Two years ago I had several bushels of pears, and last year I barely had any. Should I be pruning the tree?
Yes, pruning can help. If the branches have become too crowded, the tree will fruit poorly.
What is the best way to treat or prevent fire blight in Asian pears?
The only treatment is to cut away infected limbs. Good cultural practices, particularly with watering, will help prevent the spread.
This article will help you: https://www.gardeningknowhow.com/plant-problems/disease/fire-blight-remedies-and-symptoms.htm
We just moved in to this new house and the backyard has four fruit trees (pears, apple), but the trees are covered in some kind of moss--dark green-looking, flaky stuff (similar to dandruff). There's hardly any leaves and I removed some of them by water spraying and manually taking them off the trees, but there just so many. What is it and what can I do to remove them? Are they harmful to the trees? I assume they are since the trees do not have any leaves. We are in the Tacoma, Washington area.
The moss like substance is most likely lichen. It is probably not what is causing the trees to fail, but is rather a symptom that the tree is ill as they do like to attach to trees that are unhealthy. Besides lost leaves, do the trees have any other signs of being ill so that we can try to identify it for you?
This article will explain more about lichen:
My pear tree was doing really well, but now all the leaves are curling and dried out, and some leaves have a red colour on them.
It may be fire blight. This article will have more information:
What type of insect causes large holes (about 1/2 inch in diameter) in tender pear tree leaves? What type of insect causes concave/round cuts (about 1/8 of an inch) around the edges of leaves?
Both kinds of damage sound like Japanese beetles. But occasionally, believe it or not, slugs also cause this kind of damage on tree leaves. If you are not seeing the pest, check the leaves at night for slugs.
I have two pear trees that are about two years old. They have good growth this year, but they both have limbs and leaves that turn completely black and wilt. I cut the black off and the limb starts to turn black as well. I can't think of any disease, and I am wondering if there is something in the soil. The trees are over 50 feet apart. Any ideas on what this may be?
It sounds like you may have fire blight. These articles will help you:
I have pear trees and this year there are just a few blossoms on them. My wife says that I am not pruning them properly. What is the proper way to prune pear trees?
This article should help you: