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THE FLOWER GARDEN. 
Populus (Poplar). — The Poplars belong to the Willow 
order (Salicaceae), and are hardy deciduous trees of free and 
lofty growth. Their chief value in the garden is their adapta- 
bility for rapid growth, and thus making good boundary 
screens. In small suburban gardens they are quite out of 
place, their branches shading the garden far too much and their 
roots robbing the soil of moisture and nourishment. It is far 
better to plant trees of more moderate growth that flower freely 
in spring or summer. In larger gardens the Black Poplar 
(P. nigra) and its variety, the Lombardy Poplar (P. nigra 
pyramidalis) may be planted ioft. apart to serve as a boundary 
screen till other trees grow large enough, then they should 
be removed. Where the gardens are still more extensive 
Poplars may be planted singly or in groups to make a bold 
effect in years to come. They may also be planted in damp, 
low-lying places, such as the fringe of a watercourse. Here 
they will display their natural beauty to advantage. The 
Balsam Poplar (P. balsamifera) and the Lombardy Poplar make 
good, quick-growing and lofty hedges if planted thickly and 
their sides are kept well trimmed. The best of the Poplars 
are the Aspen (P. tremula), a species growing 50ft. high, with 
grey bark and heart-shaped leaves, which continually exhibit 
a tremulous motion. P. alba (Abele or White Poplar) grows 
upwards of 60 to 80ft. high, has also grey bark and ovate 
leaves. It is a handsome tree when fully grown. P. nigra 
(Black Poplar) grows 60ft. high, has roundish leaves and 
whitish, downy, resinous young shoots. The Lombardy Poplar 
(P. nigra pyramidalis) is the well-known tall and slender- 
growing pyramidal kind. P. balsamifera (Balsam Poplar) has 
ovate leaves, and its buds are coated with a resinous substance 
of a balsam-like odour. The Necklace or Canadian Poplar 
(P. deltoidea), known also as P. canadensis and P. monolifera, 
has heart-shaped leaves, and is a tree of handsome growth. 
Its variety aurea has golden foliage. There is also a Weeping 
Poplar, a variety of P. grandidentata. All the Poplars prefer 
a moist soil, and should be planted in autumn. Increased by 
seeds sown outdoors in spring or autumn ; by cuttings inserted 
outdoors in October ; and by suckers. 
Ptelea. (Hop Tree). — A genus of hardy deciduous shrubs 
with foliage possessing a hop-like odour. P. trifoliata is a 
native of N. America, grows 6 to 8ft. high, has trifoliate leaves, 
and bears greenish flowers in summer, succeeded by hop-like 
seed vessels. It belongs to the Rue family (Rutaceae). The 
golden-leaved variety, aurea, is the only one we can recommend 
for general culture. It succeeds in ordinary garden soil, and 
should be planted in autumn. Increased by cuttings of 
ripened shoots in a cold frame in autumn. 
