Crataegus

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Read about Crataegus in the Standard Cyclopedia of Horticulture 

Crataegus (ancient Greek name, derived from kratos, strength, on account of the hardiness of the wood). Rosaceae, subfam. Pomeae. Crategus. Hawthorn. Woody plants grown for their handsome foliage, attractive flowers and decorative fruit which, in a few species, is edible, and also for their picturesque habit: very valuable for ornament.

Shrubs or small trees, usually spiny: Lvs. alternate, deciduous, stipulate, serrate, often lobed or pinnatifid: fls. white, in some varieties red, in corymbs, rarely solitary; petals and calyx-lobes 5; stamens 5-25, usually 10 or 20; styles 1-5: fr. a drupe-like pome, with 1-5 1-seeded bony stones.—A large genus, widely distributed in the temperate regions of the northern hemisphere, most abundant in N. Amer., where between 800 and 900 species have been described, while from the Old World only about 60 species are known. There exists no recent monograph of the genus; a systematic enumeration of the arborescent American species will be found in Sargent, "Manual of the Trees of North America," pp. 363-504; of the species of the southern states in Small, "Flora of the Southeastern United States," pp. 532-569; and of the species of the northeastern states in Gray's Manual, ed. 7, p. 460- 79, and in Britton and Brown, 111. Flor. (ed. 2) 2:294-321; for the species cult, in European gardens, see Lange, "Revisio Specierum Generis Crataegi" (1897), quoted below as Lange.

The hawthorns are hardy ornamental shrubs and trees, mostly of dense and low growth, with handsome foliage, turning, in most species, to a brilliant coloring in the fall. Almost all have attractive white flowers, pink or crimson in some varieties of C. Oxpacantha and C. monogyna. Most of the species have very decorative  fruit which in C. Phaenopyrum, C. nitida, C. viridis, C. fecunda, C. pruinosa, C. Carrierei, C. persistens, C. Oxyacantha, C. monogyna and others persist on the trees until late into the winter, while some species, as C. Arnoldiana, ripen their large fruits, which soon drop, in August; also C. dahurica, C. sanguinea and the black- fruited C. nigra ripen about the same time, and C. submollis only a little later, but the earliest of all is the southern C. aestivalis, which ripens its fruits in May. This and the blue-fruited C. brachyacantha are among the most decorative hawthorns for the southern states. The fruit of C. aestivalis, and that of C. mexicana is made into preserves and jellies; also the fruits of the Molles group are suited for jelly-making, and in South Carolina an excellent jelly similar in quality and taste to Guava jelly is made from the fruits of some species of the Flavae group. In Europe, C, monogyna and C. Oxyacantha are counted among the best hedge plants; also many American species like C. Phaenopyrum, C. Crus-galli and possibly] C. macracantha, C. intricate, C. pastorum, C. rotundifolia, may be used for hedges, but they are stronger growers and cannot be pruned so closely as the European species. The hawthorns grow well in exposed positions and as a rule do not like much shade; they are not particular as to the soil, but grow best in limestone soil, also in a rich, loamy, somewhat moist one, and even in strong clay. Propagated by seeds, sown in fall or stratified; before stratifying, most of the pulp may be removed by laying the fruits in shallow piles and allowing them to decay. Then they are mixed with sand or sifted soil and buried in the ground or kept in boxes in a cool cellar. The young plants should not be allowed to remain over one year in the seed-beds, as they form long tap-roots and are then difficult to transplant. Varieties and rarer kinds are easily budded or grafted on seedling stock of C. Oxyacantha, or other common strong-growing species. 

The spines of crategus are modified branches (see Fig. 1096). The fruits are pomes (Fig. 1097), with structure similar to that of the apple. Alfred Rehder.

The American hawthorns are highly ornamental subjects for the planting of parks and private estates. The showy flowers in spring and early summer, the conspicuous red, crimson, anal scarlet fruits of nearly all of them, which extend amongst the different species from August to early winter and midwinter,—and some of the species markedly retain their fruits without shrinkage of pulp or loss of color until early winter,— the absolute hardihood, and the bold rugged branching habits characteristic to most of them, make them very interesting objects when their leafless forms are outlined in a winter landscape. The landscape gardener cannot make any mistake in planting them in liberal quantities in private estates or public parks.

They are easily transplanted. They are much benefited by liberal pruning when transplanted from nursery rows or from the woodland. The side branches should be pruned in severely, and as the centers of good-sized plants are likely to be full of intricate and congested branches, these should be carefully thinned. In a young state they should be grown to one stem whether they are arborescent or shrubby species. Under this treatment they make beautiful garden plants.

