In this area these beautiful wildflowers are shrubs that usually occur on sandy and gravelly soils and tend to flower in late Spring. Most have tubular flowers, and often have hairy/woolly vegetation and / or aromatic foliage.
The following clues indicate that flowers are superbly adapted for bee and fly pollination.

• Generally white, mauve, pink colours which suit their vision, often with darker spots to provide contrast
• Petals form a corolla tube  lined with stamens  that rub pollen on to an insect as it enters to get nectar
• The tube ends in two or 5 irregular lobes, and provide insects with landing pads and attracts their attention.
• Many flowers have tiny hooks or lobes on anthers that push pollen onto the insect.

For laymen like me identification can be a nightmare as there has been considerabe change and amalgamation over the years. In old books they have been divided over the decades into groups such as Labiatae, Laminaceae, Scrophulariaceae, Verbenaceae, and Chloanthaceae.
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I use the following rules of thumb to help me identify genera in this area

Prior LAMIACEAE (FOXGLOVE) FAMILY

Genus Microcorys - white and pale pink, tube shaped flowers with a helmet shaped upper corolla lobe, three crinkled lower lobes, and a five lobed calyx. Two fertile stamens and two infertile ones (staminodes)

Genus Hemigenia - white pink and purple tube shaped flowers with a helmet shaped upper corolla lobe, three lower lobes, and a two lobed calyx.Four fertile stamens. Leaves have rounded or blunt ends.

​Genus Hemiandra - white and pink classic mint shaped flowers with a two lobed calyx, a narrow corolla tube with two upper lobes and three lower lobes, and four fertile stamens. Hemiandras have distinctive sharp pointed leaves without petioles and opposite placement on the stem. Hemiandra pungens (Snakebush) is most common locally.

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​Genus Westringia - white, classic mint-shaped flowers with a five lobed calyx, a narrow corolla tube with two upper lobes and three lower lobes, and two fertile stamens. I usually see Westringia rigida in open woodland.

​Prior VERBENACEAE / CHLOANTHACEAE (MINT) FAMILY

Members of this family are most common in drier areas, and have drought tolerant dense woolly vegetation. There are only one or two species in each genus in this area, which vary greatly. They all occur on gravelly kwongan heath.

Dasymalla terminalus is a tallish shrub adjoining the Harrismith airstrip, which has spectacular white flowers in October.

Chloanthes coccinea is notable for its bright red flowers and sessile glandular leaves. The colour anthers and stigma extending from the corolla tube suggests that this species is also pollinated by birds

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​Cyanostegia Lanceolata is a tallish shrub that is very different to other Lamiaceae genera, and can be mistaken as a member of the Malvaceae family. Bright yellow stamens and the pistil are highlighted as they project out from the black corolla tube to attract buzz pollinating native bees. After pollination the corolla tube sheds leaving the calyx, which expands and glows in the sun.

I often see fallen trees as I travel around the wheatbelt. I think that trees are falling much faster than others are growing to develop critical nesting and refuges for our native birds and animals. Wind blowing from cleared land is stronger than uncleared forests, and trees endure more stress events now due to increased heat and reduced rainfall.

I recently discovered a large Silver Mallet Eucalyptus falcata, which had blown over to reveal its amazing root system. In this district Silver Mallets occur on our oldest land surfaces-shallow ironstone remnants of ancient upland mesas. I usually find them in reserves on the highest points of lateritic upland boundaries surrounding river catchments. 

​The fallen 20 metre high beauty had been supported by a six metre diameter plate of dense roots and very long feeder roots that snaked out from the central plate. All of this was in about 40 centimetres of gravelly loamy sand soil over a dense ironstone pavement

A closer look at the underside of the root disk revealed that it was mainly a dense mat of shallow feeder root. Round spots in the mat were thin sinker roots, which had managed to penetrate cracks in the ironstone layer

Most trees and shrubs have a dimorphic root system, which has a taproot, which grows straight down to the water table, from which it obtains water for the plant; and a system of lateral roots, which obtain nutrients from superficial soil layers near the surface.The image of a dried root of a young tree that was probably killed by fire displays these features.
Proteaceae plants such as banksias and hakeas have dimorphic root systems, but they rarely occur in adult eucalypts.

