We have a small tree in the yard that produced fruit each year but we had no idea what it was. Last year it was finally revealed that it is a medlar. Related to the pear and quince, it is cold and frost tolerant ( I guess that is why it has survived here). The fruit is picked in early winter, after a frost, and left to ripen. Ripening involves waiting until the fruit begins to rot - this is know as bletting one's medlars. Once the medlar has reached this stage it is ready to cook into beautiful medlar jelly. The flavour is described as very dry grated apple, with finely chopped dates added, and a dry red wine to add an astringent tinge. Medlar Jelly Recipe