This poplar has the general character of P. balsamifera, the same sucker-producing habit, balsamic resin-covered buds, and odoriferous young foliage; also the whitish undersurface of the leaf conspicuously netted over with veins. But it differs in the following respects: its branches are more spreading than in P. balsamifera, and it thus forms a broader, more open crown; its leaves are broader and more generally heart-shaped, more downy beneath, and ciliate; and its leaf-stalks and young shoots are downy. It is a female clone the history of which is unknown, but most probably it arose in north-eastern N. America, where it has been cultivated since early colonial times as a shade tree, and was introduced from there to Europe in the 18th century. In Britain it has been known since 1773. Some authorities hold it to be no more than a clone of the north-eastern variety of P. balsamifera known as var. michauxii or var. subcordata, but according to another view it is a hybrid between P. balsamifera and P. deltoides.
At one time P. candicans was the commonest balsam poplar in Britain. In previous editions of this work it was said that it ‘may often be seen in out of the way places in London suburbs, producing a swarm of suckers, and scenting the air around on moist spring days’. Unfortunately that is no longer true, for this poplar is very susceptible to bacterial canker and has become rare.
cv. ‘Aurora’. – Leaves variously patterned with white flushed pink; some are marbled, other broadly margined with it, a few more white than green. But many leaves are wholly green, especially on the spurs, the variegation being best developed in summer on the long shoots. Hard pruning encourages the production of long shoots but perhaps also makes the tree more vulnerable to attacks of canker unless the cuts are sealed with a proprietary dressing. ‘Aurora’ was put into commerce in the 1920s by Messrs Treseder of Truro, who obtained their stock from a garden in north Devon. It was originally distributed as P. candicans variegata and received its present name in 1954; the Award of Merit was given to it in the same year.
There is also a yellow-variegated form of P. candicans in cultivation, which received an Award of Merit in 1898, as “P. ontariensis variegata”. There are plants in the Forestry Commission collection at Alice Holt, heavily infected with canker.