After studying root systems of fallen eucalypts I discovered that most have minor tap roots, usually several small sinker roots below a ring of feeder roots. This makes sense because our ancient soils often have shallow topsoils over hostile subsoils.
There are a couple of great examples on the Breakaway Walk in Foxes Lair, which have fallen over but remained alive with side branches taking over the function of the main stem.

The mallee region of wheatbelt WA is characterised by a subdued landscape of mallee woodland on hard setting duplex soils. Recent research has shown that many eucalypts have root systems that create a layer of dense clay subsoil to exclude other plants. Young mallees initially have a tap root like other eucalypts that develops into a  woody lignotuber ('mallee root'). Lateral roots generate a hard clay barrier layer and sinker roots extending down through it water holding clay below. Over hundreds of years the taproot/lignotuber rots to allow water to rapidly flow into the soil and a lateral sinker root network, which pumps soil water up and down the soil profile. After rain these roots move water below the clay barrier to deny competing plants and store it. In summer the network pumps water back up for the mallee's use. Amazing!

For an interesting description of tree root systems, read this web page.
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Shallow root systems are certainly not limited to Australia. As with Australian trees, tap roots are inhibited by hostile subsoils, some for other reasons such as pines on permafrost. 

Lechenaultia formosa, Red Leschenaultia is one of my favourite wildflowers. Partly because the patch I irrigate and till in Foxes Lair rewards me with exquisite flowers that remind me of mini red Manta Ray heads (yep I am a dreamer!)
​The 'tongue' is an indusium - a cup at the top of the style and surrounding the stigma that collects pollen from the anthers  while still in the bud. It is another example of secondary pollen presentation, which is used by many Australian plant species to ensure precise pollen placement, and is a feature of the Goodeniaceae genus.
In the images below I have cut petals away to show the process involved in loading and presenting the pollen as a flower develops.
Stamens are joined in an anther ring (connate) halfway up the unopened bud. The cupped indusium grows up to the anthers and collects pollen before growing through them to the mouth of the flower. 

​As the flower opens the indusium bends to present a package of pollen to insects that presumably crawl in to find nectar.
After the pollen has been removed or dies, a white growth of stigma cells emerges on the side of the indusium to harvest pollen from visiting insects. Voila, pollen delivered and collected from a precise spot on the target insect's body!

Indusium shapes vary and could remind one of the human eating plants in 'The Day of the Triffids' novel. The one on the common Lechenaultia biloba, Blue Leschenaultia is a ripper. Last year I found dainty little Lechenaultia tubiflora in deep white sand at Ockley Nature Reserve.

Here are more Goodeniace examples.

Goodenia caerula appears to be an exception because an insect has to push through closed petals to find the indusium. I suspect that this could be a moisture saving aid because this species flowers on gravel soils in November.

On the other hand all Dampieras also have hidden indusia, but in a small fold in two petals and called an auricle.

Genus Anthotium also hides the indusium in an auricle. Dainty priority 3 threatened species Anthotium odontophyllum, Durells Anthotium flowers on clay soils at the Claypit in November.

​A string of reserves centered on a chain of salt lakes in the Arthur River stretches down from Lake Toolibin (the last remaining wheatbelt freshwater lake). The rest of the lakes are saline, but were fresh or brackish up to the 1950’s.

