Well, I read-up on the different kinds of injectors, how they work, etc. It still doesn't register in my very limited intellect - it has the smell of problems and trouble to me.
I think, instead, that I'll leave tractor lanes between every six rows like I do now, and continue to apply the fertilizer with the trailer sprayer (100 gal tank, pto driven). Sitting on the tractor, using an ordinary garden hose nozzle with the pressure set at 20#, I can run 6 rows on each pass (three on each side) - applying exactly the right amount of fertilizer by just eyeballing it. That's what I've done for years.
On the other hand - I was a painting contractor, as was my father, and I remember as a teenager in the early fifties his refusing to use the new-fangled paint rollers and making us continue to use those miserable 12" wall brushes until the competition forced him to change. And I remember when airless sprayers first came out - backward like my father, I continued with the archaic, wasteful, unhealthy air sprayer until my best hands threatened to quit and the competition was killing me!
I guess I'm being the same way about fertilizer injectors!
LOL
Jack