I live on 10+ mostly acres in southern MD,, we have had a flock of 15-20 chickens for the last 15 years, and harvest multiple deer off the property.
My soil is clay. When I built the house I added 2-3" of top soil to the ~3/4 acre we cleared. Never able to really get grass to grow. 10 years ago I planted 3 apple trees out front. dug 3 holes on the slope, 5-6' round, 3' deep and back filled with top soil and aged horse manure, then planted 3 semi dwarf apple trees, the voles ate the roots and the trees fell over. I replanted with wire cages buried around them,, they did not die, but never really grew. 10 years later 1 have harvested 1 golf ball sized apple.

This year I decided I would try berries and grapes. I bought Black berry, Raspberry, blue berry and grape whips from Lowes/Home Depot. I dug 8" round x 10" deep holes and filled with top soil and aged compost (black soil) from the chicken run and planted the whips.
The grapes died within 3 days, the leaves wilted and the "stem" went limp and flopped over.
I bought a soil meter from HD (PH and fertility),, I think it may be more of a gimmick than a useful tool??

Thinking I just don't have a green thumb and should stick to hunting deer??
Any advice is welcome.

Hello Doctor...............
I've been looking through the Garden Regions forums trying to figure out where Oklahoma gardeners belonged.................
and I ran across and read your post.

I spent 34 years as a Landscape Architect designing gardens in Oklahoma City. Your growing conditions sound somewhat similar to ours.

It sounds like you need a good talk with a soils expert.
I would strongly suggest you contact the office of your county's extension agent... and ask to make an appointment for a visit from an Agronomist... or, at least, the name of a reputable Agronomist in private practice.
Get a complete analysis of your land and soil.

Respectfully Yours;
jathton

By the way... a gardener I respect very much once said, "I never give up on a plant until I've killed it three times."