Chelated iron?

Is there a form of chelated iron that is safe to use??  For years I used the yellow powder that was a soluable form that could be use as a folar or as a soil drench.  It greened the plants up in a few weeks and also greatly reduced bug damage.  Originally I thought it was the healthier plant was fighting the bugs off better.  But recently read a bunch on chelation harming insects and also in particular earth worms.  Does it amount to a low grade insecticide instead?  Is there a chelation form that is safe or safer?

My soil is heavy clay with a native pH of 8.8 to 8.5.  It comes from a calcite bonded shale rock.  It is also high in sodium so the chloride answers tend to turn the soil to salty to grow anything.  With heavy organic matter I can buffer the pH down to about 7.3 to 7.5  without using chemistry by the truckload.  But that is about the best I know how to do.