171 
v 
ARTIFICIAL 
REMEDIES. 
Topical Applications to the Foliage. 
^ ® first account of the Colaspis larvae, in his third 
ort, he says: “The only way to prevent the ravages of the worm 
;ch we yet know of, is so to protect newly set plants that the 
ties will not get access to them. I have had no opportunity to 
m experiments, but it may turn out that some application to the 
and or to the plant, such as ashes, soot, lime, or salt, will ward 
the perfect beetle. The same remedies used in killing the Colo- 
3 Potato-beetle would also kill this species.” 
l discussing the Paria root-worms, Prof. Cook remarks: “I feel 
am that either Paris green or London purple would certainly 
uoy the beetles, if applied to the plants as we apply them to 
;roy the potato beetle or canker worm.” 
rom Prof. Burrill, of the Industrial University, I learn that a 
u s ^ raw ^ er . lies 011 ^ ie University grounds was attacked 
’.he beetles of Paria aterrima , that the leaves were dusted with 
■S. green, and that the beetles immediately disappeared, no fur- 
mjury being done to the vines. There is good reason to sup- 
t, consequently, that this remedy would prove effective, as far as 
adult beetles of all these species are concerned, and would thus 
f6 a check, at least, upon the increase of the larvae. Such appli- 
ms would of course not be permissible during the fruiting sea- 
- and, foitunately, the adults of none of these species emerge 
1 after the berries are picked. 
hether it is their usual habit to remain in the fields until after 
• e gg s are laid, escaping to other situations and resorting to 
r food plants only after this indispensable office has been per¬ 
ked, is a point of importance upon which we have as 'yet no 
j vledge. Fruit growers are agreed, however, as far as my in- 
tation goes, that the root-worms spread usually from old fields 
ew somewhat slowly, as if by a gradual progression from side 
de; and if this be true, it is altogether likely that the common 
i o of all the species is to lay their eggs before dispersing gener- 
j and the practice of poisoning the adults in the field will be 
Y effective as against the root-worms themselves, 
i e time when the poison is to be applied will of course depend 
ly upon the species by which the field is infested. If all three 
iresent, it will be absolutely necessary that several repetitions 
e treatment should be had, beginning in June, when the Scelo- 
is are emerging, and continuing until August, when Paria comes 
. If Colaspis only is present in the field, July will be the proper 
to poison the plants* *. There is a bare possibility that the 
s and ground might be sprinkled with substances which should 
I to repel the adults in search of places for the deposit of their 
I and Prof. Piley has thought it worth while to suggest ashes, 
lime, or salt, for this purpose ; but there is extremely little genuine 
1 'imental evidence of the effectiveness of measures of this class. 
he arsenical poisons are now so well understood that it is hardly necessary to re- 
w , arnir y against their excessive use. They serve their purpose 
i I; utle , d i Wlth i?ust or plaster, or suspended in large quantities of water; but even 
ley should not be used on the same ground year after year, without occasional 
* oi crops. 
i 
