Red, yellow, green, or some combination thereof, with a greenish or yellowish white flesh, apples are one of the world's most widely cultivated fruits. All of the 30-35 species belonging to the genus malus are properly termed apples, but all table apples belong to a single species, malus domestica, of which there are approximately 10,000 known cultivars. The other species are often known as crabapples.
Apples are classified as one of the pome (fleshy) fruits, in which the ripened ovary and surrounding tissue both become fleshy and edible. Apple varieties range in flavor from very tart to very sweet, with different cultures favoring different flavors. Americans generally favor mildly tart to mildly sweet apples, while Asian peoples generally favor very sweet or very mild flavors, and some European cultures favor very tart flavors.
Table apples have a wide variety of uses. About 50 percent of the world apple crop is eaten as fresh fruit, but apples are also used to make juice, cider, jelly, jam, apple butter, applesauce, and hard liquors such as Applejack. Apples are commonly found as fillings in desserts such as pies, tarts, cobblers, crisps, crumble cakes, danishes, and strudels. In addition, scraps from apple processing are often used to make vinegar and pectin.
Apples are often touted for their health benefits, as in the proverb, "An apple a day keeps the doctor away." Apples do indeed provide great nutritional value, serving as an excellent source of vitamins A and C and dietary fiber. Studies have shown that eating apples often can reduce the risk of heart disease and many types of cancers, and also helps control cholesterol levels.
Crabapples are only rarely eaten due to their extreme acidity, but make excellent jellies and tarts, and are sometimes cultivated for the beauty of their blossoms. The wood of most apple trees is useful for making tasteful hardwood furniture, and also makes serviceable firewood.
History and Culture
Apparently native to the Caucasus region of western Asia, apples may well have been the earliest tree fruit to be domesticated, and has been in constant cultivation since prehistoric times. Because they store well, apples have long been an important winter fruit in Europe and Asia, and are mentioned in many of the earliest known myths of humanity, including the Bible and Homer. Different varieties of apples were already being bred by the Greeks more than 2,000 years ago, and by the 1400s several hundreds of varieties were already known in Europe. Apples were brought to north America with the European settlement of the New World and quickly found an ideal growing climate in the temperate zones of what is now the northern United States and southern Canada. In recent years, apples have also been found to flourish particularly well in New Zealand.
Apples have served as an important cultural symbol and mythic element in many societies. In Genesis 3, the forbidden fruit from the Tree of Life eaten by Adam and Eve was an apple, as was the Apple of Discord, inscribed by the goddess Eris with the word Kallisti ("To the fairest"), which brought about the Trojan War in Homer's Illiad. One of the Twelve Labors of Hercules was to find the golden apples of the Hesperides. In Norse mythology, Idun was the keeper of "apples of immortality" which kept the gods of Valhalla forever young. In later years, Swiss patriot William Tell famously shot an apple off the head of his young son with a crossbow, and Isaac Newton is alleged to have discovered gravity when an apple fell on his head. In the America, apple pie is a favorite dish, leading to the saying "As American as apple pie" and Johnny Appleseed is a celebrated folk hero for planting apple seedlings across Ohio and Indiana.
Apples are associated with numerous symbolic meanings, including love, lust, sin, fertility, sexuality, knowledge, health, and peace. For example, apples are eaten on the Jewish new year of Rosh Hashanah to symbolize a sweet new year. Danish folklore says that apples wither around adulterers. Eating apples is often said to help increase a woman's chances of conception or remove blemishes from the skin. Displaying apple branches above one's door or in one's home is said to insure peace and health and ward off evil. In the United States, the apple is a traditional gift for a teacher.
Apples require a period of dormancy, and thus grow best in regions with a distinct winter, usually in areas between 30° and 60° latitude, either north or south. Apple orchards are best placed on the tops of rolling hills. This allows cool air and moisture to sink away from the trees on cold winter nights, preventing the blossoms or young fruits from being destroyed by frost.
Pollen management is an important aspect of apple orchard design, as apples cannot self-pollinate and must rely on cross pollination. Some apple varieties do not produce enough pollen, and must be interspersed with other varieties that generate high pollen yields. Apple trees are especially reliant upon insect pollinators, and bees may need to be brought in during pollination season if local bees prove insufficient.
Apples are difficult to grow organically, because they are susceptible to numerous pests and diseases, including fungal menaces such as Gymnosporangium rust, apple scab, and black spot, the bacterial disease fireblight, and insect pests such as the plum curlico, the apple maggot, and the codling moth. In recent years however, some organic farms have had success growing especially disease and pest resistant cultivars.
Breeding new apple trees is challenging, but also fun and interesting, often involving luck or chance. The vast majority of new trees are produced by grafting, with the occasional tree produced by budding. Budding is especially interesting because it sometimes produces apples quite different from the parent tree. It is comparatively difficult to grow apple trees from seeds, although this sometimes happens by accident. Most new varieties of apples are produced from seedlings, many of which were found by chance. Recently, efforts to crossbreed malus domestica with other apple species has increased the promise of developing hardy new species resistant to disease or able to be grown in warmer climes.