Q.BARTLETT PEAR TREES
I have 2 20 year old Bartlett pear trees. They have been producing fruit for many years but most of the fruit falls off when very small and the remaining fruit never gets to even half of the normal size. I have never been able to harvest or eat any of this fruit. I was ok with it until last week when, while biking in downtown Indianapolis, we came across a Bartlett pear tree that is just planted in front of a business. It was loaded with full size fruit that is just delicious! Now I am seriously wondering what I have been doing wrong all these years. Do you have any suggestions please? Thank you for your kind assistance.
Laura L. England

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