The Crab Apple Malus sylvestris is native to Europe, including Britain, Western Russia and Turkey. Its scientific name means ‘forest apple’. It is often found in old woods and hedgerows. It is the ‘wild’ apple of Europe but can easily be confused with Orchard Apple trees (Malus domestica) that have grown from the pips of discarded apples. Crab Apple leaves are hairless underneath, whereas the Orchard Apple leaves are hairy. In most years, from summer onwards, crab apples are easy to see and can identify the tree. They are small, yellow, hard and acid to the taste. In winter they can often be found under the tree. The tree may have thorns on lower branches.
The Orchard Apple Malus domestica, sometimes called the Cultivated Apple, is believed to have originated from a wild species (Malus seversii) that grows in central Asia. Cultivation began more than 2000 years ago. The original ancestor has been improved through selection and cross breeding so that there are now more than 7000 varieties worldwide. There are apples suitable for eating, cooking or even making cider. The National Fruit Collection at Brogdale, Kent lists more than 2200 varieties of apples in its database.
Apples have 34 chromosomes so when pollinated they get 17 from one parent and 17 from another. In Nottingham in the 19th century a single seed generated a tree with apples of a superb taste – a Bramley. Apples are genetically extremely heterozygous and so do not breed true. So if you plant the seed of a Bramley you will not get another Bramley. To propagate the new tree you need to take a cutting (scion) and graft it onto a suitable rootstock e.g the M9. So all the Bramleys are from one tree in Nottingham which was grown from a single seed in about 1810! The technique of grafting has been known since ancient times, in China from 2000BC. The rootstock and the scion retain their own genes so effectively each new tree is a clone.
Crab Apple Tree in blossom at the end of April.
This is the leaf of a Crab Apple. It has small teeth. The underside of the mature leaf of the Crab Apple is hairless. The underside of the Orchard Apple leaf is covered in fine white hairs.
A flower in early May. Each flower has 5 white, pink-tinged petals, 15 to 20 yellow anthers and up to 5 green styles/stigmas. In comparison, the anthers of the Common Pear are deep red. This close-up shows the 5 green stigmas between the yellow anthers.
The ovary is located below the petals. After pollination the ovary, including its seeds, develops into a fruit which reaches this size in early June.
Crab Apples are small, hard and acidic to the taste. The fruit is known as a pome by botanists.
Orchard apples. Photo taken in September.