​​The area was surveyed for farming from 1904 to 1907. The Nomans Lake hall was built in 1911 and is still in use. The surveyor Oxley passed through the area in the 1890’s, although prior to this, shepherds and sandalwood cutters were in the district. Abundant food and water in the lake must have been very important for Noongar tribes, but no evidence remains. Diseases spread by contact with Europeans decimated these people and destroyed their social structure in the 1880’s, and access to the lakes was progressively reduced by land clearing and farming.
Local farmer Stan Prideaux’s recollection of the lakes during the depression states ‘One pleasant recollection from those days was the state of the environment. The lake systems were generally full each year. Timber in and around the lakes was alive and the water only slightly brackish. Waterfowl abounded in the lakes – swans, ibis, heron, duck, water hen and other. Ground birds and birds of the forest were also plentiful – plovers, ground larks, sky larks, curlew, parrots, galahs, swallows, quail, black and white fantails – to mention some’. Source: Nomans Lake a Collection of Memories.  Heidi Astbury and Lyn Chadwick 1987.
Today the lake beds are bare or dotted with dead trees and salt tolerant plants, but vegetation in surrounding uncleared land is often in excellent condition. The area is seldom visited because few lakes can be reached by road and surrounding saline areas are uninviting. With much walking I discovered starkly beautiful and varied salt lakes in a range of landscapes with surrounding areas of saline flats and often attractive healthy woodland.  

​The area is a great example of the WA Wheatbelt’s ‘reversed’ rivers’ - In most areas of the world, rivers start as small active streams in mountains and become larger and more sluggish as they approach the coast, but many large wheatbelt rivers start in subdued  plains and become more active as they pass through the hilly Darling Range to the ocean.
The Arthur River is ancient and begins in the old plateau sandplain landscape east of Toolibin before passing between uplands associated with the Binneringie Dyke to the North and a large ridge associated with the Buchanan River to the south. A chain of lakes merges into the extensive Narrogin Valley flats, then narrows as it passes through the Darling Range to Join the Blackwood. The river system tributaries and associated uplands frequently run in northwest-southeast and southwest-northeast patterns, which reflect fractures in the underlying crystalline bedrock caused by repeated supercontinent collision and separation cycles.

Why are there lakes in this particular area? here are some clues.
There is a paleochannel (buried river) system 300m wide and 40m deep beneath Toolibin lake extending approximately five kilometres upstream in a north-westerly direction. Paleochannel sediments are about three million years old, which coincides with the Darling Range uplift.
The lake system ends above the intersection of the Yilliminning and Arthur Rivers. From that point the Arthur River channel becomes more actively flowing and highly saline. Much of the valley containing the lakes has mostly healthy natural vegetation and mild salinity. A farmer told me that the lakes filled upstream from Little White Lake. Perhaps this coincides with flooding of the Yilliminning River.
An exaggerated terrain map I created shows that from Ibis to Noman lakes water passes through a gap between uplands on either side. I think that faulting and uplift  associated with the Darling Range uplift reduced river slope where it joined the Yilliminning River and promoted lake formation. Some lakes are separated by dolerite dykes.

​Lake Descriptions
The following hyperlinks contain information on Lake Toolibin and salt lake formation as illustrated by Lake Taarblin. 
Cars can drive to the southern end of Taarblin from Williams Kondinin and Lakes roads. The lake was a popular water skiing, duck shooting, fishing, and picnic spot before it became saline. Taarblin is a large lake, which is separated from Ibis Lake to the south by a barrier formed by a dolerite dyke and adjoining heat-hardened granite. The dyke is exposed on the steep red clay southeast bank. and boulders from the adjoining granite are artfully scattered on the shoreline. If you look closely you will find shells of tiny snails, which I also found in other lakes in the chain that fill most often. Good spot for landscape artists and photographers

Taarblin overflow passes through a  culvert under Lakes Road  into a  channel to Ibis Lake. In the early days, the road could only be traversed by a boat in winter. Remains of the old Astbury house can be seen by the water channel. Ibis Lake's name suggests that this lake once teemed with waterbirds (I found shotgun cartridges and snail shells). The lake is now bare and saline. A salty depression East of the lake contains a soak that has become saline. This is bounded by a dolerite rise (which was Bill Astbury's favourite paddock).  Water from salt land to the east enters another inlet on the south of Ibis lake and exits again a bit further along.

