Poplar, Populus. A large tree which is native to the temperate climates of Europe and North America. It forms a straight stem which does not merge with the branches but remains continuous up to the peak. The crown is furnished with a large number of twigs which are spindly and somewhat curved because they are naturally ascending. The yellowish bark is smooth and even for a long period, becoming fissured only when the tree has aged. The strong roots anchor themselves quite deeply in the ground. The leaves are smooth, crentate, green-brown, and somewhat rounded at the base; they terminate rapidly in a point. Not all of the trees are seed bearing: the male and female flowers spring up on separate trees. The male flowers are catkins of a fine russet: they appear at the beginning of April and fall after two or three weeks. The female flowers which contain the ovules are grouped on filamentous peduncles. [1] They are shaped like the male catkins but are grass coloured and fall much later, when the seeds, which are small with an apical tuft, ripen towards the end of May or the beginning of June and are dispersed by the wind.

The poplar is among the finest trees and one of the foremost to thrive in wet sites. It grows promptly, propagates readily, and withstands all inclement weather. It has a number of uses which are of great benefit to society.

While the poplar can grow in different soils, it thrives best in wet sites, on the edges of ponds, alongside rivers and streams, and especially on the banks of water-filled ditches. It springs up more readily in valleys than plains, which it none the less prefers to hillsides: it languishes on high ground, decays in dry, sandy soils, and is not long- lived in soils which are clayey or too heavy or hard.

This tree may be propagated from suckers, layers, or cuttings, but the last method is the simplest, quickest, and most reliable. The cuttings are taken at the end of winter as soon as the ground is workable. It is absolutely necessary to select the strongest, most vigorous, and smoothest shoots of the current season’s growth, since wood which is two or three years of age is unsuitable. The shoots are cut to a length of twelve or fifteen inches and are driven into the ground by being buried and turned until there is a single bud at the top which can shoot upright. These cuttings should be no more than two or three buds above the ground, and may be planted in the site in which they are to be cultivated at intervals of twelve or fifteen inches and in rows 2 or 2½ feet apart. They may be left to grow freely in their first year, but the following spring all of the shoots should be removed except for the one which seems most disposed to grow upright. In subsequent years, the young trees should be pruned as they gain in strength, but each year those saplings which have sprung up badly should be cut back to their bases to enable their stems to regrow. After four or five years, these trees are generally ten or twelve feet tall and may be permanently transplanted. They are full grown after twenty-five or thirty years.

The poplar takes again readily following transplantation and one may prune it at any time without detriment, not in the manner of willows which are entirely pollarded, but by cutting back all of the branches close to the main stem, leaving a cluster of branches at the top. This method of training the poplar, which is repeated every four or five years, is the most suitable when one wishes to make use of the wood. One may even cut it more frequently into lops in October: these twigs are dried with their leaves and make excellent winter fodder.

Poplar wood is yellowish, supple, quite hard, and reasonably solid, but somewhat difficult to split. One can make pieces of carpentry wood from it for modest buildings, and even hardwood planks as long as they are protected from damp. Sculptors use it in place of lime wood and it has some uses in joinery, turnery, clog making, etc.

This tree has some medicinal properties: when the sap begins to rise in spring, the eyes or buds become filled with a sort of fragrant, viscid resin, of which the natural virtues cause it to be used in the composition of a balm known as populeon, which is recommended on several counts. [2]

Here are the different species or varieties of poplar.

1. Black poplar: it is to this species that the above description particularly applies. [3]

2. Black poplar which is commonly known as ‘white willow’ because country dwellers use it as an alternative to osier rope in viticulture, clipping it in the same manner, though it is less suitable than osiers for tying vines. [4] The leaf margins are more deeply crenate and sinuate, which is what principally distinguishes it from the common black poplar. [5]

3. Black poplar from Lombardy: an attractive cultivar which has been newly acquired from Italy, where it is highly regarded. [6] Its beauty lies in the dark, yet vivid, glossy green of the leaves which resemble those of the white willow. Moreover, this green colour remains consistent and does not darken in late autumn like that of common black poplar leaves. An even more pleasing feature of this tree is its crown, which is more pyramidal than that of other poplars because the branches are more sharply ascending, making this tree suitable for forming grand, conspicuous avenues.

