaceae,
with dove-like clusters of bracts below each umbel of flowers.

Banksia praemorsa is another spectacular member of the Proteaceae. 
Its head is made up of hundreds of tiny yellow flowers.

Banksia ashbyi brightens the bush with
brilliant yellow flower heads.

Eremophila maculata is a shrub in the
Chorizema ilicifolium is another of the many
species of legumes in Australia.
Dillwynia laxiflora flowers have the same
color pattern as the Chorizema, though it is
only distantly related.  It suggests that the
two species share the same set of pollinators.

This fuzzy-leaved Solanum is a relative of the tomato and the potato.