Greetings fellow Foxies,
                                     Recently I climbed Yilliminning rock in the evening which is a great time to gain an understanding of its formation. There is a great story in the rock itself if you look closely.
Most continents in the world consist mainly of granite (a light coloured quartz and feldspar rich rock that crystallised out from molten magma (igneous rock). The continents are separated by black dense crystalline rock (a bit like dolerite used for road building) that underlies ocean floors.
 I suspect that the granite here formed up to two thousand million years ago (your ancestral line may have been bacteria then) when two geological plates were colliding. As one slowly slid underneath the other it was forced into deep molten rock of the mantle and gradually melted.
Being lighter, large domes of molten granite gradually forced their way upwards. They moved upwards through solid rock by “cauldron subsidence”. Intense heat from dome magma causes rock above to fracture and fall into the magma, creating a chamber that the magma moves into. Fractured rock from top and sides is often incorporated into the dome as partially melted xenoliths.
If they reach the surface, volcanoes spew out a fine grained granite like rock called andesite. However most times the domes stop two kilometers (km) or more below the land surface and gradually solidify into granite. You can tell that it cooled slowly because granite has large evenly spaced crystals.
 
Just think about it. As you stand on the top of Yilliminning Rock, you are 2 km below an ancient land surface.
 
The diagram on left shows ocean crust melting in the hot mantle after it has collided with and been forced underneath a continent. Molten material separates into dense black gabbro and lighter granite that rises towards the surface of the continent by cauldron subsidence.

​Like most of the large granite outcrops in the wheatbelt, Yilliminning Rock is an inselberg (steep sided dome of bedrock that has been exposed above the surface as surrounding land eroded away).
If you wander over the surface you can see the relatively uniform speckled pale crystalline granite.
But look carefully, and you will see more.
Yilliminning rock contains lots of roughly north-west/south-east corrugations that are easily seen at dusk as shadows define them. Simplistically, I think that these could be due to slight differences in rock composition from

• Magma intruding cracks in the cooling rock.
• Changes in crystal size and possibly mineral composition that occurred due to temperature and pressure changes as the granite slowly cooled while still molten.

The huge sheets of rock are geologically a very recent, and form in a process called exfoliation. Basically, granite is a very poor conductor of heat, and hot-cold temperature variations cause onion skin type cracks.
In winter, cracks expands as water in them freezes. Voila, a great home for Ornate Dragon Lizards (Ctenophorus ornatus). Eventually gravity and vibration/ pressure from earth movements (or more commonly humans) causes these sheets to break off and move downslope (or be crushed or carted away by humans!)
 The image below shows granite structure in a broken sheet

​Images below show rock sheet on the northern side of the rock. If you sit quietly, the dragon lizards (mini dragons really!) will come out. Watch them bobbing up and down to warn off intruders and running around on their tippy toes (evolved to help them avoid heat from hot rocks

Here are some great references
Geology of Granite
Overview of Granite Outcrops in Western Australia

Greetings fellow Foxies,
The town named Wolwolling came into existence with the construction of the Great Southern Railway in 1889 and renamed as Highbury in 1906. The town has a hotel/motel, a general store and a public toilet for visitors.
The townsite is on a rise adjoining the Arthur River flats that is underlain by east-west and south-east/north west trending granite and dolerite rock. Landscape trends can be seen on the map below with a dolerite dyke forming the gravelly mesa in the west and underlying gravelly duplex red morrel forest and strips of salmon gum in the gently undulating eastern reserve.
There are few rock outcrops in what is prime agricultural land with outstanding wildflowers. West of the Great Southern Highway most remnant bush has been extensively modified, but the eastern reserve is in remarkably good condition. I have identified two wonderful wildflower areas (1 and 2) and two others that more suited to committed enthusiasts (3 and 4).
A printed guide will be available at the Dryandra Country Visitor Centre next season.

 Stop 1 has a wildflower walk (about 1km grade 2 easy walk) that has a large array of orchids and other wildflowers in the water-gaining sheoak woodland. Good from May to November, but the best time is September when there is usually a carpet of Stark White Spider Orchids in the open wandoo flat on the northern side. From Great Southern Highway turn onto Highbury East Road then park in red morrels on the Jenkins Road corner. Cover up and use insect repellent as the mosquitos can be ferocious. This is a great birdwatching area and echidnas are active.

