What's your question? Ask

I suspect water deficit and/or nutrient deficiency.
Soil fertility and water management are vital for plant health, flowering and fruit development.

Water a wide area not just near the tree trunk, cover the absorbing root zone which spreads as far as the foliar canopy and more.
Water deeply to wet the soil a minimum of six inches, preferably to 10 - 12 inches. Check this two to four hours after watering by digging down in a couple of spots to see how far the water infiltrated.
Mulch the soil surface to help retain soil moisture.
Fertilize spring and summer with a slow release complete organic fertilizer.

https://www.domyown.com/dr-earth-organic-all-purpose-fertilizer-p-9485.html

Without photos and more information about growing conditions and management, we can only guess with general assumptions.
A 40 year old pear tree will sometimes start to decline, depending on the stage of maturity, site conditions, soil and water management. A tree this age normally has developed size, a root system, foliar and woody mass that requires a great amount of water an nutrients. If irrigation and fertilization is inadequate, or if there are other plantings competing for water and nutrients, the tree will not be supported for essential uptake and metabolic processes.
Another factor is often wood decay and/or root rot. Wounds open the tissues to fungal infections resulting in wood decay and impairment of uptake. If the tree is in or near a lawn or other plantings that get frequent water, the over watering will create conditions for root or root crown decay, which of course impairs function and uptake of water and nutrients. Poor pruning can contribute to sunburn or physiological stress.

It will take about 4 to 6 years.

The disease may advance and cause branch die-back.

Apply a dormant spray with horticultural oil and fixed copper during the winter, a mixture of products like this, according to label directions:
https://www.domyown.com/southern-ag-liquid-copper-fungicide-p-8941.html

https://www.domyown.com/bonide-all-seasons-horticultural-spray-oil-p-1525.html

https://www.nature-and-garden.com/gardening/pear-tree.html
Pear trees can also get 'fire blight' a bacterial disease that enters through the flowers. Stand by weekly with a pole pruner and cut out blackened, "shepards crook" wilting tips below the blackened stem area, as they appear.
Attend to pruning, soil fertility and water management and mulching, and you may start to get some fruit.
Here's my favorite complete mineralized organic fertilizer:
http://www.soilminerals.com/Agricolas4-8-4_MainPage.htm
second choice may be available in your local garden center: Down To Earth or Dr Earth all purpose:
https://www.domyown.com/dr-earth-organic-all-purpose-fertilizer-p-9485.html

We actually have quite a few articles that will help you out here. This collection will get you started: https://www.gardeningknowhow.com/edible/fruits/pear

Unless you have something specifically for warm areas, then there will not be much need to winter them at all. I only recommend special treatment during the first year of its life. If this is a grafted tree that was purchased, and designed to fruit very soon after planting, then these trees will be ready to winter as long as you have gotten them in the ground and they have established already. This includes the willow. It will be hardy as well (and can become invasive).

Can you tell me a little more about the age of the trees, and about the environment that they are in right now? Pictures can help as well.