202 



THE AGRICULTURAL NEWS. 



June 



1908. 



INSECT NOTES. 



Poisoned Bait for Grasshoppers. 



Circular- No. S.ff of the Biireau of Ehtoiiiology of the 

 U.S. Department of Agriculture consists of an account, 

 written in popular language, of the life-history and 

 habits of two species of grasshoppers {Melancplus 

 ilifferentialisAniXM. hiriftaf as) that are responsible 

 for a large amount of devastation in alfalfa fields in the 

 States, as well as of methods for the destruction of these 

 pests. 



Although alfalfa is not a croj) of great importance 

 in tiie West Indies, grasshoppers are often troublesome 

 iiud sometimes serious pests. Readers of the Agrl- 

 cultwnd i\V((\s m-iV be interested in one of the remedies 

 given in the above-mentioned circular imder the 

 heading of ' Poisoned Baits ' : — 



What has come to be knnwn as tiie '( 'lidillc iiiixture' is 

 {giving most satislactory results in deiding with grasshopjiers 

 oil the ranches of both the I'liited States and Canada. The 

 iiiixturc is coniposod of half a barrel of fresh horse droppings 

 ill wliii-li is niixud a pouiid each of salt and I'aris green. If 

 tlie horse droiipings are not fresh tjie salt is^lissolved in wattT 

 and mixed with the manure and iioi.soii.^ "Wlien tlds mixtniv 

 is scattered freely about where tlie grassIioppiTs are abucdant 

 they seem to be attracted to it, for they devoiu- it readily and 

 are poisoned thereby. Dr. James Fletcher, Entomologist for 

 the ilomiuion of Canada, cites an instance where tins nii.x- 

 ture had been .scattered freely around the eilges of a ficlil, 

 and states that this particiil.u- field stooil out as a green patch 

 in a liiipwn plain, as it was situated in tlic midst of fields 

 where nothing had bei^u done to destroy the gi-assiiop|iers. 

 This 'Criddle mixture' now seems picferable to the poisom-d 

 bran rcmeily that has given, and .still continues to give, 

 beneficial results, for it is fess expensive than the latter and 

 Jess likely to poison otiicr animal life. 



from which the disease takes its name seldom occurs before 

 the final stags'bf the malady, patients at first mo.stly suffer- 

 ing from sleeplessness. There is no danger of such a patient 

 communicating the disease to others except where the district 

 is infested by stinging Hies. 



The means of averting the disease are — Kr.st, to avoid 

 the marshy places favoared by the insect ; secondly, the 

 destruction of the fly itself : thirdly, the protection of healthy 

 as well as infected jiersons from the sting ; fourthly, to 

 prevent the introduction of diseased persons into villages 

 that have escai)ed infection ; and fifthl}-, to transfer infected 

 villages to districts-wherc the tse-tsc Hy does not exist. For 

 the destruction' of the tly it is necessary to cut down the 

 lirushwood for about -oOO metres from the water and to 

 deprive the insect of its usual food — namely, the blood of 

 vertebrates, without which it cannot live for longer than 

 three days. The brushwood should be cut down, or better 

 still, burnt down at night, when the Hy does not sting. The 

 chrysalis dies when exfjosed to the sun, even under five 

 centimetres of earth. Europeans should make their camps 

 and houses at a distance from rivers and streams, and 

 sei)arate from those of the natives, who should be warned to 

 draw their supplies of water only at night, when the fly 

 is inactive. The houses should be closed with wire gratings. 

 Infected persons should be isokited and treated with injec- 

 tions of atoxyl, a preparation of aisenic which causes the 

 disappearance of the parasites from the blood, at least for 

 a time. The.se injections exercise a tonic effect upon the 

 ]iatient. In general it is not necessary to inject more than 

 .^0 centigrammes of atoxyl in small doses frequently repeated. 



Sleeping Sickness and Its Prevention. 



Tile Fieiicli (."ohuii.d .Minister has caused the 

 4listribiition, throughout h'rench Afiica.of a document 

 dr^'.wii up by the Iiispector-Geru'ritr of the coloiual 

 saiiitarv service setting forth the measures to be 

 omployid for the prevention of sleeping sickness. The 

 following ci)ncise summary of the contents of this 

 document (taken from the Lcuidon Times of May 22) 

 mav be of interest, since it refers to a tro[)i(Ml disease 

 which has of late attracted a gtx)d deal of attention : — 



Tlie species of the tse-tse Hy known as (r'fos.iiiitt jmlpitlix 

 is perhaps the only one capable of transmitting the disea.se. 

 .Still, until more is known on the subject, there is reason to 

 regard all stinging insects as suspicious. 



The Hrst syinpt(nns of the disca.se arc a fever on which 

 (piinine has no effect, a swelling of the glands of the neck 

 and jaw, blotclies on the skin, and .severe ]iaiii following the 

 .slightest blow or even a pinching of the .skin. The sleep 



UTILIZATION OF POND MUD. 



Ponds frequently occur in corners of fields on 

 estates, and wdien these are being cleared out, the mud 

 taken IVoiii the bottom can frequently be utilized with 

 advantage, although the composition of the sediment 

 will n.-iturally depend upon the character of the 

 surrounding soil and the nature of the pond. 



Tlie coaipnsitinii of one or tw-o samples of mud from 

 ponds ill fjiglaiid, together with notes as to the uses of tiit- 

 material, were given in an article that appeared in a late 

 niiiiiber of the Jfnirnnl of the Hoard of .\grienlturc of (Jreat 

 I'.ritain. .\ sample taken from a pond at Kew contained 

 4.")do per cent, of moisture, 0"4;39 per cent, of nitrogen, 

 O'L'T |ier cciil. of |ihosphoric acid, 12'0-f per cent, of lime, 

 together with magnesia anil other alkalies, e(|ual to Oi)7 per 

 cent. A specimen of pond mud from Xottinghainsliirc con- 

 tained "S ,sl per cent, of moisture, O'SG-' per cent, of nitrogen, 

 (l-.'!"_' |icr cent, of phosphoric acid, and 7'79 per cent, of lime. 



\\'licrc a pond is situated at the lower end of a Held, it 

 is likely to receive, after rain, surface wa,shings wliidi may 

 possess considerable manurial value. On the <itlier hand, if 

 the pond is one formed by springs, the sediincnt may be of 

 little or no value. 



.\t Kew the pond mud is used for general gardening 

 |iur|iose.s, ami as a mulch for beds, boider.s, and trees. It has 

 also given good results as a to|i dressing for grass. Before 

 use. the water >liould be allowed to drain away, and the mud 

 broken up. 



It is pointed out that the eflect of such material is a.s 

 iiincli of a mechanical as of a chemical nature, and if used on 

 land of a lighter or drier texture, would assist in improving 

 its physical con.litiim. On heavy land it [irobably wxadd not 

 be .so successful. 