4. Canadian poplar: another variety of black poplar which is not without merit. [7] It has more body than the black poplar and its crown is more densely furnished with strong, stout, more broadly spreading twigs. However, the main stem does not peak and the tree is smaller. The young twigs are ribbed, but the ridges are far less pronounced than those of the Carolina black poplar which is described below. The yellowish bark soon becomes deeply fissured. The leaves are larger, thicker, more obtuse, and paler than those of the black poplar. The Canadian poplar is still rare in France. I do not know the male tree: all of my young trees are female; the broadest, which is twelve years of age, is thirty-five feet tall, with a girth of three feet and a crown as round as that of a lime tree. The stem grows to eighteen feet and the bark is deeply furrowed, though this is not unattractive because the fissures run into one another as they soften: they form varied sections of a uniform yellow. When the sap begins to rise in spring, the buds swell and spread an extremely pleasant, balsamic fragrance. The following June, filamentous capsules fall which are three, four, or five inches long. Remarkably, however, each valve, which contains or should contain seeds, is filled with down, which is more silklike than cotton and just as white, and collects around the capsules. The tree produces it in such abundance that the ground near the tree base is carpeted with it when the capsules have fallen. One may find a means of employing this substance in the arts. By comparing branches nine inches round lopped from the Canadian poplar, black poplar, and quaking aspen, it was found that the wood of the Canadian poplar appears to be between the black poplar and the quaking aspen for colour and consistency. This tree would be most suitable for forming avenues: it has a better bearing than the black poplar and is more attractive and just as hardy. It thrives in cool, damp soil, but those which we planted in dry, elevated ground soon decayed and finally perished.

5. ‘Fragrant black poplar’, tacamahac, balsam poplar. [8] This tree is native to Carolina, where it is found only on riversides and is tall and spreading. However, it is far from making the same progress in Europe: Mr Miller, the English author, affirms that the tallest English specimens are only fifteen or sixteen feet, and French specimens are even smaller. The balsam poplar grows a fairly straight stem with spreading branches. The bark on the young twigs is dark russet. The large buds are always filled with a yellow, viscid, balsamic resin, which is strongly but not unpleasantly fragrant. When the sap begins to rise, this resin flows more abundantly and overflows at the leaf insertions on the young shoots. It is then more fluid and strongly fragrant. The leaves appear early in spring, from the end of February: they are bright yellow, becoming pale green before turning a dull, green-brown above and a dull, yellow-white beneath. The leaves are large, heart-shaped, faintly dentate, and acute. I have as yet seen only male catkins of this species: they appear with the leaves and are broader, longer, and of a more striking red than those of the black poplar. This tree languishes if it is not planted in damp soil. It can propagate from the suckers which grow from its base, but it multiplies more rapidly from cuttings, which thrive when they are prepared early, from November, and planted in a sheltered site. If they are prepared at the end of winter they are far less certain to prosper. The balsam poplar can also be propagated by layering, but it cannot be grafted on to the black poplar: I shield budded several shot buds on to black poplar rootstocks which took again and grew well during the year, but by the following spring all of the rootstocks were dead and dried up. This serves to demonstrate that it is not sufficient for the solid and constitutive parts of the graft and rootstock to correspond in order to ensure the success of the operation, but that the two saps must also be compatible. I consider this tree to be sufficiently sturdy to survive in the open ground in our climate. The leaves wither and fall early in autumn, even from the end of September, and are quite beautiful in spring and summer. However, the chief merit of this tree lies in its balsamic resin, which could be used in medicine: there is no better cure for cuts.

6. Carolina black poplar. [9] This is undeniably the most beautiful poplar, but it has not long been known in France and England. It has remarkably long leaves, which are often 10 inches long by 8-9 inches wide. The leaf margins are faintly and pleasantly crenate, and are of a vivid, glossy, consistent green. They are attached to the tree by long petioles, which incline in the opposite direction to ordinary petioles because they are flattened, with the result that the leaves of the Carolina black poplar are suspended sideways. [10] Towards the end of summer, the flattened surfaces become tinted with a reddish colour which contrasts markedly with the greenness of the foliage. The growth of this poplar is a phenomenon worthy of admiration: it is the fastest growing tree to thrive in the temperate climates of Europe. It grows and broadens with astonishing speed: saplings of six inches planted in loose, cool soil have in two years been known to grow to fifteen feet, each specimen boasting a girth of 8-9 inches and a crown 8-10 feet broad, formed of 6-8 branches from 5-7 feet long. This tree may be regarded as a plant prodigy. It is also conspicuously ribbed: there are four or five striations on the current season’s growth, and the ridges are prominent and shiny; they soften over time, leaving traces even on the wood of two or three years. I as yet know little of the male flowers, seeds, or wood of this tree: although it is native to the southern regions of California and Virginia, it is nonetheless hardy. It springs up in low- lying sites of any exposure and thrives quite well in rich, loose loam, and above all in damp soil conditions, provided that they are not permanent: it is then that the tree prospers and comes on well. It is propagated from layers which put out few roots in their first year but eventually take root again, from cuttings which succeed reasonably well when they are prepared at the beginning of November, and by grafting on to the black poplar which is quite successful. The Lombardy poplar appeared to me to be a less suitable rootstock. This tree is suitable for forming avenues, allées, and especially salles de verdure and quincunxes, where this tree is more sheltered from strong wind, which can break its branches.

