About 5kms south of the centre of Pingelly on the Great Southern Highway, this 93 hectare reserve is a historic spot with lovely wildflowers. It was originally selected for gravel as ballast for the adjoining railway some time before 1900, then became a gravel pit for Pingelly shire in later decades. The northern side of the reserve is prime agricultural land and great wildflower country, which was saved from the plough by the gravel pits.
There are many bush tracks and an unofficial trail bike circuit. Apart from a high gravelly ridge to the south and a dolerite spur to the north, the land is gently sloping granitic sand or gravel over clay with a number of small waterways. Many of these tracks are only fit for 4-wheel drive vehicles due to boggy spots at waterway crossings.

Northern Side of Station Road
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The landscape changes from gently sloping open Wandoo woodland to the east which gradually rises to a Wandoo, York Gum and Rock Sheoak dolerite loam spur. It is excellent walking and wildflower country. Amongst the orchids I saw lots of Stark White Caladenia longicauda subsp. eminems and Green Spider Caladenia falcata orchids, a hybrid of the two, and an unusual Green Spider Orchid variant. I found some threatened Anigozanthus bicolor, and suspect that there are other interesting species to find on the winter-wet flat.

Southern Side of Station Road
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The reserve was designated for collection of gravel for railway line ballast before 1900, and this side is extensively disturbed. Most of the gravelly ridge has been mined for gravel, and gently sloping land to the north is a patchwork of tracks, clearings, soil heaps, and very weedy patches interpersed between almost pristine bush. Unfortunately some locals have also dumped rubbish here.

According to Peter Narducci, ​The ballast pit in Station Road was used to supply screened gravel for the Great Southern Railway. A spur rail line crossed the highway to the ballast pit from the Pingelly end and another spur line crossed the highway from the ballast pit towards the Popanyinning end. A railway station was constructed near to Station Road. The name Station Road has remained. In later years, the Shire of Pingelly excavated many metres of gravel from the ballast pit and was used to construct many of Pingelly's town streets.
Despite much searching of the area and adjoining railway line I could find no sign of railway station or lines. A spot shown on Google Maps labelled "Old Ballast Pit' coincides with a linear weedy area in a well defined waterway, and there is a similar linear weedy spot in an adjoining waterway to the north (see green areas on the map). I am intrigued about the locations as these areas would be waterlogged in winter, and certainly not suitable for train lines. Gravel dug by pick and shovel at the gravel pit was loaded on horse carts and screened at the ballast area.
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This was dangerous work.:- Eastern Districts Chronicle.  27th October 1900.
News reached York yesterday morning of a railway fatality, which occurred at the ballast pits some three miles from Pingelly, the previous evening. From the particulars to hand a railway employee named George Gould, whilst engaged "breaking" trucks out of the ballast pit in question accidentally slipped down between the trucks and was crushed to death instantaneously.
The police authorities at Beverley were immediately apprised of the terrible casualty, and P.C. Campbell was despatched to the scene of the occurrence for the purpose of conveying the body into Pingelly, pending a coronial enquiry.
A post-mortem examination will be made by Dr. House upon his return from Katanning, and an inquest will follow.

​​The reserve was also the site of Pingelly Race Club's first racing track, which I suspect is in one of the dense wild oat patches. Race goers who came down by train were outraged by the exhorbitant one penny train fare!

The railway gravel pit forms a series of gently sloping north/south trenches in sandy/stony laterite on the northern side of the ridge. Perhaps horse carts ran down the trenches to be filled. The shire pit is clearly different because it occurs on loamy dolerite gravel to the south east and was more extensively mined using bulldozers. I think that the railway builders wanted ironstone gravel rock for the ballast that was sieved out from the the fines. An old railway pit at Yornaning was also stony gravel.

One side of the upmost railway trench will interest geology and landscape freaks like me because it reveals an ancient ironstone profile, which has been modified by time and climate change. More than a metre of ironstone overlies an ancient sloping mottled zone. From a distance the mottled zone looks like a normal dense white clay with iron-rich mottles, but it it contains light weight hard silcrete nodules in a compacted silty sand.
The profile suggests that over millions of years there has been a drier climate period when Proteceae was replaced by other vegetation - possibly eucalypts that created the silcrete nodules. I guess that they made good railway ballast.There is a 30 metre higher ironstone ridge to the southwest of this spot, so I think that the pit location was originally a sloping gravelly spur coming down from the ridge.

​A sign "Pingelly Understorey Seed Farm" at the entrance of a track to the pits appears to be a local Decade of Landcare Initiatve with ALCOA and Greening Australia. Sides of the pits have been planted to a range of mainly Proteaceae species, which are seeding prolifically.

