This tour features the unique Toolibin Lake with its reclamation program, bird life, picnic and toilet facilities, abundant spring orchids nearby; unusual wind deposited sandplain vegetation and some local history. Allow at least half a day for the round trip from Narrogin.

Stop 1 is the Lake Taarblin traffic bay on the right side of Yilliminning Road. This lake was fresh with salt sheoak and paperbark on the lake floor but it went saline in the 1950s.  Salmon gum (alkaline clay soil), red morrel (higher salt well drained loams and loamy gravels), York gum (loamy soils formed from fresh rock) here are common in these valleys.
This is a typical western wheatbelt salt lake, with sand dunes on the eastern side and a cliff on the west.

After leaving this spot turn right on to Yilliminning road and then left at Read road. The soils in this area were amongst the earliest taken up by local farmers. The farm house on the left about 4kms up this road is the original location for the Albert Facey’ house that is now in Wickepin town. Turn right at the T-junction and right again at the entrance to Lake Toolibin (Stop 2) and drive through York gum woodland and paperbark wetland to the car park.
This is the access point for a picnic area with gas BBQ, toilet, an interpretive centre and walk, and bird watching.
The 300 hectare lake is one of the last examples of a vegetated wetland lake left in the wheatbelt. Toolibin is an ephemeral or seasonal wetland that filled on average every 3 years from the 1960’s to the 1990’s). This cycle of wetting and drying has formed a wooded wetland with large stands of Melaleuca strobophylla paperbark and salt sheoak across the floor of the lake that provided an excellent breeding and feeding habitat for migratory waterbirds when the lake was full.
Agricultural land clearing has caused the rise of saline groundwater and associated salinity that resulted in bare salt lakes with dead trees like Taarblin.
Toolibin was steadily deteriorating until a recovery plan was prepared and a huge amount of investigation and work

Works include:

• Creation of a separator channel that drains salt water flows to Taarblin, but diverts fresh water into Toolibin.
• Pumping saline groundwater from the lake bed and discharging it in Taarblin.
• Revegetation of large areas of salt-risk soil in the catchment.
• Draining the saline wetlands above Toolibin to reduce salt accumulation.

The interpretive centre and signs on the interpretive walk describe the lake, its inhabitants, and the reclamation work. There has been a remarkable recovery in the health of the lake vegetation, but climate drying and drainage has reduced the frequency of lake fill. However bird watchers can see waterbirds on the channel leading into the lake and Lake Dulberning on the northern side of the entrance.

When you return to the Wickepin Harrismith road turn right and drive east for about 400 metres then park at a safe place on the side of the road (Stop3). This is a very orchid-rich area from July (greenhoods), September (spiders and others) to mid-October (sun orchids). Depth of sand over the clay varies greatly along the road here, ranging from Banksia prionotes (deep sand) to York gum (shallow) and broom bush melaleuca (winter wet), that have different understorey plants.

The Toolibin cemetary (stop 5) is on the ridge overlooking the lake. Only two graves can be seen, but the area also has interesting sandplain vegetation including the stunning Woolly banksia (Banksia Baueri). The marri trees are at the eastern edge of their range and have develop a low clumpy form as an adaptation to the lower rainfall environment. Interestingly they are much healthier than those in Foxes Lair due to seepage in the very sandy soil.

The grey sandy soil continues further along Cemetery Road and gradually changes to grey sandy gravel (formed from the sand by Proteaceae) further upslope on the left with interesting Kwongan vegetation like chittick (Lambertia inermis). The easiest way to see this is from Toolibin North Road.
Continuing over the ridge on Cemetery Road, vegetation changes to Acorn banksia Banksia prionotes woodland on yellow sand (stop 6). This is an older sand deposit than pale sand upslope, with the yellow colour created by Acorn banksia root secretions that enable them to access and recycle phosphate. Acorn banksia is a good sign of yellowish aeolian sands. Slender banksia Banksia attenuata that is also present becomes more dominant on grey sands. The soil changes to younger white sand dune heath near the bitumen cross road.

