Crataegus


Crataegus, commonly called hawthorn, quickthorn, thornapple, May-tree, whitethorn, Mayflower or hawberry, is a genus of several hundred species of shrubs and trees in the family Rosaceae, native to temperate regions of the Northern Hemisphere in Europe, Asia, North Africa and North America. The name "hawthorn" was originally applied to the species native to northern Europe, especially the common hawthorn C. monogyna, and the unmodified name is often so used in Britain and Ireland. The name is now also applied to the entire genus and to the related Asian genus Rhaphiolepis.

Description

Crataegus species are shrubs or small trees, mostly growing to tall, with small fruit and thorny branches. The most common type of bark is smooth grey in young individuals, developing shallow longitudinal fissures with narrow ridges in older trees. The thorns are sharp-tipped branches that arise either from other branches or from the trunk, and are typically long. The leaves grow spirally arranged on long shoots, and in clusters on spur shoots on the branches or twigs. The leaves of most species have lobed or serrated margins and are somewhat variable in shape. Flowers are five-petalled and grow in flat-topped clusters and are most typically white, although they can also be pale pink or occasionally scarlet in colour. The fruit, sometimes known as a "haw", appears berry-like but is structurally polypyrenous, with from one to five pyrenes that resemble the "stones" of plums, peaches, etc., which are drupaceous fruit in the same subfamily.

Taxonomy

The number of species in the genus depends on taxonomic interpretation. Some botanists in the past recognised 1000 or more species, many of which are apomictic microspecies. A reasonable number is estimated to be 200 species. The genus likely first appeared in the Eocene, with the ancestral area likely being Eastern North America and in Europe, which at that time remained closely linked due to the North Atlantic Land Bridge. The earliest known leaves of the genus from the Eocene of North America, with the earliest leaves from Europe being from the Oligocene.
The genus is classified into sections which are further divided into series. Series Montaninsulae has not yet been assigned to a section. The sections are:
  • section Brevispinae
  • section Crataegus
  • section Coccineae
  • section Cuneatae
  • section Douglasia
  • section Hupehensis
  • section Macracanthae
  • section ''Sanguineae''

    Selected species

  • Crataegus aemula – Rome hawthorn
  • Crataegus aestivalis – May hawthorn
  • Crataegus alabamensis – Alabama hawthorn
  • Crataegus altaica – Altai hawthorn
  • Crataegus ambigua – Russian hawthorn
  • Crataegus ambitiosa – Grand Rapids hawthorn
  • Crataegus anamesa – Fort Bend hawthorn
  • Crataegus ancisa – Mississippi hawthorn
  • Crataegus annosa – Phoenix City hawthorn
  • Crataegus aprica – sunny hawthorn
  • Crataegus arborea – Montgomery hawthorn
  • Crataegus arcana – Carolina hawthorn
  • Crataegus ater – Nashville hawthorn
  • Crataegus austromontana – valley head hawthorn
  • Crataegus azarolus – Azarole hawthorn
  • Crataegus berberifolia – barberry hawthorn
  • Crataegus biltmoreana – Biltmore hawthorn
  • Crataegus boyntonii – stinking hawthorn
  • Crataegus brachyacantha – blueberry hawthorn
  • Crataegus brainerdii – Brainerd's hawthorn
  • Crataegus calpodendron – late hawthorn
  • Crataegus canbyi
  • Crataegus chlorosarca
  • Crataegus chrysocarpa – fireberry hawthorn
  • Crataegus coccinea – scarlet hawthorn
  • Crataegus coccinioides – Kansas hawthorn
  • Crataegus collina – hillside hawthorn
  • Crataegus crus-galli – cockspur hawthorn
  • Crataegus cuneata – Japanese hawthorn
  • Crataegus cupulifera
  • Crataegus dahurica
  • Crataegus dilatata – broadleaf hawthorn, Apple-leaf hawthorn
  • Crataegus douglasii – black hawthorn, Douglas hawthorn
  • Crataegus ellwangeriana
  • Crataegus erythropoda – cerro hawthorn
  • Crataegus flabellata – Gray's hawthorn, fanleaf hawthorn
  • Crataegus flava – yellow-fruited hawthorn
  • Crataegus fluviatilis
  • Crataegus fontanesiana
  • Crataegus greggiana – Gregg's hawthorn
  • Crataegus harbisonii – Harbison's hawthorn
  • Crataegus heldreichii
  • Crataegus heterophylla – various-leaved hawthorn
  • Crataegus holmesiana – Holmes' hawthorn
  • Crataegus hupehensis
  • Crataegus intricata – thicket hawthorn, intricate hawthorn
  • Crataegus iracunda – stolon–bearing hawthorn
  • Crataegus jackii
  • Crataegus jonesae
  • Crataegus kansuensis – Gansu hawthorn
  • Crataegus laevigata – Midland hawthorn, English hawthorn
  • Crataegus lassa – sandhill hawthorn
  • Crataegus lepida
  • Crataegus macrosperma – big-fruit hawthorn
  • Crataegus marshallii – parsley-leaved hawthorn
  • Crataegus maximowiczii
  • Crataegus mercerensis
  • Crataegus mexicana – tejocote, Mexican hawthorn
  • Crataegus mollis – downy hawthorn
  • Crataegus monogyna – common hawthorn, oneseed hawthorn
  • Crataegus nigra – Hungarian hawthorn
  • Crataegus okanaganensis – Okanagan Valley hawthorn
  • Crataegus opaca – western mayhaw
  • Crataegus orientalis – oriental hawthorn
  • Crataegus pedicellata – scarlet hawthorn
  • Crataegus pennsylvanica – Pennsylvania thorn
  • Crataegus pentagyna – small-flowered black hawthorn
  • Crataegus peregrina
  • Crataegus persimilis – plumleaf hawthorn
  • Crataegus phaenopyrum – Washington hawthorn
  • Crataegus phippsii
  • Crataegus pinnatifida – Chinese hawthorn
  • Crataegus populnea – poplar hawthorn
  • Crataegus pratensis – prairie hawthorn
  • Crataegus pruinosa – frosted hawthorn
  • Crataegus pulcherrima – beautiful hawthorn
  • Crataegus punctata – dotted hawthorn, white hawthorn: sometimes claimed as the state flower of Missouri, though the legislation does not specify a species
  • Crataegus purpurella – Loch Lomond hawthorn
  • Crataegus putnamiana
  • Crataegus pycnoloba
  • Crataegus reverchonii – Reverchon's hawthorn
  • Crataegus rhipidophylla
  • Crataegus rivularis – river hawthorn
  • Crataegus saligna – willow hawthorn
  • Crataegus sanguinea – redhaw hawthorn, Siberian hawthorn
  • Crataegus sargentii – Sargent's hawthorn
  • Crataegus scabrida – rough hawthorn
  • Crataegus scabrifolia
  • Crataegus songarica
  • Crataegus spathulata – littlehip hawthorn
  • Crataegus submollis – Quebec hawthorn
  • Crataegus succulenta – fleshy hawthorn
  • Crataegus tanacetifolia – tansy–leaved thorn
  • Crataegus texana – Texas hawthorn
  • Crataegus tracyi – Tracy hawthorn
  • Crataegus triflora – three-flowered hawthorn
  • Crataegus uniflora – one-flowered hawthorn, dwarf hawthorn
  • Crataegus viridis – green hawthorn, including cultivar 'Winter King'
  • Crataegus visenda
  • Crataegus vulsa – Alabama hawthorn
  • Crataegus wattiana – Altai hawthorn
  • Crataegus wilsonii – Wilson hawthorn

