There are no active references in this article.
The species whose descriptions are given below have been by various authors placed in Cotoneaster, Mespilus, and Crataegus. They are, no doubt, most closely allied to the last, differing chiefly in having leafy thorns, in being evergreen, and in the leaves being either entire or merely toothed, never lobed. There are also differences in the ovules. From Cotoneaster they are equally distinct in having thorny branches and toothed leaves. For the rest they may be described as evergreen shrubs with alternate leaves and white flowers; stamens about twenty; styles five. Fruits globose or orange-shaped, yellow, or scarlet. They are easily satisfied as regards soil, thriving in any that is warm and not very heavy. All the pyracanths are hardy in the open ground (except perhaps the uncommon P. angustifolia, P. crenulata, and P. koidzumii) and will flower and bear fruits freely there. But few evergreen shrubs are better for furnishing a house-wall, and their fruits are safer there from the depredations of birds, especially in quiet country gardens. P. coccinea is one of the commonest of wall-shrubs but there are other species and hybrids which are just as fine and probably more resistant to scab. Open-ground plants need no regular pruning and should not be cut more than is absolutely necessary to restrict size. For plants grown close against a wall, careful training and tying-in of the branches is more important than pruning, but the season’s growths may be shortened after flowering.
Many of the pyracanths are subject to attack by scab, which forms a sooty coating of spores on the foliage and fruits and causes the foliage to wither and fall prematurely; die-back may also occur. The recommended treatment is to spray with captan three times in March and April and twice in June. It is claimed for some of the modern hybrids that they are scab-resistant, but only trial could confirm this. The pyracanths are also susceptible to Fireblight (see Vol. I, p. 730, and Dictionary of Gardening, Supplement (1969), p. 307).