1 8 14 The Trees of Great Britain and Ireland 



branches, and quickly produces clean stems with useful timber. Prof. Voglino,^ who 

 has made a careful study of the poplars in cultivation in the park of Santena, near 

 Turin, states that this species grows more slowly, but attains a greater height than 

 P. serotina. The wood, though slightly darker in colour, is much stronger, and is 

 always very free from knots. Young trees, however, have brittle branches, which 

 suffer severely even from slight falls of snow. (A. H.) 



History of the American Black Poplars and their Hybrids in Europe 



P. angulata was early introduced into France, as it is mentioned as a well-known 

 tree by Duhamel du Monceau,^ who described it in 1755 as the "peuplier noir de 

 Virginie a tres grandes feuilles, et dont les jeunes pousses sont relevees d'aretes qui 

 les font paraitre quarrdes." This species was in cultivation' in England in 1738. 



The second American species of black poplar, P. monilifera, Alton, appears 

 also to have been early introduced into France, where, according to Michaux, it was 

 probably imported from Canada. He accurately describes it under the name P. 

 canadensis, and states that in cultivation it did not succeed in compact and clay soil 

 and frequently branched into two near the base of the trunk. It was mentioned* by 

 Fougeroux de Bondaroy in 1 786 as the Peuplier de Canada, though he also called it 

 P. virginiana, and states that he had only seen the pistillate tree. It is said^ to have 

 been introduced into England in 1769. 



Poplars hybridise very freely, especially in France, where seedlings are much more 

 frequently found ^ than in England ; and probably the first hybrid to be selected was 

 the tree now known as P. serotina, which, according to tradition, has been known in 

 France as th&peuplier Suisse since the middle of the eighteenth century.'^ Its botanical 

 characters show that it is a cross between one of the two American black poplars, 

 presumably P. monilifera, and the glabrous form of the European P. nigra. It is 

 quite unknown in America.* Michaux, who erroneously named it P. monilifera in 1 8 1 3, 

 is clear on the subject, as he states that " neither my father, myself, nor any of the 

 educated English who traversed the Atlantic states, and a great part of the states of 

 the West, ever found this species of poplar." He adds that it was commonly called 

 peuplier suisse because it was more cultivated in Switzerland than elsewhere ; and 

 that only the male tree existed in France, which was always propagated by cuttings. 



1 I Nemici del Piofpo Canadense di Santena, 8 (1910). This valuable work, pp. 130, figs. 1-16, appeared in Ann. R. 

 Acad. Agric. Torino, liii. (1910), and gives an account of the fungoid and insect enemies of the cultivated black poplars. 



'■^ Traiti des Arbres, ii. 178, pi. 38, fig. 8 (1755). The figure represents exactly P. angulata. 



^ A branch, gathered by Miller in the Chelsea garden in 1738, is preserved in the British Museum. 



* In M4m. d' Agric. Paris, 1786, p. 87. 



^ Loudon, Trees and Shrubs, 825 (1842), under P. canadensis. 



6 Loudon, Trees and Shrubs, 827 (1842), stated that many thousands of seedlings came up annually in the walks of 

 Fontainebleau, most of which were destroyed, but some varieties had been selected from them. 



' It seems to have been the poplar described and figured by Duhamel, Traiti des Arbres, ii. 178, pi. 39, fig. S ('7SS), 

 as "P. nigra, foliis acuminatis, dentatis, ad marginem undulatis, ou mal 4 propos osier blanc." It was supposed by Duhamel 

 to be a variety of P. nigra, and was planted in vineyards, instead of willow, where it was treated as coppice, the shoots being 

 cut annually. Fougeroux, in Mini, d' Agric. Paris, 1786, i. 80, states that it grew with great vigour even in dry soils, and 

 was called osier blanc in the districts south of Paris, and alain in other places. 



5 Prof. Sargent assured us that he had seen no tree in America which resembled P. serotina. 



