Table 3. Combined iron sulfate and elemental sulfur requirements for the treatment of individual trees and shrubs by the soil application method.*

 
Trunk diameter (inches)
Number of 1 to 2 inch diameter holes made in soil within the drip line
Pounds of combined elemental sulfur and iron sulfate
  
1

4
0.5 - 1.0
2

6
1 - 2
4
8
3 - 6
6
12
8 - 12
8

16 - 24
12 - 16
10

25 - 30
16 - 20
15

30 - 40
20 - 30
20
40 - 50
30 - 40

* Holes should be 12 -18 inches deep.

  
 
Updated 7/15/02