We have two granny smith type apple trees that set fruit and grow great right up until its time for the fruit to start ripening early august or late July then they completely drop their leaves and fruit and put on fresh leaves and blooms just before frost. Does anybody have any idea what s causing this or just bad genetics they get plenty of water .

How close to agricultural fields are you. Could be getting herbicide drift.

That sounds really strange to me. I'd suggest you contact a university extension facility from one of the big apple growing states. Maybe Washington State University in Pullman WA, or there might be a facility in Michigan (I think they grow a lot of apples there).

Are you fertilizing your lawn at that time?

Miles away these trees have been doing this for eight years

My wife dosnt fertilize the lawn or spray for weeds ever makes more work for her

There are enough big apple orchards in MO I bet the county ag agent will know or at least know who to contact

If its bad genetics i bet the wood will still cook a ribeye into something wonderful

Is there any brown spots on the fruit, or curel to the leaves? Is the bark "normal" looking on the trunk and branches? Need a bit more info.

My first guess would be heat and water stress. Late July early August equals hot. After the high stress period is over the tree tries to recover by setting new leaves when it is cooler. Are they in full sun or part shade? What type soil? You say it gets plenty water. Sandy soil drains out water pretty fast. Especially when it is hot.
Maybe get ahead of it this year about mid July. Dig into the soil to check the moisture level at 2 to 6 inches in a few spots around the drip line of the tree every few days. Water deeply as needed to keep up the moisture. A superficial spray of water won't do it.. Maybe mulch around the root zone to shade the roots from sun and hold in moisture.

They are on the edge of where water leeks out of a pondthe saturated area is just beyond drip line. The trees have grown lots of roots to it .the pond has made them out grow the peach trees planted at same time

They are full sun they look very healthy to me out growing the other dwarf trees we have by alot

I just wonder if they might be rootstock instead of grafted like they should be they came from lowes all that matters to them is its a tree in a pot

How much fruit are they putting on? May need to thin.

Crazy stuff here. I have never seen or heard of such a thing. Please let us know what your extension agency says.

When my apple trees get to much water (roots dont like standing water), the tree starts dying back from the tips. Specifically one growing on a ditch that catches water from the roof.

Agree with this.

Last year, some of my apple trees were attacked by bagworms, they lost their leaves, in part due to the worms and flowered again later in the Summer.

Keith

What you are describing is generally caused by stress of some sort. The regrowth of new leaves and blooms is the tree's response in an attempt to recover from the damage caused by that stress. There are hundreds of varieties of apple trees, many of which are selected to grow in specific regions and do not do well in other regions.
In your case, I would suspect heat stress. Heat stress can occur regardless of soil moisture content.