At the cross road you have the option of
a.Turning right and returning to Narrogin via Yillminning Road.
b. Crossing the road to the Toolibin townsite. Past the derelict Morris Minor and turn left up the gravel track. Upslope is safe to park and walk in on the left to see sandy gravel heath. Continue up the track and turn hard left on to The Toolibin North Road to return to Narrogin.
c. Crossing the road and turn right at the T junction to the Toolibin townsite. Nothing remains Peruvian pepper tree and bamboos that mark the school site.  If you then turn left along Line Road you will see a funky shack made of sleepers described here. After seeing the shack turn around and follow Line Road back to the bitumen road then turn left to return to Narrogin. 

Printable version of this blog below

I am sure that many of you have lain awake at night and pondered on this problem: "Why do salt lakes occur seemingly randomly along waterways, why are they round, and why do they often have dunes on one side and a steep slope on the other?.  Well ponder no more.

The answer is a bit complicated, but includes geology, earth movements, salt reserves in the subsoil, and long term climate variation.
​A good example is Taarblin Lake, which is two interconnected lakes.

​Lake Location
Geology: Unlike most other countries, we do not have permeable sedimentary rocks under our soils. East of the Darling Fault the underlying rock is a huge slab of continental (mainly granitic) rock that makes an impermeable basement below the weathered layer. This has been fractured by faults and is crossed by lines of dark dolerite type rock that weathers to a tight red clay. These two redirect or block groundwater flow. Many Great Southern lakes started when groundwater has been forced to the surface where these structures intersect waterways.
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Ground Movement: Australia a part of a supercontinent called Gondwana for hundreds of millions of years. About 280 million years ago, glaciation flattened the landscape, which later developed into a lateritic plain. When Australia finally separated from India on the west and Antarctica to the south, movement in the underlying basement rock caused two things to happen.
1. Great rivers used to flow south from as far north as Beacon in deep canyons to the south coast. The Antarctica separation caused the rise of a low east west ridge near the south coast called the Jarrahwood Axis that tilted much of southern WA down to the north and reversed the flow of these rivers. Resulting sluggish valleys with little slope filled up leaving a chain of lakes that only flow in a very wet year all the way to the Salt River past Quairading then the Avon to Perth.
2. The Salt River and other rivers like the Beaufort and rivers further north, were also active rivers that flowed to the coast when India was gradually separating from WA. 11 to 3 million years ago the Darling Range gradually rose upwards and blocked these rivers, causing them to back up as huge lakes that became the source for extensive sandplains to their south and east. A prime example is the Yenyenning lake system where the Salt River was diverted north to the Avon River.
These earth movements in conjunction with climate variation has resulted in large areas of aeolian soil in the wheatbelt. These include the Watheroo, Meckering/Cunderdin, and Corrigin/Quairading sandplains, and morrel blackbutt loams in the Lakes District.

Lake Shape: In very dry periods winds blew sediments out of the dry lake bed, causing the lake to become deeper, and producing dunes on the edge. When the lake was full, wind caused the water to swirl in a circular motion that cut away at the edges of the lake.

There have been large climate fluctuations over the last million years or so that are associated with glaciation elsewhere in the world. In arid periods plants died and very strong north-west winds that created dunes on the south-east side of the lakes and reduced their volume. In wet periods swirling water in the lake cut into the western side of the lake causing it to move west to form a cliff.
Lake Taarblin was considerably larger when the climate was wetter 3000-4000 years ago, but the eastern side has since been infilled by dunes and interdunal salt pans.

Lake Soils: 
When more water entered the soil than plants could use, salt was brought to the surface in groundwater causing salt patches. This is happening now after clearing bush for farm land, but it has also happened naturally in the past. Interestingly first Europeans in the district discovered that the existing lakes were mostly fresh, but did not fill as much as today.
You may have noticed that lakeside dunes are mostly sandy in the Western wheatbelt, but loamy with lime nodules in dryer areas. The reason for this is that lakes in the east tended to be dry and saline in arid periods with dunes created from the saline lake floor, whereas western lakes were full more often with sand washing in with the water.
You can tell the difference from the dunal vegetation. Acorn banksia (Banksia prionotes) and woody pear (Xylomelum angustifolium only occur on wind deposited sand.

However red morrel (Eucalyptus longicornis),  Kondinin blackbutt (E. kondininensis) and other salt tolerant eucalypts characterise the salty lakeside loams.

