This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
(ancient Greek name, derived from kratos, strength, on account of the hardiness of the wood). Rosaceae, subfamily 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: leaves alternate, deciduous, stipulate, serrate, often lobed or pinnatifid: flowers white, in some varieties red, in corymbs, rarely solitary; petals and calyx-lobes 5; stamens 5-25, usually 10 or 20; styles 1-5: fruit 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 Speci-erum Generis Cratsegi" (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. Oxyacantha and C monogyna. Most of the species have very decorative fruit which in C. Phaenopyrum, C. nitida, C. viridis, C.
C. pruinosa, C. Carrierei, C. persistans, 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. sanguined 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. intricata, 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.
Fig. 1096. Thorns of Crataegus. They are modified branches, being in the axils of leaves; sometimes, as in the lower figure, some of the short branches bear leaves.
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, and 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 Tomentosae groups germinate abundantly. The germination of the species m the Pruinosae group have a much lower percentage than in the former. The species in the Intri-catae group germinate badly.
Fig. 1097. Pomes of Crataegus, one of the large-fruited forms. (Half size.)