SFS15

Location: PVI Hamilton

Australian Soil Classification: Ferric-Sodic, Eutrophic, Brown CHROMOSOL
Northcote Factual Key: DY3.22
Great Soil Group: Possibly brown podzolic.

Geology: Tertiary/Quaternary basalt.
General Landscape Description: Southerly aspect, simple slope (1%), relatively elevated position in a gently undulating basalt plain. Land surface moderately gilgaied, with puffs at 2-4 metre intervals and a relative relief of 100 mm or less.
Soil Mapping Unit: Monivae gravelly loam (slope phase) (Martin and Maher 19).

Site Description: Pasture paddock. Proposed site for raised bed research (Phil Newton). The face of the pit showed gilgai ‘puff’ features, while the sides and rear of the pit showed gilgai features associated with ‘hollow’. There was a thick A2 horizon in the hollow and a very high (>80%) amount of buckshot (3-10 mm) which was mostly magnetic, irregular rounded or sub-rounded (pitted).

Site SFS15 Landscape

Soil Profile Morphology:

Surface Soil

A1 (Ap)	0-20 cm	Very dark greyish brown (10YR3/2), greyish brown dry (10YR5/2d) ; fine sandy clay loam; weakly to moderately pedal; fine to medium sub-angular blocky to polyhedral; firm consistence dry, weak consistence moist; clear change to:	Site SFS15 Profile
A2c	20-35 cm	Dark brown (10YR3/3), puff - greyish brown dry (10YR5/2d), hollow - light greyish brown dry (10YR6/2d); gravelly loam; with hard magnetic ferro-manganiferous concretions (3-10 mm); pH 5.6; clear boundary change to: NOTE: In the hollow there is a smooth and wavy boundary up to 50 cm in depth.
Subsoil
B21t	35-100 cm	Yellowish brown (10YR5/4) with fine yellowish brown (10YR5/8) and brown (10YR4/3) mottles; light medium clay; fine buckshot (>10%); pH 6.6; clear change to:
B22t(ss)	100+ cm	Grey (N6) with brownish yellow (10YR6/8) mottles; light olive brown (2.5Y5/3) with yellowish brown (10YR5/8) mottles; medium heavy to heavy clay; no buckshot; horizon cracked to base of pit and fissure traceable through B21 above; stress cutans (slickensides) on ped faces; pH 6.6.

Puff and Hollow.

Subsoil Mottling.

Key Profile Features:

• Lateral variation in the soil profile features association with gilgai microrelief.
• Strong texture contrast between the surface (A) horizons and the subsoil (B21) horizon.
• Ferruginous nodules (‘buckshot’) in subsurface (A2) horizon.

Horizon	Horizon Depth (cm)	Exchangeable Aluminium mg/kg	Exchangeable Acidity meq/100g	Field Capacity pF2.5	Wilting Point pF4.2	Coarse Sand (0.2- 2.0 mm)	Fine Sand (0.02- 0.2 mm)	Silt (0.002- 0.02 mm)	Clay (<0.002 mm)
A2	20-35	<10	9.6	28	10	20	34	22	21
B21	40-60		14	50	33	2	8	7	81
B21	60-80		14	49	31	3	9	7	78
B22	100+		13			3	9	12	73

• Plant available water capacity (PAWC) is considered to be medium (estimated at 110 mm) in the upper 100 cm of this soil profile.