Sea buckthorn, I recalled from an article handed me several years ago, favors less hospitable climates in Europe and Central Asia. Russian immigrants, who prized its berries, introduced the shrubby plant to North America early in the 20th century. I'd filed away the name but kept my eyes open, until my watchfulness was finally rewarded with a jar labeled "sea-bucthorn rubbed with sugar" (370 g., $3.99), from Azerbaijan.
What I hadn't recalled from the article is that the beadlike berries of the sea buckthorn are invariably yellow-orange. The green fruit pictured on the label is another species entirely: the pineapple guava, also called guavasteen or (notes the label, in small type) feijoa. It thrives best in areas too cool for the common guava. In this preparation, which resembles a green-olive tapenade, the flavor of the feijoa does evoke the tropics, or at least the subtropics: a little guava sourness, a hint of pineapple acidity.
As for the other, I welcome any leads on local sea buckthorn.
Taley Chocolate (also known as Leila's Family)
1819 King's Highway (East 18th-East 19th Sts.), Sheepshead Bay, Brooklyn