The curling leaf symptoms pictured are not due to a fungus. We see what looks like clusters of aphids underneath the leaves, and this is a very common cause of leaf curling on a variety of trees and shrubs, and a very common plant pest in general. No treatment is needed for the aphids because plenty of beneficial insects will eventually eat them, but preventative fungicide and insecticide applications (for other issues) are generally needed for fruit trees like apple to protect the tree's health and to protect the harvest from damage that might ruin fruit. You can learn more on these pages:

• Growing Apple and Pear Trees in a Home Garden
• Home Fruit Disease and Insects (it's a long document, but you can search it for "apples")

Once the tree has more foliage, you can pluck off the very curled leaves if they are too much of an eyesore, but otherwise they are still feeding the tree and do not need removal. Using a strong spray of plain water from a garden hose, aimed at the leaf undersides where the aphids are located, can blast them off the plant, and some of the ants tending them as well.

Periodical cicadas are not going to be emerging in Maryland this year, with the tiny exception of a small portion of St. Mary's County. No landscaping protection is needed for cicadas.

Miri