Sr.
No.

item

Low

Medium

High

1

Organic carbon used as a
measure of available nitrogen.

Below 0.5 p.c.

0.5 to 0.75 p.c.

Above 0.75
p.c.

2

Available N by alkaline
permanganate method in kg/ha

Below 280

280 - 560

Above 560

3

Available P by Olsen’s
method in kg/ha

Below 10

10 - 24.6

Above 24.6

4

Available K in kg/ha

Below 108

108 - 280

Above 280

5

pH

Acidic

Normal

Alkaline
above

Below 6.0

6.0 to 8.0

8.0
(9.0 harmful
for most crops)

6

Conductivity
(total soluble salts)
millimhos

Below-1

Normal

1-2

Soluble salt content critical for germination.

2-3

Salt content critical for the growth
of salt sensitive crops

Above 3

Severe injury to most crops.