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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.
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