The 148ha reserve is about 10km south of Pingelly where the Hotham River crosses the Great Southern Highway. Before European settlement, this area was particularly productive for Noongar people, having freshwater pools teeming with fish, gilgies, birds and animals. It is also the location of the ill-fated Pingelly town dam.
​Land clearing for agriculture caused the river and pools to silt and become salty, but the reserve is still an interesting and attractive place.
​I found this dolerite hand axe ,which fitted well in my hand, in the bed of the river. I left it in the reserve.

To enter the reserve turn into a side road/ parking bay at the sign just before you cross the Hotham River bridge going to Pingelly. All roads and trails through the reserve are dead end. About 400 metres along Lange Road is an unmarked track to the north. Cars can drive in to an obscure roundabout, which is a good spot to stop to explore for wildflowers. Soon after, the track becomes sandy - only suitable for 4WD vehicles. Keeping to the left the track ends at the Hotham River. Remains of the dam retaining wall is a 450 metre moderately difficult  walk through weeds and bush west along the river bank. 

This remarkable reserve has three main landscape types

• 1 The Hotham River, comprising a series of channels where the river     has changed course.


• 2 Adjoining sand dunes to the south.


• 3 An ephemeral pool adjoining the dunes then an upward slope of woodland, balgas and scrub overlying sand over gravel or clay and gravel soils.

  

To the east of the reserve is a large dune-surrounded saline wetland. Banksia sand dunes adjoining the river are uncommon in this area. Adjoining examples are Kokeby and the Yenyenning lakes to the north, Lake Yealering to the east, and Lake Toolibin to the southeast. Ancient land movements blocked and diverted ancient rivers to create lakes and wetlands at these places.
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This wetland marks the junction of the Hotham River South, Calcoran Brook, and Hotham River North on the northern edge of the Hotham River catchment. North and South Hotham rivers make a U-turn at the reserve to flow west/southwest, and there are unusual ephemeral ponds on the upside of dunes.

​So, what caused the Hotham South River to take a sharp turn here and why are there dunes and wetlands?  My simplified explanation follows.

What created this landscape?
This region is underlain by a  stable piece of continental rock called the Yilgarn Craton, which is mainly granite and gneiss, some of the world's oldest (over 3 billion years) rocks. As the craton formed, then joined and separated from others in supercontinent cycles, the bedrock cracked. These cracks are faults, and dolerite dykes (where magma beneath the continent has squirted up into the gaps. This area has more dykes than usual.
About 540 million years ago Australia was connected to the supercontinent Gondwana by Greater India to the west, and Antarctica to the south. Mountains associated with these connections eroded away to leave a subdued landscape. In this area, land sloped gently to the coast, but waterways often deviated along underground faults and dykes.
India gradually separated from WA creating a rift valley (the Swan Coastal Plain), which received sandy sediments via west flowing rivers from a divide around Corrigin.

​66 million years ago the Darling Range gradually rose up as a range of ridges east of the Darling Fault. An associated valley on the eastern edge of the range shows as a line of waterways roughly following the Great Southern Highway from Cuballing (Hotham River South), then up to Dalwallinu (Avon and Mortlock Rivers).
This and a possible east-west uplift just south of Pingelly, blocked rivers upstream of the reserve to create a lake. During periodic geological climate changes the lake filled and dried. In arid climate phases, sand blown from the dry lakebed formed dunes that were colonised by Banksias.
Eventually the river cut through a rise on the western side of the lake leaving the dunes and wetlands that exist now.

​The last feature is the seasonal pond on the upside of dunes in the reserve. Why would sandy dunes hold back water?
The answer is revealed in a radiometrics map. The red colouring in the image indicates a large dolerite dyke underneath the river channel and dune area. Dolerite weathers to reddish clay soils. In winter, subsurface water flowing down from sandier soils to the south meets less permeable dolerite clay and rises to the surface – hence a pond adjoining the dunes.
​Dolerite dykes are frequently found on the downside of salt areas, and may have also influenced the river direction.

Exploring the Reserve
Despite bring mined for sand and gravel and once having tracks associated with the pump and reservoir, there is a diverse range of lanscapes and vegetation which is mostly in good condition. I thoroughly enjoyed walking through the bush, but inexperienced walkers could become lost, and as in all our bush, kangaroo ticks may be a problem if one walks through vegetation in late spring, summer and autumn.
Orchid lovers can enjoy the range of spider and other orchids by exploring open land adjoining Lange Road.

Note that all bush tracks are sandy and potentially boggy. Only drive cars into area 2 to where there is a turn around spot. If using a 4WD please drive slowly and sparingly as this country is easily destroyed. Note, there is dieback in bush to the east of the reserve. Do not drive off tracks.

Area 1 gives a good cross section of the gentle slope down to the dunes. Mostly it is fairly easy and attractive walking country. Apart from a couple of small breakaways, soils are mostly sand over clay/gravel underlain at depth by granite or dolerite bedrock. Vegetation varies according to bedrock, with thicker bush and more orchids/other flowers on  paler sandy soils. 

