this can be a giant problem ... when dealing with a monoculture.. and the main reason you should never plant one of anything.. all across an area ...

lets start by asking.. where are you ... how was winter.. spring.. summer .. etc ...

in my z5 MI i had a z4 4 winter.. tons of BW death in the area ... which was followed by torrential rains .... and then finishing with 6 to 8 weeks of drought ...

we might also like to know your base soil ... e.g. non draining clay???

the first looks dead.. move on ... find something diverse to fill the hole ...

i cant make heads nor tails of the second pic ... too straight down ... i think..

ken

ps: i see iron staining on the fence... they arent watered by a lawn sprinkler system are they???

The little shrubs in the front look like one of Japanese hollies. Are you sure that the larger ones aren't hollies, too, Ilex crenata or similar?

Judging by what appears to be Longleaf or Loblolly pinestraw, I'm guessing that you 'might' be in a southern location. If so, this sure does look like nematode damage, more common than people realize in warm climates.

Plant parasitic nematodes of different kinds attack a wide variety of plants, including holly and boxwood.

The tall plants are 6+ years old. The smaller ones we planted this spring. We are in the panhandle of Florida and our recent seasons were nothing out of the ordinary. Yes, there is a sprinkler using well water but it's always been there. What do we need to do or not do? Thank you!

I suggest that you take snips of the shrubs to your local extension office to have them properly identified. Your pictures aren't helpful in determining if the taller ones are a Japanese holly or boxwood..

While you're there, ask them about a nematode assay, a specialized soil test that will determine if there is a population of nematodes and what kinds.

Your location is....how shall I say it.....filthy with parasitic nematodes.

If they are contributing to your plant problems, they will tell you that there's nothing that the homeowner can do to get rid of them, but you can make their lives more difficult.