Article (magazine)  (Jan 1955)  Page(s) 12.  
 
Robert Fortune, the great explorer of the Royal Horticultural Society, made four trips to China and introduced many fine plants to England. In 1846, he brought twenty-five of the finest tree peonies ever to come out of China. Among these were 'Atrosanguinea,' 'Berenice,' 'Bijou de Chusan,' 'Dr. Bowring,' 'Globosa,' 'Glory of Shanghai,' 'Lord Macartney,' 'Pride of Hongkong,' 'Robert Fortune,' 'Samarang,' and 'Zenobia.' These were enthusiastically received and quickly propagated, so that both British and continental nurseries cataloged them in some quantity in the 1860's.

Website/Catalog  (1924)  Page(s) 152.  
 
Pivoines en arbre...Zenobia.- Gr. fl. violet pourpre bleuâtre.

Book  (1907)  Page(s) 231.  
 
2701. ZENOBIA; P. moutan.
(1) 1863, Revue Horticole, p. 292.
(2) 1885, The Garden. Vol. 27, p. 33.
(3) 1899, L. Paillet's Cat.
(4) 1906, Dessert's Cat., p. 44.
(5) Cornell Plot No. 1600.

Book  (1898)  Page(s) 108.  
 
La Pivoine en arbre a fourni à la culture un grand nombre de variétés horticoles, les unes obtenues en Chine, et d'autres en Europe...Quant aux variétés horticoles, elles sont si nombreuses que nous ne pouvons citer que les plus remarquables.
Principales Variétés Horticoles
Zénobia Fortune (Chine).—Grande, double, rouge pourpre.

Website/Catalog  (1893)  Page(s) 42.  
 
Tree Pæonies.  Pæonia Arborea.
This beautiful group of shrubs is among the oldest of introductions from Japan, but magnificent new varieties have been added from year to year until we have a long list of wonderful forms.  They are quite distinct from the herbaceous section, and have shades of color not found in the latter; and when once established form compact bushes, which in spring are covered with the gigantic blooms.  These pæonies are a little tender in exposed situations north of Boston; but if planted in a sheltered, warm location, and protected during the first two winters by a covering of pine boughs, or other loose material, will eventually establish themselves, and form one of the most decorative features of the garden.  Like the herbaceous kinds, they enjoy rich soil, and the blooms last longer and come finer when partially sheltered from the hot sun.  They are well worth the little trouble entailed in their cultivation.  We can offer strong plants of the leading and most hardy kinds; but as they are slow and difficult of propagation, this fact will account for their relatively higher cost over the herbaceous kinds.  Having secured a large stock of these beautiful plants, we are enabled to offer them at lower prices than ever before.  2 year plants, 75 cents each; 3 year plants, $1.00 each.
Zenobia.  Large blossom, violet purple, shaded bluish; a full centre of golden-yellow stamens.

Website/Catalog  (1890)  Page(s) 33.  
 
Pæonia Arborea (Tree or Moutan Pæonies).
General Collection. 
Zenobia, double, dark maroon.

Magazine  (22 Jan 1887)  Page(s) 77.  
 
The Tree Pæony. 
...For the last twenty years or longer we have had to look to our French neighbours for new sorts of Tree Pæony, for since they have taken the work of hybridising and raising seedlings in hand they have supplied us with all the finest sorts.  Until now the list is long- too long, in fact, for names are given where very shadowy differences exist.
List of select Varieties.
Zenobia, purple-crimson

Magazine  (10 Jan 1885)  Page(s) 33.  
 
Tree Pæonies.
By way of reply to Mr. Frank Miles, who seeks information respecting Tree Pæonies, I send you herewith the names of the original Chinese varieties, all or most of which were introduced by Fortune:
Zenobia... 

Website/Catalog  (1876)  Page(s) 26.  
 
Pivoines en Arbres.
9 Zenobia (Fortune)...3 fr.
Grandes fleurs rouge pourpre foncé.

Magazine  (1874)  Page(s) 25.  
 
Mr. W. C. Barry... presented the following report:
On Tree and Herbaceous Pæonies.
Tree Pæonies fill up a blank between deciduous flowering-trees and flowering shrubs.  In mixed borders they are invaluable, as well when grown as single specimens on the lawn.  They are quite hardy, but slight protection greatly improves them. [...]
To assist those who desire to form a collection we name the following choice sorts.  Any description, however complete, would fail to do them justice, so we give only the distinguishing colors. 
Zenobia. — A large fine white variety.