1390 ARBORETUM AND FRUTICETUM. PART Il. 
Brussels (where, in consequence of his suggestions to the local authorities, it 
was found necessary to cut down from 20 to 30 large trees attacked by 
Scélytus destractor in the Park, and from 50 to 60 younger ones in the 
boulevards), and also during a tour in the north of France this summer 
(where he found the promenades of elms equally ravaged by the scolyti at 
Dunkirk, Calais, Boulogne sur Mer, Montreuil, Rouen, Havre de Grace, Caen, 
St. Lo, Granville, &c.), seen hundreds of young trees in that incipient 
state of decay indicated by M. Audouin as arising from the attacks of the 
scolyti simply for food; and great numbers of these in which the females, 
having found them sufficiently debilitated, had deposited their eggs, and given 
birth to numerous broods of larvae, which had caused them to be either dead 
or fast dying. _ 
It is scarcely possible to overvalue, in an economical point of view, the 
importance of M. Audouin’s discovery, which, if it had been formerly known 
and acted upon, might have saved the greater part of the fine elms in the 
promenades in many of the principal cities in the north of Europe, which have 
fallen victims to the ravages of Scolytus destrictor, as well as 50,000 young 
oaks in the Bois de Vincennes, near Paris, which it has been recently necessary 
to cut down in consequence of the attacks of another insect of the same tribe, 
S. pygmze‘us. The practical directions to which it leads, in all cases where 
there is reason to suspect the presence of scolyti, are very simple, and may 
be briefly expressed as follows : — 
1. The first thing to be done is, to pare away the exterior rough bark with 
a cooper’s spokeshave, or other convenient tool: this admits of a distinct 
inspection of the actual state of the trees, which, if there is no trace in the 
inner bark either of small holes in old trees, or of those superficial furrows 
which the scolyti make for food in young trees (and which may be distin- 
guished from the natural crevices in the bark by their dark-coloured and dead 
margins), may be pronounced to be in a sound and healthy state, and requiring 
no further attention. 
2. If the inner bark exhibits either of the appearances just mentioned, the 
next thing to be ascertained is, whether the female has already deposited her 
eggs in it, and if it contain the larve of the scolyti: to know which, it is 
necessary to cut away portions here and there of the bark down to the actual 
wood, and examine them; and, if the existence of larve be proved, the 
trees should be cut down, and their bark peeled off, and every fragment of it 
carefully burnt. 
3. Those trees which, though pierced with exterior superficial holes or 
furrows, have no larve in them, are such as have been attacked by the scolyti 
for food only ; and, if they be carefully brushed over with coal tar, the smell of 
which is highly offensive to the perfect scolyti, there is every probability that 
they will be secure from the future attacks of the females; and that the 
repetition of the same process in the spring, for a year or two, would enable 
them to resume their vigour, and to become healthy trees ; for the future fate 
of which, if, at the same time, the entire removal of all the trees actually diseased 
has been attended to, there would be no need for apprehension. It is in this 
way, as we are informed by Mr. Spence, that a great number of the young elm 
trees in the boulevards at Brussels, brought into an incipient stage of debility 
by the attacks of the scolyti for food, but not yet attacked by the females, 
were treated in the spring of 1836 with every prospect of a successful result ; 
though, of course, some years must elapse before any absolute deductions can 
be drawn from the experiment. The above most important information was 
communicated to us by Mr. Spence in December, 1836. 
Recorded Elms. Evelyn, to prove that the elm attains “a prodigious growth 
in less than a person’s age,” mentions a tree which he had seen, “ planted by 
the hand of a countess, living not long since, which was near 12 ft. in compass, 
and of a height proportionable.’ He mentions elms, “ now standing in good 
numbers which will bear almost 3 ft. square for more than 40ft. in height.” 
