122 



THE AGRICULTURAL NEWS. 



April 21, 191' 



INSECT NOTES. 



THE SPREAD OF THE PINK BOLL 

 WORM. 



In the current number of the Journal of Economic 

 Entomoloyy there is a notice to the efiFect that last Xovember 

 specimens of cotton bolls showing the presence of GeUchia 

 gossypiella were received at the Bureau of Entomology in 

 Washington from San Pedro de las Colonia.-, Mexico. This 

 is the first time that this important pest has been recorded 

 from America, and investigation.^ indicate that it was 

 introduced into Mexico in cotton seed imported from Egypt 

 for experimental purposes. In order to safeguard the 

 country against further danter from the pink boll worm an 

 absolute quarantine was immediately placed on Mexican 

 cotton seed and bales of lint. Further, all .shipments of 

 Mexican cotton seed which have entered the United States 

 since last July have been traced to their destinations and 

 steps are being taken to have this seed cru.shed without delav. 

 It is fortunate, however, that most of this imported seed was 

 more than a year old and would therefore be free from 

 infestation. This pest has probably been established in the 

 Lagune District of Mexico for two or three years, but ha.? 

 apparently only spread extensively during the last year, and 

 so far it has not been discovered in any of the seed brought 

 into Texas. 



It will be seen from this that the cotton crop of the 

 Southern States is threatened with a very serious danger, 

 and unless the pink boll worm can be exterminated by 

 co-operative work between the Ignited States and Mexican 

 authorities, its ultimate infestation of the cotton fields of the 

 Southern States is a practical certainty. 



This insect has been mentioned in former numbers of 

 the AaricidtM-al News, and an account of its life-history, 

 habits, etc., was given in Vol. XIV, No. 346 so that it is not 

 proposed to go into these in detail again, but it may be of 

 interest to recall the distribution of this pest and the way 

 in which it has spread. 



A little more than ten years ago (1906) the pink 

 boll worm was known only in the cotton-growing countries of 

 Asia, but three years later (1909) it had spread to East Africa, 

 and by 1914 it was recorded from India, Ceylon, Burmah, 

 Straits Settlenient.s, Egypt, British and German East 

 Africa, Nigeria, Sierra Leone and the Hawaiian Islands. At 

 the present time it is probable that this insect extends 

 throughout the cotton-growing countries of Asia and Africa, 

 and has lately become established in a district of Mexico. 



HOW THE PEST sPKEADS. 



The larvae, that is the pink boll worms themselves, 

 besides attacking the unripe cotton .seed in the growing boll, 

 are also found in seed in old dried bolls, in seed shipped for 

 planting or oil extraction, and even In the seed which gets 

 into baled cotton. The duration of the larval stage is 

 usually about three weeks, but records show that this can 

 be prolonged to such an extent that it would be possible for 

 the larvae to survive even the most distant journeys. The 



pupal stage is often passed inside the shell of the seed which 

 has been excavated by the larva, so that the period of spread 

 is still further lengthened. 



The pink boll worm has on several occasions been inter- 

 cepted in shipments of cotton seed in the I'nited States 

 and up to the present time it has not become established in 

 that country. The following instances taken from the 

 Journal of Economic EntoiiLology will show that there is 

 a constant danger of its entering a new country under 

 unusual conditions. 



On one occasion some 'dead larvae of Gelechia gossypieUa 

 were found in samples of China cotton enclosed in glass 

 trays exhibited at the Panama- Pacific Exposition at San 

 Francisco. Although every precaution was taken to safe- 

 guard this material by the California authorities, the finding 

 of these dead larvae forcibly demonstrates the possibility of 

 introducing new and injurious pests in plant products exhi- 

 bited at Expositions. 



'In this connexion it is of peculiar interest to note that 

 the prize ship Appam which was brought into Hampton 

 Roads (Virginia) early in the year (1916), contained as 

 a part of^ its cargo some 200 tons of cotton seed from 

 Lagos, West Africa, a region known to harbor the pink 

 boll wi:>rm. Although no living larvae of the pink boll worm 

 were located, it was apparent from the condition of the 

 material that about 2 per cent, of the seed had at one time 

 been infested with this insect." It is further stated that as 

 a precautionary measure the entire shipment of cotton seed 

 was converted into fertilizer, and the dock on which the 

 seed had been unloaded was thoroughly cleaned and the ship 

 fumigated with hydrocyanic acid gas. 



Now that the pink boll worm has gained an entrance 

 into Mexico, it would seem that the strictest quarantine 

 measures and the most rigid inspection will be necessary 

 in order to prevent the spread <>f thi.s pest to the cotton 

 district of the Americas and the West Indies. Until the pro- 

 cesses for treating cotton seed (mentioned below) have been 

 perfected, and until these or similar measures of control have 

 been generally adopted in the countries infested with this 

 pest, it is strongly urged, as has been suggested in a former 

 number of the A</ricuUural Xens that a prohibition be 

 placed on the importation of all cotton-seed from infested 

 countries into those West Indian islands where a cotton 

 industry exists This would not be such a hardship as 

 might at first appear, since the various cotton-growing islands 

 in the West Indies have well-developed strains of fine cotton, 

 and the importation of .seed for planting isjtherefore unneces- 

 sary. Such cotton .seed as may be imported for oil extraction 

 should be admitted only if it comes from a district known to 

 be free from the pink boll worm, and even then under 

 strict regulations. 



I 



CONTROL WORK AGAINST THE PINK 

 BOLL WORM IN EGYPT. 



For the last four or five yeais since the pink boll worm 

 began to be a serious pest in Egypt, experiments have been in 

 progress to find out some means of controlling the insect not 

 only in the growing cotton, but also in the picked cotton seed, 

 and in the old dried up bolls left on the cotton sticks after 

 the crop and subsequently stacked for fuel. These mea.«ures 

 of control are all more or less in the experimental stage, but 

 it may be of interest to refer to the more important of those 

 that have been mentioned in the Agricultural Journal of 

 Egypt from time to time. 



The recent work of the Government Experimental 

 Farm has shown that the damage done to the growing bolls 

 by this insect can be materially lessened by an earlier 



