102 



THE AGRICULTURAL NEWS. 



April 8, 1905. 



Disinfecting Cotton Seed. (Contd.) 



Mr. H. A. Ballou, the Entomologist, writes: — 



There are three pests, it seems to me, that could be 

 transported vith the seed, viz., the leaf-bli.ster mite, the 

 cotton worm, and the cotton stainer. 



The cotton worm is not likely to be transported in this 

 way for several reasons. So far as is known, the eggs of the 

 cotton worm are always laid on some green part of the cotton 

 plant. There would be no inducement to cateri)illars to 

 visit ginneries to infest cotton seed ; it is very likely that 

 if, by'"any chance, catcr[iillars were carried from the field 

 in the picked cotton, they would soon leave in search of more 

 suitalile food. 



The leaf-blister mite would i>robably not infest the .seed 

 or be carried with it, but as it is a very serious pest, precau- 

 tions should be taken to prevent its introduction into 

 localities where it does not occur. 



The cotton stainers, on the other hand, feed on the 

 cotton seed, and might be carried from one place to another 

 in or on the bags of seed. In the process of hand-iiicking, 

 however, it ought to be possible to get the seed quite free 

 from stainers. 



I)i/i<dc'rcus andivae occurs in Jamaica, St. Kitt's-Xevis, 

 Antigua, and ^lontserrat. Dysdernis amiuliijcr occurs in 

 Dominica, St. Lucia, Barbados, St. Vincent, Grenada and 

 the Grenadines, and a third species in Trinidad and Grenada. 

 It is important that none of these species should be intro- 

 duced into islands where they do not now occur. Although 

 Drjsdeirus anmdiger does occur in Barbados it is very rarely 

 found there and i.s not, at present, a pest. 



As a precautionary measure, I would suggest the 

 fumigation of all seed, imported to Barbados and St. Vincent 

 for planting, with carbon bisuli.hide at the rate of 1 B). 

 carbon bisulphide to every 1,000 cubic feet of space in the 

 box or bin. 



This would prevent the introduction of any of the pests 

 mentioned and sliould be used without fail in Barbados to 

 guard against the leaf-blister mite, and in St. Vincent to 

 guard against the cotton worm, and in other islands when 

 any danger exists of introducing any species of cotton 

 stainer to a new locality. 



The treatment with corrosive sublimate, 1 in 1,000, 

 would serve as a protection against those insects that attack 

 stored seeds ; corrosive sublimate is a violent poison and 

 .sufficient is left upon the seeds after the steeping and drying 

 to prove fatal to insects eating their way through the seed- 

 coats. But it could not, however, be depended on to .safe- 

 guard against the three kinds of pests mentioned above. For 

 ifhese fumigation would be necessary as already suggested. 



Cotton as a Catch Crop in St. Eitt's. 



To the Editor of the Aijrindtwal Kcirs. — 



Sir. — The figures and facts detailed below will, I trust, 

 prove of interest to your readers. 



For the .season of 1904-5 about 70 acres of well-tilled 

 sandy loam with free draining subsoil, belonging to two 

 estates with which I am connected situated on the leeward 

 side of the island of St. Kitt's, were planted with Sea Island 

 cotton. The sowing took place from May to July and the 

 reaping from October to February following. The iirevious 

 cane crop having been removed, the fields were ploughed and 

 cross-holed, but the cost of these processes is not charged 

 against the cotton as they were necessary for the subsequent 

 cane crc>p. 



The cotton reaped amounted to a little over 200 ft. lint 

 per acre. The actual charges per acre are given below, but 



the clearance is to some extent a matter of estimate, though 

 I submit that a selling price of Is. per K>., having regard 

 to the high character of the cotton, is a moderate 

 assumption. ' Ginning ' includes pres.sing, baling, and 

 material. 'Paris green' was api)lied pure, as its use 

 without lime was found cheaper and more effective. * 

 Cartage in the field and the supervision of the estate staff 

 are not charged, as the expense as against the estate was not 

 thereby practically increased. Half the cost of manure 

 (cattle and .sheep dung) for the next cane crop is charged 

 against the cotton, which is also charged with a final weeding 

 and re-crossholing for the same purpose. The land, if kept 

 for cane alone, would have been green-dressed or otherwise 

 manured ; the turning in of the cotton bush will partly 

 perform the function of a green dressing. The fields were 

 heavily attacked by the caterpillar but jn-actically free from 

 leaf-blister mite and black boll : the few plants with the leaf- 

 blister mite were pulled and burnt. The cotton seed was 

 crushed at the ginnery at the local rate and returned to 

 planters. 'Sorting' may in future cost rather more than 

 stated. 



Cost (if One Acre of Cotton <ind Estimated Clearance. 



£ s. d. 



m 



2 



3 



5 



10 



IG S 



1 3 



5 7 



9 



G 



Cost of .seed (Rivers' Sea Island imported) 



Planting 



Weedings (six) 



Paris green (pure) * 



Applying above 



Reaping 



Drying, etc. ... 



Sorting 



Cartage to ginnery 



Pulling and burying cotton bush and re-crossholing 2 6 



Final weeding ... ... ... 1 



^Manuring for cane crop (half cost) ... 15 



Ginning,''etc. (200 a. lint) ... ... 1 5 



Cartage to port ... ... ... 2 



Porterage ... ... ... ... 3 



Lighterage ... ... ... ... 4i 



Freight ... ... ... ... 5 4 



Charges in U.K. (Commission, discount, etc, 



say) ... ... ... ... 1 



Deduct value of 575 lb. cotton seed for 

 cattle food at Ic. per lb. 



A^alueof 200 lb. lint at U. 



Estimated clearance per acre 



£ 5 G 5 



£ 1 4 



£ 4 2 5 



£10 



£ 5 17 7 



I desire to emphasize the point that cotton is treated 

 here solely as a catch crop interposed between the principal 

 cane crops, that is, the cotton must be planted after the 

 removal of the cane and subsequent tillage — the 

 earlier the better — and be reaped before the following 

 cane replant is sufficiently advanced to sufiFer from the 

 competition of the cotton. Some other land, higher 

 and poorer with clay soil, was cropped with cotton 

 with wretched results : the experiment will not be repeated. 

 I would also observe that our good results were obviously 

 due, to a large extent, to careful cultivation. Some seem 



* The use of Paris green without lime is referred to in the 

 Wed luiliiii, Biilldia (Vol. Ill, p. .')28) and the A'jricuUural 

 A'.ir.s (Vol. Ill, p. 281). [Ed. A.N.] 



