This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Although really forms of Cupressus, the Retinosporas are so distinct in appearance and habit that they are kept separate for business purposes. A great trade is done in varieties of the Japanese C. obtusa, some of the best-known forms being albo-picta, aurea, compacta, filicoides, gracilis aurea, lycopodioides, nana, and plumosa - names which convey an idea as to habit or appearance and colour. There are several forms of the feathery plumosa, such as albo-picta, argentea, aurea, etc. P. pisifera is another elegant variety of obtusa, more graceful and slender in appearance. There are many forms of it, including filifera (fig. 452), f. aurea, and squarrosa. The plant known as leptoclada is probably a form of Cupressus thyoides (P. ericoides), and has a nice pyramidal habit. Amongst other varieties of obtusa are Crippsi, a fine golden one, with dwarf and slender forms.
Fig. 452. - Retinospora filifera.