335 



Britton (W. E.) & Zappe (M. P.). An Outbreak of the Arbor-vitae 

 Leaf Miner, Argyresthia thuiella, Packard. — Conn. Agric. Expt. 

 Sta., New Haven, Bull. 234, 1922, pp. 157-160, 3 plates. 



During the outbreak of Argyresthia thuiella. Pack., on arbor-vitae 

 trees in Connecticut the injury was very severe, in some cases almost 

 all the chlorophyll being destroyed. Hibernation apparently occurs 

 in the larval stage in the leaf-mines. Pupation takes place early in 

 Ma}^ and the adults begin to emerge about 20th May. The first eggs 

 were found on the 9th June, by the 21st June they had hatched, and the 

 young larvae were mining the leaves. They enter the leaves under 

 the edge of the base next the twig, and make mines between the upper 

 and lower epidermal layers. Parasites of this moth that have been 

 bred in Connecticut are the Chalcid, Pentacnemus bucculatricis. How., 

 and the Braconid, Apanteles hedelliae, Vier. Spraying experiments 

 were carried out with the following insecticides : Lead arsenate, lime- 

 sulphur, Scalecide, kero-spray, fish-oil emulsion, carbolic acid emulsion 

 and nicotine sulphate. All the trees treated with these insecticides 

 had their usual treatment of nicotine and soap a week later. With 

 the exception of carbolic acid and lead arsenate two applications were 

 made, one 24th May and the other 4th June. Counts were made in the 

 autumn of the larvae in the leaves of the younger trees. The results 

 were inconclusive. 



Zappe (M. P.). Tests of Materials for the Control of Wireworms. — 



Conn. Agric. Expt. Sta., New Haven, Bull. 234, 1922, pp. 163-165. 



The substances tested were turpentine emulsion, fish-oil emulsion, 

 carbolic acid emulsion, gum-camphor mixture and naphthaline flakes. 

 The method adopted is described. Apparently none of these remedies 

 was of any value. 



Britton (W. E.), Zappe (M. P.) & Stoddard (E. M.). Experiments 

 in Dusting versus Spraying on Apples and Peaches in Connecticut 



in 1^21.— Conn. Agric. Expt. Sta., New Haven. Bull. 235, 

 February 1922, pp. ^^209-226, 6 plates, 3 figs. 



Experiments in the relative value of liquid and dust sprays were 

 conducted in Connecticut in four apple and two peach orchards. In 

 each case two treatments were given after blossoming on apples and 

 three on peaches. In the apple orchards the chief pests were codling 

 moth [Cydia pomonella], plum curculio [Conotrachelus nenuphar^, 

 apple maggot [Rhagoletis pomonella], false apple red-bug [Lygidea 

 mendax], and Aphids, as well as various chewing insects. The dusts 

 used were sulphur-lead, sulphur-lead-nicotine, and Sanders' dust. The 

 liquid spray contained liquid lime-sulphur, lead arsenate and nicotine 

 sulphate. In nearly all cases the best apples were obtained from 

 the spra3''ed plots. Both spray and dust gave good results against 

 C . pomonella and other chewing insects ; neither controlled the curculio. 

 The spray was more effective against fungi. 



On peaches the chief pests were curculio and fungous diseases. 

 The only spray used was atomic sulphur, and the dusts were sulphur 

 and sulphur-lime-lead arsenate dust. The dusted plots gave shghtly 

 better fruit than the sprayed plots. At present dusting is more costly 

 than spra\ang in both peach and apple orchards. 



