Trees not holding fruit

I am seeking help diagnosing possible problems with our fruit trees. We planted apples , peaches , pears 3-4 seasons ago. Bought from local nursery provider.
Since then I have attempted to establish mulch around trees and have been thwarted in my attempts by earthmoving free range chickens. The trees are in 2 different areas of our farm and have recieved different rates and combonations of horse , chicken , and rabbit manure. Some have recieved more grass /forb
mulch - top dressed , some have recieved more leaf mulch - mostly oak. The peaches in both areas have had fast leaf growth , this year they set alot of fruit and dropped most of it. The pears mostly alot of green growth few flowers and dropped most fruit. The apples are 2 Galas and one each of Arkansas black and one Granny Smith - they are sparsely leafed this year - no fruit.We are wondering if the chicken activity with constant manuring around trees and daily excavation of mulches may have produced over nitrogenation of soil. We have decided to paddock chickens in poultry net from now on - letting them in occasionally. The soil was pretty bad to begin with. Also the weather is unstable - we had false spring this year with late frost and then 2 weeks of dry during normally wettest time of year. Maybe it is just the age of the trees ? I know this is a rambling type of question but anyone who could shed a little light would be appreciated.

From your description, it sounds like your early spring caused the trees to bloom too early, and the later frosts finished the season for your fruit.

Thank You - It would seem that top dressing even rich material would not over fertilize and the chickens scratching it in would not place it too deep. My guess is that the age of the trees is a factor also.

I agree with John. The issue of an early spring with surprise frosts you are describing is a common issue and causes those similar problems that you are experiencing.

Even with young fruit trees that shouldn't be an issue especially if you didn't allow them to fruit the first year so they could better establish their roots.

Ok - Thank You