Riggs, Cynthia. Martha's Vineyard mysteries #13

"When 92-year-old poet/sleuth Victoria Trumbull takes her city-bred tenant Zack Zeller on a nature walk on one of Martha's Vineyard's conservation areas and shows him a mushroom she calls black trumpet of death, he's sure he's found the way to rid himself of his troublesome girlfriend, Samantha. But the mushrooms he's given Samantha end up on her daddy's dinner table, and Zack, one of the invited guests, is sure he's doomed the diners to an untimely death. Meanwhile, dead bodies are cropping up on the Island. The police have questions about the identity of the culprit and call upon Victoria Trumbull, who knows the Island and its inhabitants intimately. Will she be able to find the truth and clear the name of someone close to her before the murderer finds its next victim? In addition to giving us more of the eccentric cast of characters and quirky plot we love, Trumpet of Death, the 13th book in Cynthia Riggs' Martha's Vineyard mystery series, describes in loving detail little-known parts of the Island that visitors seldom see"--