Further Information

The name Yilliminning comes from a Noongar word for nearby (now saline) pools.
Like Foxes Lair, and Railway Dam. this is a must-see spot for visitiors to Narrogin.
​Located 19 km east of Narrogin, Yilliminning Rock offers superb wildflower displays in the spring months, and an impressive 48 metre high granite inselberg which offers panoramic views over the surrounding bush and farmland. This historic spot also has a memorial salmon gum tree with information on George Brockway, a little known but amazing forester and conservationist. Dogs on leash are welcome.
There are picnic tables but no toilet. Fires and camping are not permitted. The rock is part of a larger reserve with interesting kwongan gravel wildflowers in October. Excellent birdwatching. 
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However there is more to Yilliminning than just the rock. Adjacent to the north is kwongan sandplain/ gravel country that has a wonderful array of wildflowers, and you can do a 17km return loop to Narrogin through scenic country to visit historic Yilliminning town site and Marramucking Well.

George Brockway Tree
This stately tree commemorates George Brockway, one of Australia's greatest foresters, who well and truly earned the nickname of being "the forgotten conservationist". The tree is one of a grove of magnificent salmon gums (Eucalyptus salmonophloia) that were once widespread in wheatbelt clay valleys.
As Forester-in-charge of the WA Forests Department's wheatbelt and goldfields regions during the 1930s, 40s and 50s, George was notable for his passion for the trees of the WA inland, and his promotion of them for conservation, farm planting, townsite beautification, ornamentals and timber.
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A few of his greatest projects are:

• The establishment of numerous bushland and conservation reserves in the wheatbelt and goldfields.
• He built the State's first fire lookouts and created the first effective forest firefighting system.
• He developed the first nurseries raising seedlings of our native trees, which led to overseas export of seed for revegetation in countries like Africa
• Establishment of arboreta and the mallet plantations at Dryandra and Highbury.

​Read about his life 

Surrounding Wildflowers
The open sheoak woodland has great spider orchids in September, particularly Chapmans spider orchid Caladenia chapmanii that varies in colour from blood red to mainly yellow or white, Green spider orchid Caladenia falcata and similar but uncommon Smooth-lipped spider orchid Caladenia integra. Magnificent plants!
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This blog shows highlights here in November.Great spot in the early morning or evening.

Marramucking well can be found about 30km from Narrogin, 5km north of the intersection of Marramucking Road and Boundain North Road. It is worth visiting as part of a loop with Yilliminning townsite and Yilliminning Rock that is described in this blog The meaning of the name is lost but it was one of an east/south east line of important watering places for Noongars, early settlers and sandalwood cutters.
It was also particularly important for Noongars as an inter tribal meeting place,but now has a dark history for them. In the 1880's an epdemic of measles and other introduced diseases caused mass deaths here and at Wolwolling Pool, which heralded the end of their well organised society.
An aerial view shows the reason for the well’s location.
Rocks on either side of the well are granite that has weathered to sandy surfaced soils. In the image below you can see a raised line passing below the well that represents a ‘dolerite dyke’. This dark rock is a part of the Binneringie dyke suite that goes from Quindanning to Coolgardie and includes the southern rocky red soil ridge in Foxes Lair.
O.E. Pustkuchen, author of ‘The Way through; The Story of Narrogin’ writes of playing in sticky red clay below the Marramucking Well. This red clay, formed from dolerite acts as an underground wall that interrupts groundwater passing down the sandy slope, and forces it to the surface as seepage. The water goes down again after crossing the dyke back to granite. This is a very common cause of seepages, wells and lakes in the district that were once fresh but are now generally saline.

There is a concrete picnic table and the Historical Society renovated the area many years ago, but the style placed for crossing the fence has rotted away.

The well a standpipe and the remains of a water trough can still be seen with the ubiquitous pepper tree.
Have you ever noticed that these trees occur on a great many historical sites in the wheatbelt to the goldfields?
With or without a commemorative stone they are the only trace of many schools, houses and sheds from a time when most WA inhabitants lived in the country (a pox on big cities!).
I thought that Schinus molle was called the Japanese pepper, but it is actually the Peruvian pepper, an amazingly drought tolerant tree from the Andes. So shady and soft, it is apparently listed as an aggressive weed, but I haven’t noticed them seed or sucker.

Fruit and almond trees are also seen around old homesteads as many farmers at the turn of the century had orchards to supplement their income, with some fruit being exported to England.

Further to the north is a heap that is all that remains of a mud-bat house that had a single divided room with a narrow addition on each end.