From Ibis Lake water enters and exits the south side of Billy Lake. All lakes have surrounding sandy dunes covered by salt tolerant shrubs, Casuarina obesa-Salt sheoak, and scattered paperbark trees and shrubs, but the dunes are larger around Billy Lake. I think this is an indication that the lake fills less frequently. This lake has no defined waterway from the north apart from a man-made drain. Runoff appears to come from the wide valley above in flood years via numerous gilgai depressions covered by paperbark, broombush and salt tolerant vegetation. The lake itself is bleak, with a silty floor dotted with dead trees and bushes.   

Once again, water exits Billy Lake and enters Bokan lake from the south, which is repeated downstream. The lake chain also tends to lie on the northern edge of the wide valley.
​Aha, this is probably due to another geological influence on the lake system. Likely causes are the South Coast Jarrahwood Axis uplift, and the Australian Plate slowly subsiding beneath Indonesia, causing the continent to tip down to the north. Ancient rock platforms on the south coast indicate that the coast has risen by about 130 metres in the last 20 million years or so. 

Bokan Lake was the first lake in the chain with water I visited, and is quite scenic. It receives water quite often from creeks from a  large catchment to the north. I managed to drive down to the lake from Lakes Road through a saline flat on a  summer only track, but this is very boggy country. 

Runoff from Bokan Lake reaches Nomans lake, which adjoins the Wagin Wickepin Road. This lake was a popular recreation area in the early settler days.
White Lake is a forbidding site - a large circular and mostly bare area with a compacted floor ringed by low dunes. The lake directly adjoins a rise on its north side and only receives water when the main channel to its south flows. Clouds of acrid dust were blowing fom the lake bed when I visited.

Little White Lake is the last lake in the chain. Water flows into it frequently from a large and mostly fresh water catchment to the north that flows through a salty flat dotted with dead trees to reach the lake. Despite the forbidding stretch of salt land one needs to cross to reach the lake,it is a very interesting area. I found several old nesting boxes, which had been nailed to trees on the eastern side indicating that someone valued the wildlife here at some time. 

The northen end of the lake floor contained typical dead trees and bare saltland, but an aerial image shows numerous mounds in the southern part. The sandy mounds are about 1.4 metres high surrounded by a shallow ditch. The mounds were created by the local branch of the WA Field and Game Association 1n 1983 as a WA Fisheries and Wildlife experiment to grow vegetation for waterfowl habitat. I also found a few old swan nests in clumps of dead trees in the lake.

I was surprised by the variation and amount of healthy woodland surrounding the lakes. There was Salmon Gum, York Gum, and Red Morrel woodland most likely growing over dolerite dykes, and mixtures of Wandoo, Salt Sheoak, York Gum, paperbarks and rushes.intermixed with saltland heath. I enjoyed seeing the vegetation changes as I walked through, and would enjoy seeing which seasonal flowers occur in the growing season. It is a pity that the area is difficult to access.
Woodland examples are shown below. 

​The Narrogin arboretum was one of more than 50 demonstration plantings established by the then Forests Department, throughout the wheatbelt, in the 1950’s and 1960’s. The arboreta were developed to evaluate a range of local, regional, Australian and overseas species that were thought to have promise for planting in the wheatbelt and goldfields, with a focus on species for quality timber, dust control and for windbreaks.
Before this the only tree seedlings available were Sugar Gum-Eucalyptus cladocalyx, Brazilian Pepper-Schinus terebinthifolius, and Kurrajong-Brachychiton gregorii from the Forest Department Hamel nursery. I often see the first two trees at early farm homesteads. LIvestock don't eat them.
The Narrogin arboretum, smaller than most, was added to over several years as new species became available, with the last trees being planted in 1969.
In the last couple of years well established tree in the arboretum have died. As part of a search for possible causes I obtained the DBCA file containing the original planting map, and a report on arboreta success by George Brockway in 1965.
Brockway never ceases to amaze me: he is truly a legendary forester and conservationist, who initiated the arboretum project with a series of trials in 1946 as the Kalgoorlie District Forestry Officer.

