Pears
Most pears are deciduous, but one or two species in southeast Asia are evergreen. Most are cold-hardy, withstanding temperatures between −25 °C and −40 °C in winter, except for the evergreen species, which only tolerate temperatures down to about −15 °C. The flowers are white, rarely tinted yellow or pink, 2–4 cm diameter, and have five petals.
Like that of the related apple, the pear fruit is a pome, in most wild species 1–4 cm diameter, but in some cultivated forms up to 18 cm long and 8 cm broad; the shape varies in most species from oblate or globose, to the classic pyriform ‘pear-shape’ of the European Pear with an elongated basal portion and a bulbous end. The fruit is composed of the receptacle or upper end of the flower-stalk (the so-called calyx tube) greatly dilated. Enclosed within its cellular flesh is the true fruit: five cartilaginous carpels, known colloquially as the “core”. From the upper rim of the receptacle are given off the five sepals, the five stamens.
The pear is very similar to the apple in cultivation, propagation and pollination. The pear and the apple are also related to the quince. Summer and autumn pears are gathered before they are fully ripe, while they are still green, but snap off when lifted. If left to ripen and turn yellow on the tree, the sugars will turn to starch crystals and the pear will have a gritty texture inside. In the case of the ‘Passe Crassane’, long the favored winter pear in France, the crop should be gathered at three different times, the first a fortnight or more before it is ripe, the second a week or ten days after that, and the third when fully ripe.The first gathering will come into eating last, and thus the season of the fruit may be considerably prolonged.
Pears are consumed fresh, canned, as juice, and dried. The juice can also be used in jellies and jams, usually in combination with other fruits or berries. Fermented pear juice is called perry or pear cider. Pears ripen at room temperature. They will ripen faster if placed next to bananas in a fruit bowl. Refrigerate pears to slow further ripening. Pears are an excellent source of dietary fiber and a good source of Vitamin C.
For more information:
http://en.wikipedia.org/wiki/Pear_tree
http://www.saskfruit.com/studentwebsites/Pear%20Ingram/pears_on_the_prairies.htm