Help ... Trees disappear in the distance

As image is showing, with procedural foliage, mor far away I go, and more trees completly disappear showing only strange stains instead of trees. I changed LOD parameters in mesh details, and this solve same issue for others trees but ton for this.
Is there a way to fix this or, at least, have a camera High detailed quality image vision which show trees coretcly?
Many thanks

did you find any solution ?
i solved it by
enable PRESERVE AREA ( under enable nanite enable support option ) that works if you are using nenite .