​You can also often tell soil types by change in ant hill colour as you walk.There is a small group of Caladenia roeii clown orchids on the upslope of the road between the two low rises.

Area 2. Drive down the unmarked track and park at the (indistinct) roundabout.
2a is attractive open woodland on the upper side, which has a fine display of Chapmans Spider Orchids in September

2b is a short walk west from the parking loop. The ephemeral pond bounded by a line of Melaleuca phoenicia shrubs (ex Callistomen phoenicous) then dunes, is a geological oddity. It was once fresh, but has become slightly saline due to salt released from the subsoil of cleared land at the top of the slope. Most winters it hosts wetland plants, algae, and aquatic invertebrates. 

2c is a band of low sand dunes and interdunal hollows as you walk towards the river. Landscape and vegetation varies depending on depth of sand, with many different types of shrubland, but there are few orchids. Dunes consist of Banksia prionotes acorn banksia, Banksia attenuata candlestick banksia, and Allocasuarina huegeliana (rock sheoak) with little understorey.
​Interdunal areas are shrublands which vary greatly depending on the depth of sand over clay, and moisture availablity. They  are attractive in late spring due to the range of flowering species, which include some that are locally rare (e.g. Calytrix acutifolia, Grevillea anethifolia).
This has been a dry spring with fewer flowers than normal. 

Area 3 River.
The river area consists of the Hotham River, associated dry channels and fringing vegetation. The fringing vegetation is very weedy with lots of introduced grasses and Bridal Creeper. The old dam is about 450 metres west of the point where the track ends. LIttle remains apart from a line of posts, and to reach it is a scramble through uneven weedy land unless the river is dry and one can walk along the river bed.
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The dam and it's history is contained in this blog.

Area 4. This is a narrow strip of land containing a drain going between the highway and Power Street to the river. Lots of green spider orchids and flowering shrubs in September.

The devastating 2022 wildfire, which started near North Yiiliminning Nature Reserve has had an interesting consequence. In spring 2023 I discovered two very showy  native plants in burnt areas, which had not been recorded in the area.
Alyogyne huegelii and Solanum symonii are both recorded in Florabase as mainly coastal species.
How can this be?
In my opinion it is a by product of plant type, soil type, fragmented natural vegetation and changed fire management.

• Both species are fire ephemerals, which only live for 6  to 8 years, and need fire for seed to germinate.
• Both occur here on sloping heavy red soil from mafic (dolerite) rocks, which usually occurs as lines from cracks in basement granite rock. These soils are less common in our reserves, because they are good farming soils.
• Scattered wheatbelt reserves are not actively managed. Ockley and Birdwhistle reserves had not been burnt for decades

Alyogyne huegelii (Wheatbelt Hibiscus) is presently a dense understorey on a mafic loam slope in Ockley Nature Reserve. I clearly recall visiting this spot before the fire and taking a photo, which I later deleted because it was an unattractive view of scattered mallees on bark strewn ground with almost no understorey. It is now a dense mass of Alyogyne and other shrubs - Oh I wish I had kept that before fire image!

I also found several flowering Goodenia etheira plants on lateritic sand soil at Ockley Nature Reserve. This downy small flowered plant is only recorded further north in the Central Wheatbelt. I wonder how many other 'new discoveries' may be in the burnt area?

On light textured soils the main fire ephemerals have been Gyrostemon subnudis and Kennedyia prostrata, which have emerged in profusion at Birdwhistle Rock.

The name 'Velvet Bush' comes from a dense cover of short hairs on foliage and flowers.  They are commonly called paper flowers because of the papery sepals surrounding the small flowers.
Characteristics are

• Small to medium shrubs.
• Flowers and foliage are generally covered with stellate (star shaped) hairs, which can give them a furry or prickly appearance.
• Mostly pink/purple flowers composed of coloured sepals; (petals are tiny or absent.)
•  Flowers lack nectar, and are  buzz pollinated by generalist native bees, which feed on pollen released from stamens that form a column surrounding the style. 
• Dry fruit, which release seeds.

​Orriginally in the Sterculariaceae family, they have been amalgamated with other former families by taxonomists into a large Malvaceae family using genetic analysis. As an amateur I am confused. Florabase, has dual identification for these genera.
Top of page -Malvaceae / genus (Thomasia, Guichenotia, Lasiopetalum) 
Below  Family Sterculariaceae (Subfamily Byttnerioideae), Tribe Lasiopetalae.

​To the average person Thomasia and Guichenotia species are very similar. 
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Thomasia
​The most common species in this area are Thomasia foliosa and Thomasia macrocalyx. They both have small pink flowers composed of sepals with a single midrib, which are joined about halfway up to form a corolla tube. Although not showy, the flowers have a delicate interior.  They flower in June-July.

