SALICINEiE 



Leaves attached by Black Poplar Rust {3Ielampsora populina) and Poplar- 

 leaf Blister {2\iphrina aurea). Large green and pinkish galls on petioles 

 produced by an Aphis {Pemphigus bursa7-ius). 



LOMBARDY POPLAR, Populus nigra, V. pijramidalis. 



Parks, gardens, hedges. March, April. It is characterised by rapid growth 

 and early decay. 



Trees in England almost invariably bear male catkins only ; Stamens 12-20. 



Leaves resembling P. nigra ; young leaves glabrous. 



A deciduous tree, 100-150 ft. ; Branches growing straight upwards, giving a 

 spire-like shape, young shoots smooth ; growth very rapid ; Barh rough, deeply 

 furrowed ; Buds viscid ; Wood tough and light, of little value ; trees often 

 unsound, though apparently healthy, and liable to fall without warning. 



Native of Asia ; thought to be a variety of P. nigra ; introduced to England 

 from Italy by Lord Rochford in 1758, and planted near the priory of St. Osytli, 

 not far from Clacton-on-Sea. Syn. P. fastigiata, from \j. fastigiatus, sloping 

 up to a point, — -fastigo, to make pointed. 



ASPEN, Populus tremula. 



Moist woods, gardens. March, April. 



Flowers dioecious ; Catkins sub-sessile, curved, dense, cylindrical, 2-3 ins. 

 long, scales ciliate, with jagged edges ; Stamens 6-12, anthers purple-red ; 

 Stigmas 2, deeply bifid, purple-red, arms radiating crosswise ; Fruit a capsule, 

 stalked, greenish-brown, valves recurved, catkin 5 ins. long. 



Leaves scarcely cordate, nearly orbicular or rhomboidal, small, often not 



1 in. broad, 1— t ins. long, irregularly and rather coarsely sinuate, with 



incurved teeth, acute, thin in texture, underside glabrous and sometimes 



pale, but not cottony ; petiole slender, causing constant trembling ; leaves 



on suckers cordate, entire, acute. 



A deciduous tree, 40-80 ft. ; Branvhes slender, spreading, compressed ; shoots 



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