Hi, welcome to BYC!
I do not prefer to use DE.... for reasons stated already, but at least let me give you my take...
In 5 years I haven't felt the need to treat for worms or parasites. All they do is dirt bathe. A lot of it has to do with conditions. Some parasite load is normal and the birds build a resistance to them. It only becomes a problem when there is an overgrowth of said parasite, cocci for example is always present with chickens but not always a problem. With proper pasture management or run management it is much less of an issue. Now, I have wild birds and animals in our yard on a regular basis and that is often where certain things will come from. So do not do extra stuff to attract other birds or animals.
I also don't treat my dogs for fleas or ticks and my vet insists I must use something in this area. But at last visit said "nice flea control, no ticks. What do you use?"
Yes, DE is a porous rock that has microscopic shards that are supposed to scratch the surface off of bugs which dehydrates and kills them. And this same DE floats into the air where when inhaled can only possibly do what? That's right, create those same perforations on the esophagus and inside the lungs of the chicken. And yourself for that matter.
Not just when they are dirt bathing. But they carry around a nice layer of it and shake out every now and then, sending a nice poof into the air.
DE as a wormer, I am sorry... is bogus. The composition of DE is
80 to 90% silica, with 2 to 4% alumina (attributed mostly to clay minerals) and 0.5 to 2% iron oxide.
Silica is sand essentially. DE is a soft stone and very crumbly, you can break it with your fingers. So I figure by the time it goes through the crop and makes it to the intestines it is fairly disintegrated and rubbed smooth in the gizzard. Also have you read the ingredients on your feed bag? Many feeds include DE already and I go out of my way not to buy them. (Again the dust cloud when I pour it) I think if DE worked as a wormer that would be one huge marketing draw that feed companies would advertise heavily. So your good intentions likely had no effect on the worm load of your birds...
I guess if I got to the point where it was my last resort... well, I would consider something else.
I haven't actually researched wood ashes yet to see if they are effective or safe. Just like you presume the DE effective at worming because you don't have a problem, others may do the same for ash. So I will look into it in case it really is useful and I ever do have the need for it.
The uptick in flying things might be seasonal or no DE may have an effect if it's keeping things dryer. Knock those weird flying things down and feed them to your birds! They are the ones that have to worry about being bit.
Maybe consider using some Neem oil or something to that effect? I haven't tried that yet but it has been touted for its effectiveness in the garden at past control. I would probably find out if that was safe and try it if I need to.... hope I can remember it by then.
Oh.... to keep pest population down in soil, I use chickens!!
I would consider ditching the product instead of looking for other applications. But I do realize that what works for one person at one location might not work for another somewhere else. And that's what makes BYC a great community is all of us being able to share what does or doesn't work for us and why.
One last word... on organics. It's nice and all, but even arsenic, lead, and dog poo are organic!
Point being, just because it's organic doesn't make it good for you. Like wise there may be some thing that even though they aren't organic actually would be good for you.
Oh and HAPPY BIRTHDAY TO YOUR FLOCK!!!
Hope I was helpful. Of course those are only my opinions and what works for me.