Table A.1 (continued)
Rating
Very high
High
Medium
Low
Very low
A3: Ratings for aluminium, iron, silica and sulphur contents, and soluble salts
Acid oxalate—
extractable
Al (%)
>3.0
1.0–3.0
0.5–1.0
0.2–0.5
<0.2
Fe (%)
>2.0
1.0–2.0
0.5–1.0
0.2–0.5
<0.2
Si (%)
>0.5
0.15–0.5
0.05–0.15
<0.05
Pyrophosphate—
extractable
Al (%)
>2.0
0.8–2.0
0.4–0.8
0.1–0.4
<0.1
Fe (%)
>1.2
0.6–1.2
0.3–0.6
0.1–0.3
<0.1
Dithionate-citrate—
extractable
Al (%)
>2.0
1.0–2.0
0.5–1.0
0.2–0.5
<0.2
Fe (%)
>4.0
2.0–4.0
1.0–2.0
0.5–1.0
<0.5
Phosphate—extractable
sulphur or sulphate (µg S/g)
>150
50–150
15–50
5–15
<5
Soluble salts
Conductivity (millimho/cm)
1:5 extract at 25 °C
>2
0.8–2
0.4–0.8
0.15–0.4
<0.15
Salts (%)
>0.7
0.3–0.7
0.15–0.3
0.05–0.15
<0.05
Table A.2 Ratings for soil physical properties
Physical parameter
Very low
Low
Medium
High
Very
high
Potential rooting depth
a (cm)
<20
v. shallow
20–40
shallow
40–80
mod. deep
80–120
deep
>120
v. deep
Soil dry bulk density (g cm
−3
)
<0.6
0.6–0.9
0.9–1.5
1.5–1.8
>1.8
Total porosity (%v/v)
<35
35–45
45–60
65–75
>75
Macroporosity (%v/v)
<5
5–10
10–20
20–25
>25
Penetration resistance
b (kPa)
<1000
1000–
1500
1500–2200
2200–3000
>3000
Degree of packing
c (kPa)
<500
loose
500–1000
very
friable
1000–2200
friable
2200–3000
firm
>3000
very
firm
Permability
d (mm h
−1
)
<0.4
extremely
slow
0.4–4
slow
4–18
moderately
slow
18–72
moderate
>72
rapid
Profile readily available water
a (mm) over potential rooting depth
or 1.5 m depth
<25
25–50
50–100
100–130
>130
Soil depth
d (cm)
<20
very
shallow
20–45
shallow
45–100
moderately deep
>100
deep
a From A. D. Wilson and D. J. Giltrap 1984. Soil evaluation and classification system for orchard crop production. Soil Resources Report SR6. Soil
Bureau, DSIR. 54p
b
Adapted from E. Griffiths 1984. Interpretation of soil morphology for assessing moisture movement and storage. NZ Soil Bureau Scientific Report
74, 20p
c Determined using Singleton Blade and 6 mm tip penetrometer after E. Griffiths 1984. Interpretation of soil morphology for assessing moisture
movement and storage. NZ Soil Bureau Scientific Report 74, 20p
d
Adapted from S-map ratings
316
Appendix A: Ratings Tables for New Zealand Soil Properties
Rating
Very high
High
Medium
Low
Very low
A3: Ratings for aluminium, iron, silica and sulphur contents, and soluble salts
Acid oxalate—
extractable
Al (%)
>3.0
1.0–3.0
0.5–1.0
0.2–0.5
<0.2
Fe (%)
>2.0
1.0–2.0
0.5–1.0
0.2–0.5
<0.2
Si (%)
>0.5
0.15–0.5
0.05–0.15
<0.05
Pyrophosphate—
extractable
Al (%)
>2.0
0.8–2.0
0.4–0.8
0.1–0.4
<0.1
Fe (%)
>1.2
0.6–1.2
0.3–0.6
0.1–0.3
<0.1
Dithionate-citrate—
extractable
Al (%)
>2.0
1.0–2.0
0.5–1.0
0.2–0.5
<0.2
Fe (%)
>4.0
2.0–4.0
1.0–2.0
0.5–1.0
<0.5
Phosphate—extractable
sulphur or sulphate (µg S/g)
>150
50–150
15–50
5–15
<5
Soluble salts
Conductivity (millimho/cm)
1:5 extract at 25 °C
>2
0.8–2
0.4–0.8
0.15–0.4
<0.15
Salts (%)
>0.7
0.3–0.7
0.15–0.3
0.05–0.15
<0.05
Table A.2 Ratings for soil physical properties
Physical parameter
Very low
Low
Medium
High
Very
high
Potential rooting depth
a (cm)
<20
v. shallow
20–40
shallow
40–80
mod. deep
80–120
deep
>120
v. deep
Soil dry bulk density (g cm
−3
)
<0.6
0.6–0.9
0.9–1.5
1.5–1.8
>1.8
Total porosity (%v/v)
<35
35–45
45–60
65–75
>75
Macroporosity (%v/v)
<5
5–10
10–20
20–25
>25
Penetration resistance
b (kPa)
<1000
1000–
1500
1500–2200
2200–3000
>3000
Degree of packing
c (kPa)
<500
loose
500–1000
very
friable
1000–2200
friable
2200–3000
firm
>3000
very
firm
Permability
d (mm h
−1
)
<0.4
extremely
slow
0.4–4
slow
4–18
moderately
slow
18–72
moderate
>72
rapid
Profile readily available water
a (mm) over potential rooting depth
or 1.5 m depth
<25
25–50
50–100
100–130
>130
Soil depth
d (cm)
<20
very
shallow
20–45
shallow
45–100
moderately deep
>100
deep
a From A. D. Wilson and D. J. Giltrap 1984. Soil evaluation and classification system for orchard crop production. Soil Resources Report SR6. Soil
Bureau, DSIR. 54p
b
Adapted from E. Griffiths 1984. Interpretation of soil morphology for assessing moisture movement and storage. NZ Soil Bureau Scientific Report
74, 20p
c Determined using Singleton Blade and 6 mm tip penetrometer after E. Griffiths 1984. Interpretation of soil morphology for assessing moisture
movement and storage. NZ Soil Bureau Scientific Report 74, 20p
d
Adapted from S-map ratings
316
Appendix A: Ratings Tables for New Zealand Soil Properties