THE NURSERY-LIST 393 



P. nivosus grows readily from root-cuttings, P. acidus and P. Em- 

 blica may be grown from seeds ; the latter also by layers. 



Phymatodes. Polypodiacece. 



Spores and division. See Ferns, page 312. 



Phy sails (Ground or Winter Cherry. Strawberry Tomato. Husk 



Tomato). Solanacece. 



Propagated by seeds, sown outdoors or under cover ; perennials 

 by division of the rhizomes and soft cuttings. 



Physocarpus (Ninebark). Rosacece. 



Propagated by hardwood or greenwood cuttings and by seeds, as 

 for spiraea. 



Physostegia. Labiates. 



Division of strong clumps may be made readily ; also grown from 

 seeds, as are other herbaceous perennials. 



Phyteuma. Campanulacece. 



Propagated freely by seeds, and division in spring. 



Phytolacca (Scoke. Poke). Phytolaccaceoe. 



Propagated by means of seeds, or by division of the thick roots, 

 usually the former. 



Picea (Spruce). Pinacece. 



Propagated by seeds, sometimes by layers, sometimes by grafts ; 

 also by cuttings of recent wood. Seedlings must be shaded the first 

 year. The spruces are easily grafted. P. excelsa (Norway spruce) 

 or P. canadensis (alba) makes a good stock; the veneer-graft, 

 under glass, in winter, succeeds better than any method of outdoor 

 work practicable in our climate ; if the graft is inserted near the 

 base in young plants, it is quite possible to obtain them on their 

 own roots after a few transplantings. Side shoots can be used as 

 cions, and if started in time will furnish good leaders ; sometimes a 

 leader is developed more rapidly by bending the plant over at 

 nearly a right angle, when a stout bud may start from the stem. 

 The balsam fir is also a good stock for flat-leaved species. See 

 Abies. 



Pieris. Ericaceae. 



Propagation by seeds and layers and the evergreen kinds by 

 cuttings of almost ripened wood in August under glass, kept 



