Q.Apple and Pear tree disease
I just purchased some fruit trees from the nursery (Asian pear and Yellow Delicious apple) in April. Looks like there is some sort of disease on them…possibly fire blight? Some of the branches/leaves are dying and turning black. Can someone tell me what I should do to save my fruit trees? Thanks!

I would check the trees carefully for any other signs or symptoms to help pinpoint the issue.
Did this issue start right after planting?
Is the soil right for your trees?
Watering is very important in newly planted trees. The soil should be moist but never soggy. Make sure the soil is well draining.
Most greenhouse or garden centers will guarantee new trees for 1 year.
https://www.gardeningknowhow.com/edible/fruits/apples/apple-tree-diseases.htm
https://www.gardeningknowhow.com/edible/fruits/pear/fixing-pear-tree-problems.htm
http://web.extension.illinois.edu/cook/downloads/9210.pdf