Small corymbs of white flowers are produced from short spur twigs; these corymbs span about 1½-3" across and they are rather flat-headed. The flowering stalks of the corymbs are light to reddish green and pubescent. Individual flowers are about 1" across, consisting of 5 white spreading petals, 5 green sepals that are united at the base, 20 stamens with pale yellow anthers, and an inferior ovary with 4-5 styles. Individual sepals are narrowly lanceolate in shape; they have conspicuous glandular teeth. The blooming period occurs for about 2 weeks during late spring; the flowers have an unpleasant odor. Fertile flowers are replaced by small globoid pomes (apple-like fruits) that become ¾-1" across at maturity during late summer. Young pomes are light green and pubescent, while mature pomes are yellowish red to scarlet and hairless (or nearly so). The interior of each mature pome contains firm flesh that is pale yellow and slightly juicy; it has an apple-like sweet-tart flavor. Each pome also contains 4-5 chunky seeds. The root system is woody and branching. Downy Hawthorn spreads by reseeding itself.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and fertile loamy soil. However, other kinds of soil and drier conditions are also tolerated. The leaves of Downy Hawthorn are vulnerable to several foliar diseases, including cedar-hawthorn rust, scab, and leaf blight. As a result, the leaves are often battered from disease by the end of summer and usually succumb to premature leaf-drop.
Range & Habitat: The native Downy Hawthorn is common in the northern half of Illinois, while in the southern half of the state it is occasional or absent (see Distribution Map). Habitats include openings in bottomland woodlands, mesic savannas, woodland borders, thickets, banks of rivers, and abandoned pastures. Downy Hawthorn is a pioneer species that is intolerant of the dense shade that is cast by canopy trees. It is rarely cultivated as a landscape shrub or tree.
Faunal Associations: The nectar and pollen of the flowers attract primarily small bees (Halictid & Andrenid), flies (Syrphid, Calliphorid, Muscid, etc.), and miscellaneous beetles. Other insects feed on the foliage, flowers, plant juices, or wood of Crataegus spp. (Hawthorns). These species include caterpillars of the butterfly, Satyrium liparops strigosum (Striped Hairstreak), caterpillars of the moth Catocala crataegi (Hawthorn Underwing), and several other moths (see Moth Table). Other insect feeders include Eriosoma crataegi (Woolly Hawthorn Aphid) and other aphids, Glossonotus crataegi (Quince Treehopper), Corythucha cydoniae (Hawthorn Lace Bug), Lygidea mendax (Apple Red Bug) and other plant bugs, the flea beetle Crepidodera violacea, the larvae of Saperda fayi (Thorn Limb Borer) and other long-horned beetles, and Anthonomus nebulosus (Hawthorn Blossum Weevil). Hawthorns are preferred host plants of several leafhoppers: Balcanocerus crataegi, Eratoneura minor, Erythridula bitincta, Erythridula funesta, Erythridula furcillata, Erythridula repleta, Erythridula rubens, and Erythridula spatulata. Many upland gamebirds and songbirds eat the fruit of hawthorns (see Bird Table), as do such mammals as black bears, foxes, coyotes, raccoons, skunks, and tree squirrels. White-Tailed Deer and the Cottontail Rabbit occasionally browse on the twigs and foliage. Because of their dense branching structure and thorns, Downy Hawthorn and other hawthorns provide nesting habitat for the Yellow-Breasted Chat, Brown Thrasher, and other birds. They also provide excellent protective cover for birds and other wildlife during the summer.
Photographic Location: The Arboretum at the University of Illinois in Urbana, Illinois.
Comments: Downy Hawthorn is one of the more common Crataegus spp. (hawthorns) in Illinois, particularly in the northern half of the state. It is relatively easy to recognize (for a hawthorn) because of its pubescent leaves, pubescent shoots, and pubescent immature fruits. The showy fruits of this species are among the first to mature among hawthorns, although they remain on the tree for only a short time before falling to the ground. The edible fruits have a pleasant flavor, although they are seedy. Across its range, there is some variability in the shape of the leaves and other characteristics of this small tree or shrub. As a result, many former species (Crataegus altrix, C. declivitatis, C. lanigera, C. nupera, C. pachyphylla, C. ridwayi, C. sera, C. umbrosa, C. valens, C. verna, and C. verosa) are now regarded as different forms of Crataegus mollis (Downy Hawthorn).