THE IRRIGATION AGE. 



375 



WARNING AGAINST DANGEROUS POTATO 

 TUBER MOTH. 



U. S. Department of Agriculture Issues Important 



Instructions Designed to Save Potato Crop in 



Many Sections of the United States 



Many Potato Growers Abandoning 



Raising of Potatoes. 



The potato Tuber Moth is working such injury 

 to potato crops in various parts of the country, es- 

 pecially in California and Texas, that the Bureau 

 of Entomology of the U. S. Department of Agri- 

 culture has issued a special warning and instruc- 

 tions to potato growers to help them overcome this 

 highly injurious pest. According to the specialists 

 this moth is being rapidly spread over the country 

 in shipments of infested potatoes and by careless 

 methods of using and distributing seed potatoes. 

 The warning is issued at this time in order to en- 

 able farmers to take special action with the seed 

 they will use for the fall crop. 



The Department particularly urges potato 

 growers to sort the potatoes for seed two weeks 

 after digging and then to sort them over two weeks 

 later. The tubers unaffected by the tuber moth 

 should then be placed in a moth-proof bin. It is 

 easy to pick out the infested tubers because of the 

 excrement of the moth, which adheres by means of 

 a web to the outside of the potatoes and can be 

 easily detected. 



The tubers placed in the moth-proof bin, after 

 final sorting, should then be fumigated by means of 

 carbon bisulphid (or bisulphid of carbon as it is 

 also known), in order to kill any moths which 

 might have bred out or have slipped in through 

 crevices, and when the bin was opened. Carbon 

 bisulphid is applied by pouring small quantities 

 into flat vessels such as milk pans or pie tins. An 

 average of 3 pounds should be used in 1,000 cubic 

 feet of space. It is more effective at high tempera- 

 tures, 80 to 90 Fahr., being best. About a pint is 

 poured into each receptacle and the pans are placed 

 in the bins at the top. The gas being heavier than 

 air naturally penetrates the mass of potatoes, reach- 

 ing those at the bottom. The bin should be tightly 

 closed for from 24 to 36 hours with good assurance 

 that the germinating power of the seed is not de- 

 stroyed. The utmost care should be taken that no 

 fire, such as that from a cigar, electric fan, stove, 

 or even a gas light or lamp should be brought into 

 the vicinity. Otherwise, as the gas is very inflam- 

 mable a fire may result or a serious explosion may 

 follow. 



All potato growers should keep a careful "look- 

 out" after fumigation. At first the fumigated seed 

 potatoes should be inspected daily to detect any 

 growth of the insect ; later, observation every other 

 day and finally once a week should be sufficient. If 

 there is any indication that the tuber moth is prop- 

 agating, a second fumigation with carbon bisulphid 

 should be given. 



This method of saving seed potatoes is so sim- 

 ple, although very effective, that the specialists fear 

 that many potato growers will disregard it. 



In order to grow fall potatoes, the government 

 points out that it is necessary for farmers to work 

 overtime on a cleaning up campaign, which should 

 begin at once on receipt of this special notice. Small 

 and useless tubers and tops should be promptly 

 cleaned up and burned. The land should be har- 

 rowed to break up the clods and leave as few hiding 

 places as possible for the moths. For the same rea- 

 son all weeds and all plants of the potato kind, such 

 as nightshade, ground cherries and similar weeds, 

 should be destroyed over large areas surrounding 

 the potato field. The Department urges growers of 

 potatoes to cooperate in this general work and thus 

 lessen importantly the numbers of the moths and 

 reduce their chances for propagation. It is believed 

 that if general cooperation can be secured it will be 

 possible to stamp out this insect pest. Any slipshod 

 method of raising potatoes at this present time is 

 regarded as particularly dangerous because of this 

 moth, and the specialists urge growers in infested 

 districts to choose some other crop rather than to 

 raise potatoes in a careless manner. Unless pro- 

 tective and defensive measures are adopted at once 

 there will be a serious reduction of the potato crop. 



McARTHUR BROS. AWARDED CONTRACT 



MacArthur Brothers Company, contractors, of New 

 York, have been awarded the contract by the United States 

 Government for the construction of the Sun River Irri- 

 gation Project in Montana. Upon submission of the bids, 

 about May 1st, the Interior Department caused a thor- 

 ough investigation to be made of the Sun River Project 

 before fully determining whether the same should be com- 

 pleted, and the department finally decided in favor of its 

 completion. The Sun River Diversion Dam is now under 

 construction by Government force account. 



The present contract awarded will complete the project 

 and consists of the construction of about 45 miles of main 

 canal and several small tunnels aggregating about three- 

 quarters of a mile in length, the cost of which will aggre- 

 gate about $900.000. This canal will have a capacity of 

 1,700 acre feet per day, and will have a width of 27 feet, 

 a water depth of 11 feet and a top width of 69 feet. All 

 the engineering details were arranged by Mr. H. M. Sav- 

 age, supervising engineer, for the Government. 



MacArthur Brothers Company expect to sublet a large 

 portion of this work and have opened a temporary office 

 at Great Falls, Montana, and subsequently will probably 

 open a permanent office at Gilman, Montana. 



Cedarville, N. J., August 12, 1913. 

 Mr. D. H. Anderson, 



Chicago, 111. 

 My Dear Sir: 



I am a subscriber to THE IRRIGATION AGE and get much 

 valuable information from it in each issue, but I am espe- 

 cially interested at present in getting all the information I 

 can secure regarding "Overhead Irrigation." I never find 

 anything in your magazine concerning that form of irrigat- 

 ing. Will you kindly tell me if you know of any maga- 

 zine published dealing mostly with that kind of irrigating; 

 also give me list of books on the subject and where I 

 can obtain them and the names of firms who have the dif- 

 ferent overhead systems for sale. 



Thanking you very much for this information in ad- 

 vance, I am 



Very truly yours, 



L. M. OGDEN. 



Send $1.00 for 1 year's subscription to the IRRIGA- 

 TION AGE and bound copy of THE PRIMER OF IRRIGA- 

 TION. If you desire a copy of The Primer of Hy- 

 draulics add $2.50 to above price. 