The American hawthorns are almost invariably found growing in heavy limestone clay. They may occasionally overlap into sandy soil. In planting them in sandy soil, it should be liberally enriched with well rotted manure, and they should be kept well mulched.

The seeds of all of the species of American hawthorns germinate slowly. None of the species germinates before the second year after sowing, and many of the seeds in the same "flat" will not germinate before the third year. In many instances, part of the seeds germinate the second year, and the remainder the third. The seeds of Crataegus geneseensis have been known to be dormant for three years, and all come up thickly at the same time. In some of the groups the seeds of the species germinate more freely than in others. The species in the Molles, Flabellatae and Tomentosse groups germinate abundantly. The germination of the species in the Pruinosae group have a much lower percentage than in the former. The species in the Intricatae group germinate badly.

The fruit can be sown broadcast in beds without any separation of the seeds, and heavily mulched until the spring of the second year, when the mulching should be removed. This method, however, is not considered good, and has been given up. The best way is to soak the fruits in water, and by maceration the seeds or nutlets are separated from the pulp, and the seeds will sink to the bottom of the tub or vessel. The seeds are Chen dried in the sun as they can then be handled easily. They are sown in "flats" of convenient size to handle, and piled up in the corner of the shade house and fitted tightly above each other to prevent mice getting at them. During this period of rest they must not be allowed to become dry. In the spring of the second year they are spread out to allow the seeds to germinate. Numbered zinc tags are nailed on the flats" and the corresponding numbers with the names of the species are recorded.

The American hawthorns can be grafted readily on potted seedling stocks in the greenhouse in winter, any of the species in the Crus-galli group being good to use. They are grafted at the crown. This, however, is an unnecessary operation. All of the species of American hawthorns (and there are over 900 of them) come absolutely true from seed, and whilst they germinate slowly, they start to grow rapidly into plants of good stocky size from about two years after they germinate.

Some of the species of American hawthorns have highly colored foliage in the fall. The species in the Pruinosue, Medioximae and Intricate groups have perhaps the most highly colored foliage. Notable examples are Crataegus opulens, C. diffusa, C. maineana, C. dissona, C. cognata, C. conspecta, C. promissa, C. exornata, C. perjucunda, C. foetida, and C. verecunda.

The different species vary greatly in the time of ripening their fruits and in the period of duration. In many instances the fruit drops soon after ripening and in others hangs on for a long period. A selection of twenty-six species that would give a good fruit display from August until early or mid-winter, would be as follows: Crataegus matura, C. praecox, C. Arnoldiana, C. Dayana, C. Robesoniana, C. pedicellata, C. gloriosa, C. Ellwangeriana, C. lauta, C. submollis, C. champlainensis, C. arkansana, C. Dunbari, C. ferentaria, C. opulens, C. compta, C. gemmosa, C. livoniana, C. geneseensis, C. persimilis, C. maineana, C. Barryana, C. coccinioides, C. leiophylla, C. durobrivensis, and C. cordata. (See pp. 887-889 for some of these.) John Dunbar.


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Crataegus
Common Hawthorn (Crataegus monogyna)
Common Hawthorn (Crataegus monogyna)
Plant Info
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Rosales
Family: Rosaceae
Subfamily: Maloideae
Genus: Crataegus
Tourn. ex L.

Species
See text

Crataegus (Hawthorn) is a large genus of shrubs and trees in the family Rosaceae, native to temperate regions of the Northern Hemisphere in Europe, Asia 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. However the name is now also applied to the entire genus, and also to the related Asian genus Rhaphiolepis.

Common Hawthorn (close up of flowers)

They are shrubs and small trees growing to 5-15 m tall, characterized by their small pome fruit and thorny branches. The bark is smooth grey in young individuals, developing shallow longitudinal fissures with narrow ridges in older trees. The fruits are sometimes known as "haws", from which the name derived. The thorns grow from branches, and are typically 1-3 cm long. The leaves grow spirally arranged on long shoots, and in clusters on spur shoots on the branches or twigs. The leaves themselves have lobed or serrate margins and are somewhat variable shape.

The number of species in the genus depends on taxonomic interpretation, with numerous apomictic microspecies; some botanists recognise a thousand or more species, while others reduce the number to 200 or fewer.

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 — see list of Lepidoptera which feed on Hawthorns.

Many species and hybrids are used as ornamental and street trees. The Common Hawthorn is extensively used in Europe as a hedge plant. Several cultivars of the Midland Hawthorn C. laevigata have been selected for their pink or red flowers. Hawthorns are among the trees most recommended for water-conservation landscapes.

