On 27 Aug 1990, while driving just east of Middle Island, New York, Leo Shapiro (1995, p. 114 to first two lines of p. 115) heard "what sounded like a weak Orchelimum song." Upon investigation he realized there were many singers in roadside trees and recognized the song as that of O. silvaticum. He collected three males to confirm the identification. Subsequently, he returned to the site on 21 September and 14 October 1990, 3 October 1992, and 6 October 1993 and, each time, confirmed the population's continued survival. On surveys of several similar sites in central Suffolk County in 1992 and 1993, he was unable to locate any additional populations. After considering several alternative explanations of the O. silvaticum population he observed on Long Island, Shapiro (1995, p. 116, last few lines of last complete paragraph) concluded, "a recent human introduction, perhaps eggs on nursery stock, seems to be the most likely explanation for the presence of O. silvaticum on Long Island."
In email, Wil Hershberger reported O. silvaticum as occurring in the following counties: Berkeley (17 August 2017) and Jefferson (23 August 2017) Counties, West Virginia; and Frederick (25 August 2018) and Washington (1 August 2017) Counties, Maryland.
