404 THE NURSERY-MANUAL 



peach, while on the plum they may persist twenty-five years or 

 more. See Almond. 



The ornamental cherries, peaches, and the like, are propagated 

 in essentially the same way as the fruit-bearing varieties. P. Lauro- 

 cerasus and P. lusitanica, the cherry laurel and Portugal laurel, 

 may be propagated by short cuttings of ripened wood, in a cool 

 greenhouse in autumn. P. Pissardii propagates by cuttings of the 

 soft wood and, with more difficulty, from cuttings of dormant wood. 

 Soft cuttings succeed well with many of the double-flowering plums 

 and cherries, if the wood is grown under glass. See Apricot, Cherry, 

 Peach, Plum. 



Pseuderanthemum. Acanthacece. 



Propagated by greenwood cuttings any time from March to 

 June. To this genus are now referred the plants commonly known 

 as Eranthemum. 



Pseudolarix (Golden Larch). Pinacece. 



Should be raised only from seeds ; if grafted on its own roots 

 or on common larch, it rarely grows into a symmetrical tree. 



Pseudotsuga. Pinaceas. 



Propagated by seeds, as for abies and pinus ; varieties may be 

 grafted on the type. 



Psidium : Guam. 



Psoralea. Leguminosce. 



Propagated by seeds, divisions and cuttings of growing shoots 

 under glass. The tuberiferous species, as the " pomme blanche " or 

 Indian potato (P. esculenta), are increased by the tubers or divisions 

 of them. 



Ptelea (Hop Tree). Rutaceae. 



Multiplied by seeds, sown in autumn or stratified, and also by 

 layers. The varieties may be grafted on the common forms in spring 

 under glass or budded in summer on seedlings of the type. 



Pteris (Brake. Bracken). Polypodiacece. 



Easily grown from spores and by division of the rhizomes. See 

 Ferns, page 312. 



Pterocarya. Juglandacece. 



Handled by seeds sown in autumn or stratified, and by suckers 

 and layers. 



