"A tree may be valued for what it is, but a shrub is rated for just what it can do. It must render a service to compensate for its cultivation. This service may be one of beauty, through its flowers; or of use, by its fruit; or its foliage or habit of growth may be especially attractive, or of such a nature as will give it value as a shield or a cover for waste and barren places"
—Harriet Keeler, author and amateur botanist
Our Native Trees and How to Identify Them, 1900