Element

Iron (Fe)

Manganese (Mn)

Zinc (Zn)

Copper (Cu)

Extraction Method

DTPA

DTPA

DTPA

DTPA

Low

<2.5

<0.6

<1.0

<0.6

Adequate

2.5 - 5.0

0.6 - 2.0

1 - 1.5

0.60 - 2.0

High

>5.0

>2.0

>1.5

>2.0