Stop 2 is a lovely patch of sandy surfaced open kwongan scrub immediately to the right (west) as you arrive from Narrogin.  You can turn park in the firebreak. A highlight here is the Caladenia longicauda/ Caladenia falcata hybrid and stark white spider orchids, and a range of everlastings and flowering shrubs.

Take the southern access across the railway line and park under red morrels to visit stop 3. A short walk through open bush intersects with an old track that passes through an unusual little saucer-like gravelly upland patch that is bounded on all four sides by slightly uplifted geological faults or dykes. Low prickly Allocasuarina microstachya tammas are interspersed by an unusual range of interesting shrubs and annuals.

To reach stop 4, turn west on to Campbell St from Great Southern Highway, drive up the hill past the tavern and park at the gates of the closed entrance on the curve. There is a track on the opposite side of the road with a Eucalyptus incrassata mallee gravelly rise that changes to a dense broombush (Melaleuca hamata) mini-breakaway slope. Nice show in November.
The slideshow below is just a taste of these lovely spots.

Greetings fellow Foxies,
Candy Block is a little known outlier of Dryandra Woodland on the Narrogin-Wandering Road near the turnoff to Cuballing. It is a great place to visit in the growing season to see some great flowers and interesting scenery. The whole area is underlain by really ancient (2.8 billion years!) granitic rocks that determine the pattern of ridges, waterways and present day soils. Compare this with much of the northern hemisphere that has lots of sedimentary rocks and was scoured by glaciers only 10,000 years ago.
Candy Block has more dramatic slopes and breakaways and gullies and more variable soils than the main block, that reflect variations in the underlying rock. In particular more resistant laterites on NW-SE dolerite dykes have remained while surrounding soils eroded to form dramatic mesas with steep gullies that makes for a great walking trail.
Thicker red lines show good driving tracks to enjoy the reserve. Please enter by the northern entrance as cars may slide and collide with oncoming vehicles while getting a run-up to tackle a blind steep loose gravel  ascent on the southern entrance.
Note that the narrow red lines are fire access tracks that may be rough, boggy or blocked by fallen trees.

The 1.5km Kwongan Trail is an easy walk through a yellow sand wildflower hotspot and other bush that includes attractive marri/ wandoo woodland and a powderbark/ wandoo spot containing Frog Greenhood, Beard, and Blue Sun orchids in mid/late October..

The yellow sand patch is a kwongan wildflower hotspot that reaches its peak in September to November.
The slideshow below gives a snapshot of this remarkable reserve.
Click here for blog on the lovely stages of development of Petrophile circinata and Isopogon villosa
Spring orchids are less common. Cowslip orchids are widespread, greenhood, jug, snail greenhood, donkey, blue china and fringed mantis orchids occur in places in sheoak woodland.
 
Sections of Candy Block are baited monthly to control foxes and feral cats. If you discover a “sausage” style bait on the ground please do not touch, remove or disturb it. Pets are not permitted and all pets are likely to be highly susceptible if taking a bait.

Greetings fellow Foxies,

I found these plants on an unusual patch of yellow sand in Dryandra Woodland Candy Block that has Drummond’s Mallee and a large number of shrubs. In August I noted a low compact plant with lovely foliage that I called “carrot plant” while waiting for it to flower. Flowers in late October revealed it to be an uncommon species, Petrophile circinata. Circinate means curled around itself, presumably referring to the whorled leaf arrangement. Images below show the plant and flower.
As this species was coming into flower I noticed that there were a few very similar plants that had beautiful hairy red growth appearing on what I thought were dead flower stalks.
Gadzooks! The local experts were confounded until the growth expanded into the flower of slightly later flowering Isopogon villosus (villous means hairy with long soft hairs). The flowers emerge from thickened scaly clumps of old growth.
To my uneducated eye, vegetative growth of both species is similar, but Petrophile circinata leaves are a slightly darker green and leaf petioles have a distinctive linear fold in the petiole stem.
I usually have no problem distinguishing Isopogons (smooth fruiting nut) from Petrophiles (scaly nut), but these squat species are a real challenge. After a fair bit of excavation in the prickly growth I eventually found a rather confusing nut on the stem below the flowering clump.
The slideshow below follows both species as they flower.