The first apple disease caused by a virus was reported at Cornell University exactly one hundred years ago, yet significant gaps remain in our understanding of the impacts of viruses on apple production. These include the effects of viruses on apple production in high-density orchards, as well as their natural transmission routes. Results of a field trial conducted to evaluate the effects of several viruses on the production of apples in a high-density orchard are presented here. Interestingly, this field trial revealed that the poorly understood phenomenon known as “rapid apple decline” was not associated with virus infection, despite previous reports of association between declining trees and virus infection status. Finally, results of seed transmission studies are presented which demonstrate that six apple-infecting viruses are seedborne in cultivated apple, though it remains unclear whether these seedborne viruses can be transmitted to the progeny of infected trees.