The Narrogin arboretum is more difficult than most to evaluate because it lacks a uniform soil type and planting date, and has an ephemeral creek running across its centre. Plantings range from 1955 at the eastern end to 1966 at the west. Soil types range from Marri loamy sand to the west grading downslope to York Gum clay loam in the east, and species have been roughly planted according to their reputed appropriate soil type.
Another complication is the warming and dryer climate. E. rudis-Flooded Gum trees, which  grew on in sandy surfaced soil on the southern side of the arboretum have all died except for a clump below a street drain outlet on Range Road. Other apparently healthy large trees in Foxes Lair abruptly died in the last two years, including a large Tasmanian Blue Gum. Similarly a row of E. Lane-pooleii trees (with the exception of one adjoining a drain) on loamy sand on the western end of the arboretum died in the past 3 years. They survived for 70 years as attractive mini-versions of trees in their natural range. ​Despite this, some WA higher rainfall species have thrived and many Goldfields species have done poorly. Why do E. gomphocephala-Tuart (southwest coastal sand), E. preissii-Bell Fruited Mallee (south coast species) do so well here?

• ​Brockway noted that imported species tend to be more successful in arboreta than locals, because insect pests do not recognize them as being edible. This is very evident at Narrogin in excellent growth of most Eastern States trees, and perhaps the Tuarts. He specifically mentioned wood boring beetles, but termites and stink bugs are the main culprits at Narrogin. The damn stink bugs are everywhere. When I plant seedlings in Foxes Lair I have to cover susceptible species with fly mesh for a few seasons to stop the growing points being sucked dry.

A thriving local exception is E. longicornis-Red Morrel which is found on salty loams and red clay-gravelly clay soils, but an adjoining Salmon Gum row is sickly.
​Brockway also noted that tree plantings were more successful after a crop than in cleared bush. Factors involved include

• ​Seedling response to fertilizer, particularly phosphorus.
• Retained subsoil water
• Fewer insects

​​Pines, and Casuarina obesa-Salt Sheoak have grown very well, but some pines are approaching the end of their life.
Most mallees have thrived in the arboretum, particularly on the upper slopes. Oil mallees planted on heavy soil (E. kochii subspecies kochii and plenissima) have persisted on the heavy soil but are attacked by stink bugs. E. kochii subsp. kochii did not persist on a sandier row.

​Mallets are another story. These WA eucalypts are obligate seeders, which lack lignotubers and tend to grow on very hard setting and heavy clays, and  breakaway slopes. E. spathulata-Swamp Mallet, was a Brockway recommendation, and I would have agreed twenty years ago. A once magnificent row (pegs 159-163) have mostly collapsed from termite infestation. The original map showed an earlier planted  row further east in the arboretum on clay soil, which are just termite eaten holes in the soil.

 Other failed mallets are E. diptera, E.campaspe, and E.gardnerii. Three species have persisted: local E. astringens-Brown Mallet, E. Stricklandii (a straggly Goldfields species), and E. platypus- Moort.
​Mallets appear to have a shorter life than trees and mallees.
E. spathulata has exquisite bark in autumn, and one of them was the official hugging tree. Alas, no longer.

Moort is a small mallet which forms dense thickets on hard setting southern clay soils. It has adapted well to fire by excluding other plants while living and shedding huge amounts of seed when burnt.
Plants in the Narrogin arboretum row are continuously infested by termites that cause branches to snap regularly, but the moorts still thrive and flower prolifically.

​Brockway also highlighted seedling survival problems due to overgrown seedlings with coiled roots. I don't think that it was a problem at Narrogin, but the problem persists today. My DBCA buddy Peter White who assists urban landcare groups in his spare time is frustrated by nursery produced overgrown seedling with coiled roots, which are a widespread cause of revegetation failure.