Troy, those look pretty rough, did you check for images of the most common pear diseases
online? I have the impression many pears have scruffy looking leaves. Some still carried fruit while many of their leaves were not perfect at all. Especially when they are quite young and have been replanted into place.
The grass looks like there hasn't been tree growth for years. Many
trees need to establish specific mycorrhyzal funghi connections to flourish. On such a field they are a rare feature. And after a dry spell it can be that the rootsystem just is not developed
enough to support all the leaves. There might be an imbalance between the root/leaves ratio. As leaves evaporate they need a certain
root system to be in place if not the tree can drop its leaves as a emergency measure.
Sorry, i just give some general advice, i am no tree specialist, i hope someone can help you more specifically. I just want to say i worried about my pears as well and they carry quite some pears today.
Good luck