Alice Clays. Average slope. Soil permeability. Inundation risk. Very low. Soil depth. Very deep; m. Wind erosion. Moderate

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Rodger Johnston
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1 Land system name: Land unit: Alice Clays AC1 General description This land unit represents the gentle lower slopes of an alluvial fan, which overlies an old lakebed clay. The depth to these clays may be very deep (>1.5m). Texture-contrast soils are predominant, with thin, sandy loam topsoils over reddish-brown clayey subsoils. Tall woodlands of Eucalyptus melanophloia (silver-leaved ironbark) predominate, with isolated occurrences of E. populnea (poplar box). Acacia excelsa (ironwood) and A. coriacea (desert oak) are common understorey species and Triodia pungens (gummy spinifex), Cymbopogon refractus (barbed wire grass), Digitaria brownii (cotton panic grass) and Bothriochloa ewartiana (desert bluegrass) are the dominant grasses. Regional ecosystem is predominant. Site characteristics Landform element Fan Site drainage Well drained Flooding risk Potential recharge to groundwater Present land use Grazing Average slope 1% Soil permeability Moderately permeable Inundation risk Very low Soil depth Very deep; m Susceptibility to land degradation processes Sheet erosion Moderate Gully erosion High Wind erosion Moderate Salting Land Unit AC1 - page 1

2 Representative site number: 510 Soil classification Australian Soil Classification CH AA AG EO - A E L O X Principle Profile Form Dr2.53-2/0/009 General soil description A texture-contrast profile with thin sandy loam topsoils over a reddish-brown light clay, which becomes sodic and slightly mottled below 1m depth. Soil profile morphology Horizon Horizon no Depth Description A Reddish brown sandy loam; No mottles; no coarse fragments; Massive; Very few (0-2 %) Fine (0-2 mm) Organic (humified) Soft segregations Dry weak; Clear to; B Reddish brown light clay; No mottles; no coarse fragments; Massive; no segregations; Dry firm; Clear to; B Yellowish red light clay; No mottles; no coarse fragments; Very few (0-2 %) Fine (0-2 mm) Ferruginous Nodules Dry firm; Abrupt to; B Strong brown light clay; Very few <2% Fine <5mm distinct red mottles; no coarse fragments; Few (2-10 %) Medium (2-6 mm) Manganiferous Soft segregations Dry weak; Soil chemical analysis Horizon Horizon no. Depth ph Gravel % Phosphorus Potassium Nutrient status A Deficient Satisfactory Very low 0 Nil - Very low N Y B Deficient Very low 0 Nil - Very low Very low N Y High Aluminium Salt content Organic matter Sodicity Slaking Dispersion Field sites within this land unit (see technical report for original site nos.) Site code Site type 374 DUSLARA Primary 503 DUSLARA Tertiary 504 DUSLARA Primary 505 DUSLARA Tertiary 506 DUSLARA Primary 507 DUSLARA Tertiary 510 DUSLARA Primary Summary of plant species within this land unit Species Abutilon otocarpum desert chinese-lantern, desert lantern, flannel weed, lantern flower Land Unit AC1 - page 2

3 Acacia coriacea Acacia excelsa Acacia sp. - Alstonia constricta Alternanthera denticulata Archidendropsis basaltica Aristida calycina var. calycina Aristida jerichoensis var. jerichoensis Aristida jerichoensis var. subspinulifera Aristida sp. Bothriochloa ewartiana Brunoniella australis Bursaria incana Calotis lappulacea Canthium oleifolium Carissa ovata Cenchrus ciliaris (1,5) Chamaesyce drummondii Chloris pectinata Chrysopogon fallax Chrysopogon sp. - Corymbia clarksoniana (Eucalyptus dolichocarpa) Corymbia dallachiana Corymbia sp. Crinum flaccidum Cyanthillium cinereum Cymbopogon refractus Cyperus fulvus Dichanthium sericeum Dichanthium sericeum subsp. sericeum Digitaria ammophila Digitaria brownii Digitaria sp. - Einadia nutans subsp. linifolia Enneapogon lindleyanus Enneapogon robustissimus Enneapogon sp. Enneapogon virens - Eragrostis basedowii Eragrostis lacunaria Eremophila mitchellii Eriachne mucronata Eucalyptus brownii x E. populnea Eucalyptus melanophloia Eucalyptus populnea desert oak, wirewood, dogwood, wiry wattle ironwood*, brigalow, bunkerman, ironwood wattle bitterbark*, fever bark, Peruvian bark, quinine, quinine bush, quinine tree lesser joyweed*, joyweed, rock joyweed red lancewood*, dead finish, eastern dead finish dark wiregrass Jericho wiregrass three-awn speargrass*, wiregrass desert bluegrass*, desert Mitchell grass, Tableland Mitchell grass, lagoon blue trumpet* hoary blackthorn*, prickly pine*, mock orange yellow burr daisy*, mallee burr daisy, yellow daisy burr myrtle tree,* wild lemon currant bush*, blackberry*, kunkerberry*, baroom bush, burrum bush buffel grass*, African foxtail, black buffel grass, Rhodesian foxtail, slender buffel grass caustic-weed*, caustic creeper, creeping spurge, flat spurge, mat spurge, spurgewort comb chloris,* comb windmill grass golden beardgrass*, golden-beard grass, ribbon grass grey bloodwood*, southern long-fruited bloodwood*, Clarkson's bloodwood ghost gum bloodwood Murray lily*, Darling lily, desert lily, flaccid lily, Macquarie crinum, Macquarie lily, native crinum, sandover lily, white lily veronia barbed-wire grass*, kangaroo grass, turpentine grass sticky sedge Queensland bluegrass*, silky bluegrass silky umbrella grass*, hairy umbrella grass, cotton panic, spider grass cotton panic*, cotton panic grass, woolly finger, cotton grass, silver spike grass climbing saltbush*, nodding saltbush canetop nineawn*, nine-awn grass*, prickly couch*, wiry nineawn, bottlewasher nine-awn bottlewashers* neat lovegrass purple lovegrass*, lovegrass, neverfail sandalbox*, bastard sandalwood*, budda, false sandalwood, sandalwood mountain wanderrie grass*, rock grass box silver ironbark*, silver-leaf ironbark, broad-leaf ironbark, silver-leaved ironbark poplar box*, bimble box*, egolla, nankeen gum, red box, white box Land Unit AC1 - page 3

