Both dogwood and pear trees get anthracnose but, fortunately, they get different kinds. The soil is not affected in either case.
Dogwood anthracnose can be avoided if one plants a resistant kind. that list includes the kousa cultivars Milky Way and Steeple and the hybrid cultivars Celestial, StarDust, and Stellar Pink.
The potential for anthracnose of pear is somewhat limited,but, when it occurs, can affect the fruit; at which time it is called bull's eye rot. Sprays will be required in spring at petal fall and again 2weeks prior to harvest.
A pear tree will also require annual sprays for other, perhaps more common, diseases.
the, too,a fruiting European pear tree typically requires an additional European pear tree for cross-pollination. A solitary Asian pear will set fruit on its own but will have a more abundant crop of better quality fruit with a 2nd kind of Asian pear nearby.
The publications will provide further guidance for growing fruit trees:
- "Growing Tree Fruits and Nuts in the Home Orchard" - https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/ec819.pdf
- "Training and Pruning Your Home Orchard" - https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/pnw400.pdf.