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Our older trees must have stood without injury many long severe winters before last (as 1860-61, when so much damage was done in the London Parks). In parts of Northern Italy, too, where this tree is very abundant and, I believe, indigenous, the winters are often severe and protracted."

But the following replies seem to agree in ascribing the effect to a common, and, as I venture to think, the correct cause of the fatality.

Mr. Dowell "attributes the fatality to the severe cold of last winter acting on trees whose constitution had been weakened by a succession of unfavourable seasons. The extreme cold winds of June, 1880, killed or nearly so the young foliage of the Poplar and other trees; and though the trees put forth a second crop of leaves, it was but a sickly one, and the young wood never ripened so as to stand the severe winter."

Mr. Ling "considers the wet and low temperature of the two previous summers (nearly sunless) being a great cause, and the severe frost in the winter following entirely completed the destruction."

Mr. Du Port thinks "that the cause of the damage was the severity of the frost affecting wood that had not been thoroughly ripened, owing to the damp and cold summers of 1879 and 1880. Many trees near Mattishall had but very poor foliage in 1880, and lost it very early."

Sir Willoughby Jones says: "The cause of this mortality is, doubtless, the insufficient ripening of the young wood in the summer of 1880. I think that, apart from the tree being more tender than the other Poplars, its mode of growth, and the close packing of its branches and young shoots may explain the insufficient ripening of its wood."

Mr. F. Norgate "is of opinion that the Lombardy Poplar is less hardy here than the other Poplars, and is unable to stand the last two severe winters."

In fact, we must look back to the year 1879 for the real origin of the mischief which showed itself in 1881. And in proof that this is the correct solution of our problem, I will call but one witness, the Registrar-General. Let us hear what he has to say about the season of 1879-80.

July, 1879,"was dull, very cold, and sunless, with many days of temperature seven to nine degrees below their averages. Rain

fell on every day during the first half of the month, and snow at Bolton on both the 4th and 8th, and at Cockermouth on the 9th." August, 1879, "was a cold and very wet month."

September, 1879, "from the 6th rain fell almost daily."

"The weather during the whole Quarter ending September, 1879, has been cold, wet, and sunless, being a continuation of the bad weather of the eight preceding months."

"The eleven months ending September, 1879, had a mean temperature of 46.14-there are only two such seasons in this century, 1813-14 and 1815-16.”

"The rainfall for the nine months ending September, 1879, was unprecedented, amounting to twenty-nine inches. The year 1828 was the nearest, but that was 2 inches less."

October, 1879, "was dull and sunless."

November, 1879, "exceedingly cold."

December, 1879, "remarkably cold, and was the fourteenth month in succession of low temperature. On the 7th there was a minimum temperature of 1 degree at Cambridge, Nottingham, and Stockton."

January, 1880, "was exceedingly cold, and was the fifteenth month in succession whose mean temperature was below the average. The mean temperature of this month was 5 degrees below the average for 39 years."

Let us hear the same witness as to the season 1880-81.

October, 1880. "The mean temperature of the air was 3 degrees below the average of 149 years. Going back to 1771, there are but seven years in which this month had so low a mean; and but three years in this century, 1808, 1817, 1842. The rainfall was exceptionally large; it was the coldest October since 1842, and the wettest on record."

November and December had about the usual average of both temperature and rainfall.

January, 1881. "The weather from the 12th to the 27th remarkable for its severity; there was snow every day from the 9th to the 27th, excepting the 25th," and we all remember what the 18th was.

Now, the Lombardy Poplar is a native of Persia, and the date of its introduction into Lombardy is unknown; but though it was carried to England by Lord Rochford, ambassador at Turin, in 1758, it did not reach Tuscany till 1805, thus showing that it did not

spread very fast even in Italy: It is a tree of very rapid growth, often attaining the height of 60 or 80 feet in less than thirty years (one case of 125 feet in fifty years is recorded), and consequently its wood is of very soft and spongy texture. But one sex, the male, was brought to England, though both sexes are extant in Lombardy; and it has ever since been propagated here by sucker, and not from seed; and we know that this method of propagation produces debility of constitution, and inability to withstand the attacks of any enemy, disease, or hardship. What wonder then, that a halfhardy tree of weakened constitution, when exposed to the hardship of eleven months continued low temperature, such a season as had not been experienced in this country for sixty-five years, and to a rainfall during nine out of those eleven months "unprecedented," amounting to 2 inches more than had ever before been registered in this country in the same space of time, should sicken, and being exposed during the winter which followed (1879-80) to a December "remarkably cold," with a minimum temperature of -1 degree in the Eastern Counties, and then to a January with a mean temperature 5 degrees below the average of thirty-nine years, making a total period of fifteen months successively, of unusually low temperature, should fail to recover itself in the summer of 1880; and being again subjected to the coldest October for thirty-nine years, and the wettest on record, followed by the furious snowstorms and severe frosts of last January (1881), should succumb to so long a period of abnormally unfavourable conditions; and even should the fungoid disease theory of Mr. Purdy, or the peculiar root structure of Dr. Lowe, be confirmed by future observations, I think we shall still be justified in considering the fifteen months' low temperature which continued to January, 1880, and the unprecedented wetness of nine of those months, as the predisposing causes which weakened the tree and deprived it of its power of resistance, either to the attacks of disease, or to the winter of 1880-81. And thus is explained the riddle, that trees which survived 1860-61 died from the effects of the less severe winter of 1880-81, for they had not in the former of these two seasons suffered fom the same special weakening circumstances.

