AGIUCULTI^RAI. AIMMtdlMllATION 1111, I^ MrJ4. 313 



action on tli«' plant. 'V\w loud arid iiia;^iiosiutn have a jjrral jlcal l<» 

 <l() with it. an<l it is rathrr (liflicult to sny a poison will hnrn on<» plant 

 h(MHUs(> it has hiirru'd some other plant. 



The hcan is supposed to In* more lender to arsenirals tlinn n pi-ni h , 

 hilt as far as Mia<;nesiuni is eoneerned it is more hardy. 



Wo have made arranjjements to havo magnesium arsenate tester! 

 under all conditions this year in the West and North, and should have 

 some* additional information on this point soon. 



Ma<;nesium arsemite is only manufactured hy one company, and 

 it is (louhtfid if a stahle formula has l)oen developed. Tliis work 

 re(|uires many tests in different districts in order to he certain of 

 inse<"t control without plant injury. 



The insecticide |)hase of the (piestion is still larjij«'ly unsolved. A 

 man was sent to Mexico this year to continue investifjations of 

 parasites, and he ('(dhn-ted and slnpped a hirf:^e numher of the |)arasites 

 of the Mexican heun hcelli' from near Mexico City. Ahout ;i, ()()() of 

 these heneficial insects have been received and an attempt will he 

 made to colonize them next year. It is still too earlv to predict 

 results. This material was carefully watched and nil secondarv 

 parasites were destroyed. 



Mr. Graf. wSecondary parasites are the ones that kill the beneficial 

 parasites. 



Mr. Andkrson. .Vre the infestations on the edges of this center 

 as heavy as they were in Birmingham? 



Mr. Graf. Yes, sir. One of the most noticeable things is that 

 the most complaints come in from the north boundary of the insects. 

 As it goes further north it is becoming more injurious. 



Another thing is the infestations along the southern edge is becom- 

 ing weaker, but whether it is the level country, the absence of hills 

 for hibernating the insect, or whether the climate is not suitable, is 

 something we can not tell. 



Doctor Howard. Does it fly away to a distance to hibernate ? 



Mr. Graf. In New Mexico, it was found in the woods 7\ miles 

 from the nearest beans, and that is as far as w^e looked. T would 

 say 20 to 40 miles would be within easy reach. 



Mr. Anderson. Does it attack anything except beans? 



Mr. Graf. In the East it feeds on all cultivated beans, cowpeas, 

 soy beans, and other legumes, and to a limited extent on the flowering 

 beans, but it is a primaiy j)est only, as we think now, on cultivated 

 beans. 



Doctor Howard. Does it not affect the w^ild cucumber? 



Mr. Graf. Xo, sir; that is another insect. The insect is apparently 

 changing its habits a great deal. We thou<^ht we knew something 

 about it after it had been in here a year. We thought it would be 

 possible to grow early beans in Birmini;ham this year. The Italians 

 tried it the previous year and (piit. The beetle was two or three 

 weeks late last vear, and some of the people grew early beans suc- 

 cessfully. The Italians noted the success and tried to plant a verj' 

 large crop of beans slightly later and they were all destroyed. In 

 the fall it was expected the insect would be injurious until the 1st of 

 September, but it had disappeared from the fields on the 1st of 

 August, when the weather was very favorable for further develop- 

 ment. 



