Catherine spotted these last year: small but healthy young sword ferns, a rare welcome and hopeful exception to what we have seen in eight years of the sword fern die-off – which is that sword ferns do not naturally re-establish themselves from spore in the forest at Seward.
For the most part, sword ferns colonize open ground on mineralized soil before the forest canopy forms, then plants each live very long lives (“a thousand years is not out of the question” – D. Barrington). Direct sunlight and bare, rich soil are the usual preconditions.
Years of close observation throughout Seward’s fern dead zones fits this model. (The research on germination and establishment are summarized here.) Catherine’s observations complicate the received wisdom – and offer some hope.