GHF11a

Location: Macarthur

Australian Soil Classification: Vertic, Eutrophic, Brown CHROMOSOL
General Landscape Description: Level Plain
Site Description: Flat
Land Unit: Warrakbook Basalts
Geology: Quaternary basalt

General Land Unit Description: This land unit consists of gently undulating basalt plains in the Macarthur area. In some drainage lines, the basalt has been dissected sufficiently to expose the underlying sediments. The soils on the basalt plains are commonly Brown Kurosols or Chromosols, intermixed with Sodosols, particularly on the lower slopes and drainage depressions.

Soil pit Man98 1-4 landscape

Soil Profile Morphology

A1	0-15 cm	Dark brown (10YR3/3) fine sandy clay loam; weak granular structure (10-20 mm) parting to weak granular structure (2-5 mm); very weak consistence when moderately moist; many medium roots; clear and smooth transition to:	Man981_pro.jpg
A2	15-35 cm	Brown (10YR5/3) fine sandy clay loam; weak polyhedral structure (20-50 mm) parting to weak granular structure (5-10 mm); very weak consistence when moist; common very fine macropores; areal porosity 0.5%; many medium roots; clear and smooth transition to:
Subsoil
B1	35-45 cm	Brown (10YR5/3) with common medium faint light yellowish brown (10YR6/4) mottles, light clay; weak polyhedral structure (10-20 mm) parting to weak granular structure (5-10 mm); weak consistence when moist; common medium ferruginous nodules; few very fine macropores; areal porosity 0.05%; common fine roots; clear and smooth transition to:
B21	45-90 cm	Yellowish brown (10YR5/4) with few medium distinct red (2.5YR4/8) light medium clay; moderate polyhedral structure (20-50 mm) parting to moderate granular structure (5- 10 mm); weak consistence when moist; few coarse ferruginous nodules; common very fine macropores; areal porosity 0.05%; few very fine roots; gradual and smooth transition to:
B22	90-140 cm	Light brownish grey (10YR6/2) with few medium distinct yellowish brown (10YR5/4) and red (2.5YR4/6) mottles, medium clay; strong lenticular structure (20-50 mm) parting to strong polyhedral structure (10-20 mm); weak consistence when moist; few coarse ferruginous nodules; common very fine macropores; areal porosity 0.1%; few very fine roots.
	140-340 cm	Roots observed to 270 cm, heavy grey clay, moderately strong lenticular structure.
C	340-420 cm	The C Horizon, extremely coarse weathered basalt (up to 1000 mm), live roots many medium roots observed. Basaltic rocks (up to 150 mm) observed. The abundance of rocks in increasing with depth with virtually all rock at 420 cm, resulting in an impeding layer to root growth.

Soil Profile Characteristics:

-	pH	Salinity	Sodicity	Dispersion
Surface Soil (A1 horizon)	Very Strongly Acid	Low	Non-Sodic	None
Subsoil (B21 Horizon)	Slightly Acid	Low	Non-Sodic	None
Deeper Subsoil (80-140 cm)	Moderately Acid	Low	-	-

Chemical and Physical Analysis:

Horizon	Horizon Depth (cm)	pH (water)	pH (CaCl₂)	EC dS/m	Organic Carbon %	Total Nitrogen %	Exchangeable Acididty meq/100g	Exchangeable Cations				Coarse Sand (0.2-2.0 mm) %	Fine Sand (0.02-0.2 mm) %	Silt (0.002-0.02 mm) %	Clay (<0.002 mm) %
								Ca	Mg	K	Na
								meq/100g
A1	0-15	4.7	4.2	0.06	3.2	0.24	13	1.8	0.61	0.09	0.06	34	33	16	10
A2	15-35	5.7	5.0	<0.05			6.2	2.0	1.4	0.06	0.10	32	34	15	18
B1	35-45	6.3	5.6	0.06			7.8	3.1	2.8	0.08	0.27	30	24	11	33
B21	45-80	6.1	5.8	0.14			10	3.4	5.8	0.14	1.0	16	15	8	61
B22	80-140	5.9	5.6	0.20

Profile Described By: Ian Sargeant, Paul Feikema, Martin Clark and Kiet Quach, 30th October 2000.

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