4 Evolvulus alsinoides Evolvulus alsinoides var. decumbens Evolvulus alsinoides var. villosicalyx Fimbristylis dichotoma Goodenia glabra Grevillea parallela Grevillea striata Hakea lorea Hibiscus burtonii - Indigofera colutea Indigofera linifolia Indigofera linnaei Lysiphyllum carronii Melhania oblongifolia Melhania ovata - Oldenlandia mitrasacmoides Oxalis radicosa Panicum decompositum var. decompositum Panicum effusum Parsonsia sp. - Paspalidium constrictum Peripleura hispidula var. setosa Petalostigma pubescens Phyllanthus lacerosus - Polycarpaea corymbosa Polygala isingii Polymeria calycina Portulaca pilosa Pterocaulon sp. Rhynchosia minima var. australis Rostellularia adscendens Sclerolaena ramulosa - Senna costata Sida atherophora Sida filiformis Sida sp. - Solanum ellipticum Solanum ferocissimum Themeda triandra Tragus australianus Tricoryne elatior Triodia pungens Triodia sp. Triraphis mollis Urochloa piligera (Brachiaria piligera) Ventilago viminalis Vigna lanceolata var. lanceolata tropical speedwell*, baby blue eyes* tropical speedwell common fringe-rush*, fimbri sedge*, eight-day grass smooth goodenia* silver oak beefwood* corkbark, bootlace, corkwood, witinti, bootlace oak sticky indigo*, rusty indigo native indigo, narrow-leaf indigo Birdsville indigo*, nine-leaf indigo ebony tree*, red bauhinia*, small-leaved bauhinia*, northern bean tree, bauhinia, pegunny, Queensland ebony velvet hibiscus oxalis, coastal oxalis native millet hairy panic*, branched panic, diffuse panic, effuse panic, poison panic, two-colour panic knottybutt grass*, knotty-butt paspalidium, box grass, slender panic, graceful picnic grass fuzzweed quinine tree*, bitterbark, native quince, quinine berry, quinine bush pink bindweed* hairy pigweed* ragwort rhynchosia* dwarf justicia*, pink tongues fine sida potato bush*, hillside flannel bush, potato weed, tomato bush, velvet nightshade, velvet potato bush, wild gooseberry native tomato kangaroo grass*, red oatgrass small burr grass*, sago burrgrass, stockgrass, tickgrass yellow autumn lily*, yellow rush lily soft spinifex, gummy spinifex, spinifex spinifex purple plumegrass*, needlegrass hairy armgrass* supplejack*, vine tree, thandorah maloga bean Land Unit AC1 - page 4

5 Zornia muriculata subsp. angustata zornia* 1. Introduced plant 2. Consider for protection 3. Pending registration 4. Rare plant 5. Environmental weed 6. Endangered plant 7. Vulnerable plant 8. Agricultural pest * Wildnet preferred common name; Species in brackets refer to previously known name Special features This land unit is very similar to land unit TS2 in the Texas Fan land system, also with a silver-leaved ironbark-poplar box woodland, however the alluvium of the AC1 land unit overlies heavy clay soils of an old lakebed. Box woodlands support the greatest diversity of animal species of any habitat in the bioregion and are particularly significant for many woodland bird species that are declining in numbers in other parts of Australia, as well as granivorous birds, bats, terrestrial and arboreal mammals and some restricted reptiles. Implications for land use This area is adjacent to high-runoff country and may experience short-term flooding during very wet periods. A poor groundcover of vegetation increases the risk of surface water flow and sheet erosion after rain. The deep subsoils are sodic and have a high dispersion rating. The risk of gully erosion increases if runoff is confined to narrow channels and the sodic clays are exposed. If land use in the catchment area above this land unit allows increased water runoff, then the risk of gully erosion in this land unit and streambank erosion in land unit AC3 will also increase. This land unit is included in Land Management Unit 8. Land Unit AC1 - page 5

Important grasses for northern (n), central (c) and southern (s) Queensland

Important grasses for northern (n), central (c) and southern (s) Queensland Desirable perennial grasses Black speargrass Buffel grass Desert bluegrass/forest Mitchell Early spring grass Forest bluegrass