    Selected hybrids

  • Crataegus × ariifolia
  • Crataegus × dsungarica
  • Crataegus × grignonensis – Grignon hawthorn, an unpublished name
  • Crataegus × lavalleei – Lavallée hawthorn, including Crataegus × carrierei
  • Crataegus × macrocarpa
  • Crataegus × media – the name for C. monogyna × C. laevigata hybrids
  • Crataegus × mordenensis – Morden hawthorn, including 'Toba' and 'Snowbird'
  • – Hybrid Hawthorn, Whithorn, Single-seed Hawthorn. Hybrid between C. azarolus and C. monogyna.
  • Crataegus × sinaica – za'rur
  • Crataegus × smithiana – red Mexican hawthorn, an unpublished name
  • Crataegus × ''vailiae''

    Graft-chimaera

Together with the genus Pyrus, it forms the graft-chimaera + Pyrocrataegus.

Etymology

The generic epithet, Crataegus, is derived from the Greek "strength" because of the great strength of the wood and "sharp", referring to the thorns of some species. The name haw, originally an Old English term for hedge, also applies to the fruit.

Ecology

Hawthorns provide food and shelter for many species of birds and mammals, and the flowers are important for many nectar-feeding insects. Hawthorns are also used as food plants by the larvae of a large number of Lepidoptera species, such as the small eggar moth, E. lanestris. Haws are important for wildlife in winter, particularly thrushes and waxwings; these birds eat the haws and disperse the seeds in their droppings.

Propagation

Although it is commonly stated that hawthorns can be propagated by cutting, this is difficult to achieve with rootless stem pieces. Small plants or suckers are often transplanted from the wild. Seeds require stratification and take one or two years to germinate. Seed germination is improved if the pyrenes that contain the seed are subjected to extensive drying at room temperature, before stratification. Uncommon forms can be grafted onto seedlings of other species.

Uses

Culinary use

The "haws" or fruits of the common hawthorn, C. monogyna, are edible. In the United Kingdom, they are sometimes used to make a jelly or homemade wine. The leaves are edible, and if picked in spring when still young, are tender enough to be used in salads. The young leaves and flower buds, which are also edible, are known as "bread and cheese" in rural England. In the southern United States, fruits of three native species, C. aestivalis, C. opaca and C. rufula, are collectively known as mayhaws and are made into conserves and pies and fermented into wine. The Kutenai people of northwestern North America used red and black hawthorn fruit for food.
On Manitoulin Island, Ontario, some red-fruited species are called hawberries. During colonisation, European settlers ate these fruits during the winter as the only remaining food supply. People born on the island are now called "haweaters".
In Mexico the fruit of many Crataegus species are known as tejocotes, but only C. mexicana appears to be cultivated for culinary use. They are stuffed in the piñatas broken during the traditional pre-Christmas celebration known as Las Posadas. They are also cooked with other fruits to prepare a Christmas punch. The mixture of tejocote paste, sugar and chili powder produces a popular Mexican candy called rielitos, which is manufactured by several brands.
The fruits of the species C. pinnatifida, and particularly the large-fruited C. pinnatifida var. major are cultivated. They are tart, bright red and resemble small crabapple fruits. They are used to make many kinds of Chinese snacks, such as tanghulu — coated in sugar syrup and skewered – and haw flakes. The fruits, which are called 山楂 shān zhā in Chinese, are also used to produce jams, jellies, juices, alcoholic beverages and other drinks; these could in turn be used in other dishes. In South Korea, a liquor called sansachun is made from the fruits.
In Iran, the fruits of Crataegus are known as zâlzâlak and eaten raw as a snack, or made into a jam known by the same name.
The fruits of North America's C. greggiana are made into preserves.