A worldwide community photographing and learning about wildlife
Pyrus calleryana
Plant: 30-50 ft. tall, 20-30 ft. wide; young trees may be thorny. Leaves: deciduous, alternate, simple, broad-ovate to ovate, 1½-3 in. long; shiny dark green and leathery, small round-toothed margins; scarlet, mahogany, purple hues in fall. Flowers, fruits and seeds: flowers in early spring before the leaves, white with five petals, about 1 in. across; fruits mature in fall and are small, hard, brown, and almost woody. Spreads: by seeds that are dispersed to new locations by starlings and other birds that eat the fruits.
Callery pears have escaped from yards and established themselves, quite thickly in some areas, along the shoreline of this part of Lake Lewisville.
Ecological Threat Once established Callery pear forms dense thickets that push out other plants including native species that can’t tolerate the deep shade or compete with pear for water, soil and space. A single tree can spread rapidly by seed and vegetative means forming a sizeable patch within several years. Its success as an invader results from its capacity to produce copious amounts of seed that is dispersed by birds and possibly small mammals, seedlings that germinate and grow rapidly in disturbed areas and a general lack of natural controls like insects and diseases, with the exception of fire blight.
No Comments