Mr. Purdy of Aylsham, has made a most excellent suggestion, that those who possess dead or dying Lombardy Poplars, should convert them from unsightly into beautiful objects by planting at

their feet Ampelopsis tricuspidata, the smaller Virginian Creeper. He says: "I have several plants in my own ground, draping the boles of living trees, which at the present moment are extremely beautiful in their livery of deep carmine."

At about the same time as our Secretary issued his circular, Mr. Southwell wrote to both the 'Field' and 'Land and Water,' asking for information as to the extent of injury beyond the limits of the county. These letters produced many replies, some published in the same newspapers, and others addressed privately to Mr. Southwell, who has kindly allowed me the use of them.

In 'Land and Water,' Oct. 15th, 1881, Mr. H. P. Malet, writing from Florence, says: "Much damage was done to many kinds of trees in France, Switzerland, and Germany, in the spring of 1880." The main destruction over many hundreds of square miles was done in the spring of 1880.

In the 'Field' of the same date: "Twenty miles round York, the death or severe injury of Lombardy Poplars is almost universal. I have been unable to learn any satisfactory explanation of this result, except that the three past winters and sunless summers have been quite exceptional. (G. O.)" "The area of destruction seems to extend over the whole of the eastern and east midland counties of England. (P.P.W.)" And the editor sums up by saying that "the extensive destruction of the Lombardy Poplar is corroborated in letters from many correspondents."

In replies privately sent, Mr. W. Brown writes: "The Poplars throughout the county of Wilts have suffered very much."

Mr. J. M. C. Montagu: "Most of the Lombardy Poplars in West Dorset were killed or seriously injured last winter."

Mr. Ross Mahon writes from Monkstown near Dublin: "All such trees in this neighbourhood have been injured by frost, most of them killed outright. I noticed this early in 1880 when they should have come into leaf, so the frosts of 1879 were severe enough to affect them."

Mr. G. J. Mather finds "near Doncaster all are more or less killed."

And in replies to our Secretary's circular, we find from Mr. Frere: "I should say the Poplars in Leicestershire are injured in about the same degree as those in our own county."

VOL III.

BB

Lord Walsingham "hears of similar injury and extensive destruction of Lombardy Poplars on his property in Yorkshire and in Cambridgeshire."

But Mr. Du Port says: "At Oxford, among the college gardens, it is the exception to find a damaged tree."

Mr. C. B. Plowright: "The Lombardy Poplars in the West of England do not seem to be injured at all."

And Mr. Dowell writes: "Travelling from Norfolk to North Wales in the end of June, through the midland counties, I noticed that the Lombardy Poplars were less and less injured the further I went west. In Wales they were not hurt."

From these answers it appears that the injury is greatest in Eastern and East Midland England, extending as far north as Yorkshire, but that it grows less (so far as England is concerned) in proportion as we travel westward, until in Wales the trees "were not hurt" (Mr. Dowell), and in the West of England they "do not seem to be injured at all" (Mr. Plowright); and it is curious how this gradation of injury seems to coincide (possibly fortuitously) to a certain extent with the frost of the 7th December, 1879, when there was at Cambridge, Nottingham, and Stockton a minimum temperature of -1 (one degree below zero); at Cardington in Bedfordshire, +2; Leicester, +4; Hull, +7; Oxford, 11; Greenwich, Marlborough, and Wolverhampton, 13; Bournemouth, 16; Bath, 18; Stonyhurst, 20; Plymouth, 21; Liverpool, 22; Barnstaple and Torquay, 27; and Llandudno, 28. Of course, I am far from asserting that it was this frost alone which did all the mischief; but it is a strange coincidence, that the injury should, to so great an extent, coincide with the intensity of the cold of that the coldest day of the first of the two winters we have been considering, when the seed of the mortality of the seasons following seems to have been sown.

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