Function IsGreen(r As Range) As Boolean
IsGreen = False
If r.Count > 1 Then Exit Function
If r.Interior.ColorIndex = 4 Then
IsGreen = True
End If
End Function
The function will return true if the argument has a background color of
green (#4).
Then in J1 enter:
=IF(IsGreen(I1),"X","")
This method will not work of conditional formatting.