Pickled walnuts used in recipes, commonly cooked in beef dishes. Pickled walnuts are made from the fruit of both common walnut tree varieties: "Juglans regia", the Persian, royal, English or common walnut, and "Juglans nigra", the black or American walnut. The first stage is to pick the walnuts whilst they are still green and before the shells have set. Most recipes say that late June is about the best time to pick them. The soft walnuts are then soaked in brine (salt water) for at least ten days. The walnuts are then drained and left to dry in the air. Soaking the
Australian green tree frog by the preservative and appeared blue. The color of the frog is caused by blue and green pigments covered in a yellow layer; the preservative destroyed the yellow layer and left the frog with a blue appearance. The specific epithet, "caerulea", which is Latin for blue, has remained. This frog is sometimes referred to as "Pelodryas caerulea" in the scientific literature. In Australia, the frog is also known more simply as the "green tree frog", but that name is often given to the most common green arboreal species in a region, such as the American green tree frog ("Hyla cinerea").