Pecan nut loss
I have a ten year old pecan tree that is beautiful in form but loses the majority of its fruit. The pecans turn black in the shell and eventually fall off and are no good. It is a native pecan and has a fair size nut,
What is the cause of this and how do I go about treating the problem?
It sounds like you might have what is called "shuck dieback" but unfortunately, there isn't anything to be done about it.
You can read the descriptions here about shuck dieback, or maybe there is something else that fits what you are seeing better.
Here is another publication that is a spray guide for pecans. http://rains.agrilife.org/files/2011/03/fruit-and-nut-spray-schdule.pdf
It may be that you just have a beautiful tree that doesn't produce good nuts. That is the chance you take with a native pecan (that the genetics are poor.) Each nut on a pecan tree contains different genetics, so we really never know what we are going to get that way. That's why when we find a pecan we like, we name it and then graft it on to other rootstocks. And that's where we get the named varieties.
Let me know if I can assist you further.