Malus

From Wikipedia, the free encyclopedia

This article is about the genus Malus. For other uses, see Malus (disambiguation).
iMalus - Apples and Crabapples
Malus sargentii flowers
Malus sargentii flowers
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Rosales
Family: Rosaceae
Subfamily: Maloideae
Genus: Malus
Tourn. ex L.
Species

Malus angustifolia - Southern Crab
Malus baccata - Siberian Crabapple
Malus bracteata
Malus brevipes
Malus coronaria - Sweet Crabapple
Malus domestica - Apple
Malus florentina
Malus floribunda - Japanese Crabapple
Malus formosana
Malus fusca - Oregon Crab, Pacific Crab
Malus glabrata
Malus glaucescens
Malus halliana
Malus honanensis
Malus hupehensis - Chinese Crabapple
Malus ioensis - Prairie Crab
Malus kansuensis
Malus lancifolia
Malus prattii
Malus prunifolia
Malus pumila
Malus rockii
Malus sargentii
Malus sieboldii
Malus sieversii - Asian Wild Apple
Malus sikkimensis
Malus spectabilis
Malus sublobata
Malus sylvestris - European Wild Apple
Malus toringoides
Malus transitoria
Malus trilobata
Malus tschonoskii
Malus yunnanensis

Malus, the apples, is a genus of about 30-35 species of small deciduous trees or shrubs in the family Rosaceae, including the domesticated Orchard or Table Apple (M. domestica, derived from M. sieversii, syn. M. pumila). The other species are generally known as "wild apples", "crab apples", "crabapples" or "crabs", this name being derived from their small and tart fruit. Many consider these apples unpalatable, but others enjoy eating them raw or using them for cooking or juicing. The genus is native to the temperate zone of the Northern Hemisphere, in Europe, Asia and North America.

Malus sikkimensis fruit
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Malus sikkimensis fruit

Apple trees are small, typically 4-12 m tall at maturity, with a dense, twiggy crown. The leaves are 3-10 cm long, alternate, simple, with a serrated margin. The flowers are borne in corymbs, and have five petals, which may be white, pink or red, and are perfect, with usually red stamens that produce copious pollen, and an inferior ovary; flowering occurs in the spring after 50-80 growing degree days. Apples require cross-pollination between individuals by insects (typically bees, which freely visit the flowers for both nectar and pollen); all are self-sterile, and self-pollination is impossible making pollinating insects essential. The honeybee is the most effective pollinator of apples. Malus species, including domestic apples, hybridise freely. Malus species are used as food plants by the larvae of a large number of Lepidoptera species; see list of Lepidoptera which feed on Malus.

Crabapple fruit are mostly red, but some, such as this cultivar 'Golden Hornet', are yellow
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Crabapple fruit are mostly red, but some, such as this cultivar 'Golden Hornet', are yellow

The fruit is a globose pome, varying in size from 1-4 cm diameter in most of the wild species, to 6 cm in M. pumila, 8 cm in M. sieversii, and even larger in cultivated orchard apples. The centre of the fruit contains five carpels arranged star-like, each containing one to two (rarely three) seeds.

One species, Malus trilobata from southwest Asia, has three- to seven- lobed leaves (superficially resembling a maple leaf) and with several structural differences in the fruit; it is often treated in a genus of its own, as Eriolobus trilobatus.

[edit] Uses

Ripe crabapple fruit
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Ripe crabapple fruit

For Malus domestica, see Apple. The fruit of the other species is not an important crop, being extremely sour and (in some species) woody, and is rarely eaten raw for this reason. However, crabapples are extra rich in pectin, and their juice can be made into a ruby-coloured jelly with a full, spicy flavour[1]. A small percentage of crab apples in cider makes a more interesting flavour.

Crabapples are widely grown as ornamental trees, grown for their beautiful flowers or fruit, with numerous cultivars selected for these qualities and for resistance to disease.

Some crab apples are used as rootstocks for domestic apples to add beneficial characteristics. For example, Siberian crab rootstock is often used to give additional cold hardiness to the combined plant for orchards in cold northern areas.

They are also used as pollenizers in apple orchards. Varieties of crab apple are selected to bloom contemporaneously with the apple variety in an orchard planting, and the crabs are planted every sixth or seventh tree, or limbs of crab are grafted onto some of the apple trees. In emergencies a bucket or drum bouquet of crab apple flowering branches are placed near the beehives as orchard pollenizers. See also Fruit tree pollination.

[edit] References

  1. ^ Rombauer, I., Becker, M. R., & Becker, E. [2002]. All About Canning & Preserving (The Joy of Cooking series). New York: Scribner, p. 72. ISBN 0743215028.
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