Читать книгу Trees and Shrubs for English Gardens - E. T. Cook - Страница 23

Table of Contents

First among Poplars to bear its flowers, and almost before winter is past, is the Aspen (Populus tremula). This and its weeping variety bear their catkins in February, but closely following it, and perhaps more ornamental, is the American Aspen (P. tremuloides). This species flowers early in March near London in mild seasons, but later further north, and when kept back by severe weather. The pendulous variety of P. tremuloides—known commonly as Parasol de St. Julien—is, at the flowering time, probably the most beautiful and striking of all catkin-bearing trees. This and also the type produce long, slender catkins that sway gently in the softest winds. The weeping variety, which has branches that weep naturally low, looks well by itself on a lawn. In all these Poplars the male catkins are three inches to four inches long, chiefly grey-brown in colour; the scale-like bracts, however, are suffused with a reddish shade. The weeping varieties of these two Aspens are frequently grafted on the White Poplar, which is not a suitable stock. The species to which the varieties severally belong should be used for the purpose. It would be even better if they could be got on their own roots by means of layers or cuttings, and trained up to the required height before allowing the weeping habit to develop.

There are other Poplars that bear their catkins freely, such as P. alba, nigra, and balsamifera, but being of loftier habit they do not show to the same advantage as those of the Aspen group.