Wild stock Castanea dentate (American Chestnut) were planted at the edge of a forest clearing in western Maine in 1982, and four had grown to a height of 13 m and diameter breast high of 39 cm by 2014. They showed no sign of disease and were producing annual seed crops. The seeds had been spread in the surrounding forest by animal-made seed caches placed up to at least 300 m from the source; 238 surviving offspring (119 of them one-year old) of the planted trees were located in 139 groupings. Of the surviving seedlings, 110 were growing singly, although groupings ranged from two to 20. At least six of the animal-spread seeds had, by 2014, produced 2-6.5-m-tall saplings that were growing up to 70 cm per year. Experiments of seed survival showed high seed predation at or near the ground surface, but fresh seeds placed 10 cm underground in the fall had 80% survival to the seedling stage after one year. Comparative behavior of seed foragers, as well as the distance and pattern of seed dispersal, implicate Cyanocitta cristata (Blue Jay) as the most likely primary dispersers and planters of the chestnut seeds.
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