Pears won't get any bigger
I have an older pear tree that will only produce really small pears . Every year I have tons of pears but they will not get big . Added another tree to see if that would help nothing . Please help I'd love to have pears for my own self and not just for deer to eat .
Fertilizer should be applied rarely (once every few years) and is unlikely to be the cause. I would try removing some flowers - fewer fruit result in larger fruit. Also, trees with many branches block light and prevent fruit from getting bigger so pruning - up to 1/3 of the tree - may help. This does not look like a nutrient or pathogen issue from first glance.