Dead Autumn Olive in Windbreak

Hey all, wanted to pick your brains about something.  About 8 years ago, I planted out a windbreak along the roadside consisting of black locust, nanking cherry, and autumn olive.  Zone 6A.  All was well until this spring where the autumn olive, grown to 8-10’ tall, all died back, some with just some top leaves but the rest are dead-dead, no shoots.  Thing is, it was just the autumn olive, the nanking’s and black locusts are fine.

I am at a loss as to why this happened.  The only connection I could make is the farm across the street sprayed their corn last year and the township had some spraying going on for phragmites.  Could this be a targeted herbicide causing this issue?  Road salt could have been a contributor but if that was the case the other plants would have suffered, too.  I have English walnut, persimmon, and seaberry directly behind this windbreak which appear unaffected so I guess the windbreak did its job if that’s the case.

I’d love to hear your thoughts on this, I’m baffled, and honestly don’t know if I should replace them with the same or put in something different.

That's strange that it would hit just the autumn olive so selectively. Only thing that jumps to mind is if there was some kind of herbicide drift from the road at some point, they can be surprisingly sensitive to that even when other species shrug it off. Did anything change roadside last year, any spraying nearby?

Joao Winckler wrote:That's strange that it would hit just the autumn olive so selectively. Only thing that jumps to mind is if there was some kind of herbicide drift from the road at some point, they can be surprisingly sensitive to that even when other species shrug it off. Did anything change roadside last year, any spraying nearby?

The corn field across the street sprays every year and that’s one of the reasons I planted out the windbreak, but the autumn olives thrived every year until now.  Maybe they changed herbicide or applied more heavily?  Also, the township sprayed for phragmites last summer but there aren’t any within a half mile of me so that seems unlikely.

It’s a mystery to me.