301 
iMr. Dodwoll considers “ the trees liavo been injured by the 
oxtrenie cold and long continuance of frost only.” 
IMr. Ijii.xton attributes the mortality Avhich ho has observed 
among not only Lombardy Poplars, but also among lUrches and 
Alders, to the excessive rainfall. 
^Ir. Amyot “ attributes the mischief rather to the sudden 
changes of temperature, than to tlio extreme severity or long 
continuance of the frost ; for I remember winters as severe and as 
long in which Oaks and other trees have suffered, but I never 
recollect to have seen the Lombardy Poplar seriously injured till 
now. One of the sudden changes to which I allude occurred at 
(diristmas time, Avhon beautiful, milil ainl open weather was 
immediately succeeded by intense and continued frost.” 
]\[r. T. L. Reed says ; “ The long-continued frost, after such a wet 
season, destroyed the trees in a .similar manner to the winter of 
18G0, which was just such a sea.son.” 
Dr. Lowe says: “It appears to mo that it was loth the low 
tempenature and its long continuance to which wo must assign 
the remarkable efiects of last winter. The low temperature alone 
will not yield suflieient cause, for, if I mistake not, in 18G0, with 
a lower temperature, there was no such universal destruction of 
these trees.”. Dr. Lowe’s view, that the root structure of the 
Lomb.ardy Poplar renders it peculiarly liable to injury in long- 
continued ground-frost, has already been quoted under the replies 
to the Third (Question. 
^Ir. I'rcro says: “I am (piite at a loss to give a reason for the 
specially pernicious cflbct of last winter. The seasons in 1 860— 6 1 , 
"0 — 71, and 79 — 80, h.ad a tempor.ature (extreme) about as low, 
but no dam.age was done, .so far as I know.” 
Lord Walsingham s.ays : “ Severe frosts in February, occurring 
when snow hanging on the trees w.as partually melted. This killed 
all young shoots and unripe wood. The snow prob.ably hung and 
dripped more on the north side.” 
Dr. Good.acre “can only suggest, that the sharp cutting wind of 
January 18th m.ay have been the chief cause of the h.avoc among 
Lombardy Poplars ; and perhaps their peculiar manner of gi’owth 
made it tell on them in a way it did not on other forms of Poplar.” 
Mr. (,’andler writes : “ I am afraid I have nothing to s.ay on this 
point. It is curious that last winter should have proved so fatal. 