7. White, broad-leaved poplar, which is also called Dutch grey, white poplar, or Picardy cultivar, and, in England, abele. [11] A large tree which does not peak as much as the ordinary black poplar but is broader and more spreading. It grows more promptly than the black poplar, but more slowly than the Carolina black poplar. The smooth, white bark becomes furrowed only when the tree has aged considerably. The leaves are generally heart-shaped and the margins are diversely toothed. The leaves are of a very brown green above and a downy white beneath. The male flowers and seed-bearing capsules appear and fall at the same time as those of the black poplar. The roots are spreading, with the result that the tree is sometimes blown over by the wind. It has the particular merit of growing in any soil, even in relatively dry, elevated ground, though it cannot tolerate chalk, fine gravel, and pure sand. It thrives in soils which are black, rich, and clayey, and makes even more progress in wet, low-lying sites, where it grows extremely vigorously. This tree can withstand all inclement weather. It can be propagated from cuttings or from its suckering roots, which is quicker. It may be permanently transplanted after only three years in the tree nursery. It is naturally protected from cattle, which according to the English author Ellis do not like its leaves. [12] The wood of this poplar is white, soft, light, and easy to split, and is less prone to fissure than many other white woods, which causes it to be used by turners, violin makers, and packing-case makers. Joiners also use this wood, which is excellent for panelling, and above all for parquetry. It is also used by cartwrights for making the wheels of light carriages. Lastly, the white poplar is most suitable for forming large avenues along canals and in marshy terrain, which a great many trees cannot tolerate.

8. White, small-leaved poplar. [13] This tree differs from the white poplar only in the shape of its leaves, which are smaller and less toothed, rendering the tree far less ornamental.

9. White poplar with small, variegated leaves: this tree must be of little ornamental interest, because our English authors do not supply us with any details of it, even though the English are avid collectors of variegated trees.

10. Quaking aspen. [14] This large tree is the basest species of poplar. It nearly always has a leafless and decaying air which degrades it. It is commonly found in woodlands of which the ground is cold, damp, and clayey. It grows a fairly straight stem which does not broaden in proportion to its height. The crown is quite round and the spreading roots throw out a large number of suckers. The ashen bark appears dull, leaden, and dry, as though it were dead. The leaves are almost round and very smooth: their margins are faintly crenate; they are of a striking, pale, grey-green, and are supported by long petioles which are so fine that the leaves tremble at the slightest motion of the air. [15] The male flowers or catkins are among the first to appear: they flower over one month earlier than those of other species and are of a dark, reddish colour. The seed-bearing capsules fall at the end of May. This tree is of no ornamental interest, and has no use apart from that which may be drawn from its wood, which is scarcely suitable for burning and is the most unsuitable poplar wood for crafts. However, joiners, turners, and clog makers use it, and cabinetmakers make veneer frames from it.

11. Small-leaved aspen. A variety of the preceding species, from which it differs in its leaves and especially its volume: the small-leaved aspen does not grow as tall or broad as the broad-leaved species but compensates by its ability to spring up quite successfully in dry, elevated, poorly-conditioned ground.

Notes

1. The author uses the words ‘sur un filet commun’ (on a common filament). On the peduncle, see article Stalk.

2. This calming ointment was used from the fourteenth century and was also composed of narcotic plants.

3. Populus nigra.

4. See article Osier.

5. Populus nigra variety betulifolia, which is now known as the downy black or Manchester poplar (Huxley et al., 1992, iii.689).

6. Populus nigra ‘Italica’, the Lombardy, Italian, or pyramidal poplar. It was introduced to Britain in 1758, shortly before this article was composed (article ‘Platane’, by the same author, was composed in 1761). See D. J. Mabberley, The Plant-book: a Portable Dictionary of the Vascular Plants (Cambridge, 1997), 579.

7. Populus deltoides. The Canadian poplar is the name now given to a hybrid formed from a cross between Populus nigra and Populus deltoides, which is said to have sprung up in the early 1700s in France (Harris, pers. comm.; Mabey, 1996, p. 138).

8. Populus balsamifera variety balsamifera.

9. Populus balsamifera variety subcordata.

10. The author uses the word ‘pédicule’ rather than ‘pétiole’: see article Stalk.

11. Populus alba, also known as silver-leaved poplar (Huxley et al., 1992, iii.688).

12. Ellis actually uses the word ‘shoots’, not leaves (Ellis, 1738, p. 99).

13. This description and the following refer to cultivars of the preceding species.

14. Populus tremula.

15. The author uses the word ‘pédicule’ rather than ‘pétiole’: see article Stalk.