LILAC, 1 or PIPE TREE (Syringa mlgaris) , a tree of the olive family, Oleaceae. The genus contains about ten species of ornamental hardy deciduous shrubs native in eastern Europe and temperate Asia. They have opposite, generally entire leaves and large panicles of small regular flowers, with a bell-shaped calyx and a 4-lobed cylindrical corolla, with the two stamens characteristic of the order attached at the mouth of the tube. The common lilac is said to have come from Persia in the 16th century, but is doubtfully indigenous in Hungary, the borders of Moldavia, etc. Two kinds of Syringa, viz. alba and caerulea, are figured and described by Gerard (Herball, 1597), which he calls the white and the blue pipe privets. The former is the common privet, Ligustrum vulgar e, which, and the ash tree, Fraxinus excelsior, are the only members of the family native in Great Britain. The latter is the lilac, as both figure and description agree accurately with it. It was carried by the European colonists to north-east America, and is still grown in gardens of the northern and middle states.
There are many fine varieties of lilac, both with single and double flowers: they are among the commonest and most beautiful of spring-flowering shrubs. The so-called Persian lilac of gardens (S. dubia, S. chinensis var. Rothomagensis), also known as the Chinese or Rouen lilac, a small shrub 4 to 6 ft. high with intense violet flowers appearing in May and June, is considered to be a hybrid between S. vulgaris and 5. persica the true Persian lilac, a native of Persia and Afghanistan, a shrub 4 to 7 ft. high with bluish-purpje or white flowers. Of other species, S. Josikaea, from Transylvania, has scentless bluish-purple flowers; S. Emodi, a native of the Himalayas, is a handsome shrub with large ovate leaves and dense panicles of purple or white strongly scented flowers. Lilacs grow freely and flower profusely in almost any soil and situation, but when neglected are apt to become choked with suckers which shoot up in great numbers from the base. They are readily propagated by means of these suckers.
Syringa is also a common name for the mock-orange Philadelphus coronarius (nat. ord. Saxifragaceae), a handsome shrub 2 to 10 ft. high, with smooth ovate leaves and clusters of white flowers which have a strong orange-like scent. It is a native of western Asia, and perhaps some parts of southern Europe.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)