Selected species

Uses

Culinary use

The fruits of the species Crataegus pinnatifida (Chinese Hawthorn) are tart, bright red, and resemble small crabapple fruits. They are used to make many kinds of Chinese snacks, including haw flakes and tanghulu (糖葫芦). The fruits, which are called shānzhā () in Chinese, are also used to produce jams, jellies, juices, alcoholic beverages, and other drinks [1]. In South Korea, a liquor called sansachun (산사춘) is made from the fruits.[2]

The fruits of Crataegus pubescens are known in Mexico as tejocotes and are eaten raw, cooked, or in jam during the winter months. They are stuffed in the piñatas broken during the traditional pre-Christmas parties known as 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.

In the southern United States fruits of three native species are collectively known as Mayhaws and are made into jellies which are considered a great delicacy.

The leaves are edible and, if picked in the months of April and May, they are tender enough to be used in salads.[1]

Medicinal use

The dried fruits of Crataegus pinnatifida (called or shān zhā in Chinese) are used in naturopathic medicine and traditional Chinese medicine, primarily as a digestive aid. A closely related species, Crataegus cuneata (Japanese Hawthorn, called sanzashi in Japanese) is used in a similar manner. Other species (especially Crataegus laevigata) are used in Western herbal medicine, where the plant is believed to strengthen cardiovascular function [3]. In recent years, this use has been noted and adopted by Chinese herbalists as well [4]. Hawthorn is also used as an aid to lower blood pressure, and treat some heart related diseases.

Clinical trials

Several clinical trials have assessed the ability of hawthorn to help improve exercise tolerance in people with NYHA class II cardiac insufficiency compared to placebo. One trial, at (300mg/day) for 4 to 8 weeks, found not difference from placebo. The second trial, including 78 subjects (600mg/day) for 8 weeks, found "significant improvement in exercise tolerance" and lower blood pressure and heart rate during exercise. The third trial, including 32 subjects (900mg/day) for 8 weeks, found improved exercise tolerance as well as a reduction in the "incidence and severity of symptoms such as dyspnea and fatigue decreased by approximately 50%" [2].

In the HERB-CHF (Hawthorn Extract Randomized Blinded Chronic HF Study) clinical trial, 120 patients took 450mg of hawthorn extract twice daily for 6 months in combination with standard therapy and a standardized exercise program. "No effects of hawthorn were seen on either quality-of-life endpoint (Tables 1 and 2), or when adjusted for LVEF" [3].

One study, consisting of 1011 patients taking one tablet (standardized to 84.3mg procyanidin) twice daily for 24 weeks, found "improvements in clinical symptoms (such as fatigue, palpitations, and exercise dyspnea), performance and exercise tolerance test, and ejection fraction" [4].

Other uses

The wood of some hawthorn species is very hard and resistant to rot. In rural North America it was prized for use as tool handles and fence posts.

Folklore

The custom of employing the flowering branches for decorative purposes on the 1st of May is of very early origin; but since the adoption of the Gregorian calendar in 1752, the tree has rarely been in full bloom in England before the second week of that month. In the Scottish Highlands the flowers may be seen as late as the middle of June. The hawthorn has been regarded as the emblem of hope, and its branches are stated to have been carried by the ancient Greeks in wedding processions, and to have been used by them to deck the altar of Hymenaios. The supposition that the tree was the source of Jesus's crown of thorns gave rise doubtless to the tradition current among the French peasantry that it utters groans and cries on Good Friday, and probably also to the old popular superstition in Great Britain and Ireland that ill-luck attended the uprooting of hawthorns. Branches of Glastonbury Thorn, C. Oxyacantha, var. praecox, which flowers both in December and in spring, were formerly highly valued in England, on account of the legend that the tree was originally the staff of Joseph of Arimathea.[5]

In Celtic lore, the hawthorn plant was used commonly for rune inscriptions along with Yew and Apple. It was once said to heal the broken heart.

References and external links

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  1. Richard Mabey, Food for Free, Collins, October 2001.
  2. Bauman HHSFJL (2002). Hawthorn. Journal of Cardiovascular Nursing 16:1-8
  3. Aaronson K: HERB-CHF: Hawthorn Extract Randomized Blinded Chronic Heart Failure Trial. In, 2004
  4. Sweet JMRBV (2002). Hawthorn: Pharmacology and therapeutic uses. American Journal of Health-System Pharmacy 59: 417-422
  5. "Hawthorn" article in the 1911 Encyclopedia