This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
A genus with half a dozen species of ornamental Ferns having large twice-pinnate fronds, and linear sori sunk in the cavities of the fronds in single rows parallel with and contiguous to the midribs of the pinnae and pinnules. The plants are hardy in the mildest parts of the kingdom, but require greenhouse protection in other places. W. areolata has fronds 6 to 12 in. long; and W. virginica about 6 in. longer, both kinds from North America. W. japonica, with fronds 1 to 2 ft. long, and W. orientalis, with fronds 4 to 8 ft. long, come from China and Japan. The best-known kind, however, is W. radicans, from the northern subtropics. It has graceful fronds 3 to 6 ft. long and 1 to 1½ ft. broad, divided into lance-shaped pinnae each of which is cut down almost to the midrib into finely toothed pinnules. The variety cristata is beautifully and symmetrically crested.