Thomasia macrocalyx is a tough hairy shrub with 1cm flowers, which I see in granite or dolerite rock soil. There are no petals, only pink sepals surrounded by green bracts. The smooth ovary is enclosed by large longish dark heart-shaped stamens, which open at the top. When native bees fold over the flower tip and buzz their wings, powdery pollen is sucked up through pores at the end of the stamens and lodge into the bee's body hair, and the flower stigma is fertilised by pollen on the bee from other flowers.

Guichenotia have have narrower leaves and several ribs in the calyx, but the difference is subtle. Luckily the two species in the Narrogin area, G. macrantha and G. micrantha which occur on sandier soils are very similar. The exterior of the sepals have  dark coloured hairs, which show up as a star shape when taking an photo of the flower with the sun behind it. Makes a great image.

Lasiopetalum
Thid genus can easily be distinguished from Thomasia and Guichenotia by the sepals, which lacks ribs and are split almost down to the base. I found Lasiopetalum microcardium at Harrismith Nature Reserve.

Now a few Red Herrings
Mugs like me can be fooled by similar looking plants.
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Cyanostegia lanceolata in the Malvaceae family has both petals and sepals and isn't hairy. But they do have light patterned , light coloured sepals, when the ring of dark purple petals  I have also been fooled by the petals, particularly when they are folded as being dark Malvaceae anthers. 
It flowers in September on gravelly soil and has stunning flowers, which glow from a distance with the sun behind them.  

Halgania anagalloides in the Boraginaceae family also has small  flowers with a calyx, blue petals, and a protruding ring of buzz pollinated anthers, which is also shared with Solanaceae (tomato) flowers. it is smallish shrub.

More information on identication
Seednotes 

My interest in ochre was rekindled recently, when I explored the Claypit Nature Reserve near Wickepin. Years ago as part of a mining lease there, the side of a mesa was excavated to get adjoining white and red ochre clays for brickmaking. The white section formed over granite, and red over a dolerite dyke.

​The importance of ochre for first nations people is summarised in this article on the ancient Weld Ranges Ochre mine.

An ochre pit at Dryandra National Park is one of over 440 recorded around Australia. For a nation this large, it is a small number, hence the value of ochre as an item of trade.

A good local example is the Uellelling Hill kaolinite mine east of Wickepin. The image below of a cutting in the exploration phase displays typical layers of an old laterite profile.

• ​The gravel layer contains most of the plant roots.
• The mottled zone layer is a transition to the pallid zone layer, which is stained by iron leaking down from the gravel layer.
• The pallid zone layer is decomposed bedrock, which has been weathered to clay and sand, and infilled with extra clay 

​The clay is a type of kaolinite called halloysite, which has many uses ranging from fine porcelain, paint additive, medicine and dentistry. Unlike other clays halloysite consists of microtubes rather than sheets.
​Electron microscope images of halloysite forming around bacteria lead on to a great story of soil development where plants lift minerals up from the depth in soil water, and microbes and fungi convert them to lateritic gravels, bauxite or clays.

​Pallid zone clay is also packed with salt, which was uplifted with soil water by native trees. When land was cleared, this salt washed down into rising groundwater and created our severe wheatbelt salinity problem.

White dams dotted around our landscape show the widely distributed pallid clay. If early Noongars had bulldozers, ochre would have been easy to get!
However, ochre only outcrops naturally on breakaway slopes. Granitic breakaways contain white ochre and less commonly yellow ochre (which contains an iron oxide called limonite). Red ochre contains an iron oxide called haematite which is mostly found on steep red-brown breakaways, which have formed off very iron-rich rocks such as dolerite.  Green ochre (containing a nickel oxide) is rare, only being found on ultramafic rock breakaway areas such as the Goldfields.
Good ochre contains very little sand.

​To see a jaw dropping breakaway, visit Buckley's Breakaway 70km east of Kulin

I found an easy way to make good ochre.

• Put the ochre sample in a bucket and add enough water to make liquid
• Swirl the liquid vigourously, then pour clay and water slurry off into another bucket leaving sand behind
• Leave the water and clay for a couple of days until the clay settles out leaving water above. Adding salt may help.
• Pour off the water leaving the clay slurry behind to evaporate to a creamy consistency

I take some samples in jars when I talk to visitors. The kids love it and as shown by the Foxyochrefoot image, even some adults indulge. it washes off easily. 

Further reading

• ​Ochre is of the Earth
• Exploring the biological dimension to pedogenesis with emphasis of the ecosoystems, soils and landscapes of southwestern Australia W. Verboom and J.F. Pate
• Why are plants and soils in the Narrogin area so diverse?