Well of course we google. LOL You know google is one of my good friends. I had come across that same article...and according to that ash is an important part of your pets diet, BUT it also states that The minerals contained in ash include calcium, iron, magnesium, sodium and zinc, along with trace amounts of many others.
ZINC??? and many "others"? Again huh? Does that apply to the ash in bird foods too? Or does it depend on where the ash comes from?
Like Tess, I only use the Abba during molts, but if the ash content is harmful I wouldn't even want to use it then.
Of course birds in the wild don't get "perfect" food. We humans have exposed wildlife to all sorts of bad things.
Point being the wild ones don't have as long a lifespan partly do to US ...and OUR captive birds DO have a choice of going organic if WE as their parents choose to give them as healthy a diet as possible.
So, your hubby did bring up a good point tess, but kind of made the wrong point. LOL If that makes sense.