Chapter 6
Calcium and Magnesium
|
Table 1. Soil Test Ca And Mg Calibrations For Peanuts
on Soils of The Southeastern Coastal Plain by State Soil Testing
Laboratories Using Mehlich-1 Extractant |
|
|
|
Ca Ratings2 |
Mg Ratings2 |
|
State1 |
Target pH |
Low |
Med |
High or adeq |
Low |
Med |
High or adeq |
|
|
|
mg kg-1 |
|
Alabama |
|
|
|
|
|
|
|
CEC 4.6 |
6.5 |
8-88 |
89-150 |
>150 |
0-12.5 |
-- |
>12.5 |
|
CEC >4.6 |
6.5 |
8-88 |
89-150 |
>150 |
0-25 |
-- |
>25 |
|
Florida |
6.5 |
0-250 |
-- |
>250 |
<15 |
15-30 |
>30 |
|
Georgia |
6.0 |
0-2503 |
-- |
>250 |
<15 |
16-30 |
>30 |
|
North Carolina4 |
6.2 |
NI5 |
NI |
NI |
|
|
|
|
Mg-% Sat.<10 |
|
|
|
|
0-61 |
-- |
>61 |
Mg-%
Sat. 10 |
|
|
|
|
0-30 |
-- |
>30 |
|
South Carolina |
6.5 |
0-200 |
201-400 |
401-1,000 |
0-16 |
17-30 |
>30 |
|
Virginia |
6.5 |
0-360 |
301-720 |
>720 |
0-366 |
37-72 |
>72 |
1References: AL: Cope et al 1981;
FL: Hanlon et al. 1990; GA: Plank 1989; NC: Tucker and Rhodes
1987; SC: Clemson Univ. 1982; VA: So. Regional 1984.
2Values are frequently reported as “pounds per
acre,” assuming 2 xl 06 pounds per acre furrow
slice.
3Based on a sample from the upper 2 to 3 inches of
the fruiting zone after peanuts are established.
4North Carolina uses the Mehlich-3 soil extractant.
Rating uses extractable Mg and % Base Saturation of Mg.
5NI=No Interpretation for this element.
6“Low-”= 0 to 12, “Low” = 12.5
to 24, “Low+” = 24.5 to 36 mg kg-1. Mg is
recommended only at “Low-” and “Low” ratings. |
Document Prepared by:
Leigh H. Stribling, lstribli@acesag.auburn.edu
Alabama Agricultural Experiment Station
Auburn University |
