JUL1519?': 



217 ^^f'ct,. 



Severin (H. C). Tenth Annual Report of the State Entomologist 

 of South Dakota for the Period ending 30th June 1919. — South 

 Dalota State Coll., Brookings, 15tli September 1919, pp. 1-36, 

 1 plate, 11 figs. [Received 26tli March 1920.] 



An account is given of the inspection of South Dakota nurseries with 

 a list of the pests found. Much information has been collected 

 with regard to the web-spinning sawfly of the plum, Neurotoma 

 inconspicua, Nort., and the common field cricket, Gryllus abbreviatus, 

 full details of which are to be pubhshed. 



Experiments show that there is practically no difference in the 

 efficacy of crude or refined powdered white arsenic when used in 

 poison-baits for grasshoppers. The time of apphcation is apparently 

 also immaterial. 



Special investigations have been made with regard to pests and 

 diseases of currants and gooseberries. Those dealt with include 

 a Longicorn beetle, Psenocerus supernotatifs. Say (American currant 

 borer), which attacks chiefly the old dead branches, but occasionally 

 injures healthy stems. The grubs tunnel lengthwise and several 

 may be found in one stem. They remain in the stem until the 

 following spring, when pupation occurs in the tunnel. The beetle 

 emerges in 2 to 4 weeks. There is one generation a year. The moth, 

 Aegeria (Sesia) tipuliformis, Clerck, is similar both as to life-cycle 

 and habits. The best remedial measures for both pests is to cut 

 out all dead wood as well as all stems 4 years old and over, close to 

 the crown of the plant, and burn before June. The same treatment 

 should be carried out with canes and fohage that are wilting or 

 becoming weak and sickly. 



The scale, Eulecanium {Lecanium) corni, Bch., has but one genera- 

 tion a year. The remedial measures advocated are spraying before 

 the buds open mth dormant strength lime-sulphur or kerosene emulsion 

 consisting of 1 part of stock to 4 or 5 parts of water. The usual 

 remedial measures are advocated for the oyster-shell scale, Lepidosaphes 

 idmi, L., and Aspidiotus ancylus, Putn. Myzus rihis L. (currant 

 aphis) infests the undersurface of the leaves, causing deformity and 

 discolouration. Hibernation occurs in the egg-stage on the canes ; 

 these give rise in the spring to the stem-mothers which migrate to the 

 leaves and give rise to several generations of parthenogenetic females. 

 The first spra}^ should be apphed when the buds are breaking, follow^ed 

 by a second in about 10 days and a third 14 days later. The sprays 

 advocated are : — 1 part Black-leaf 40, 1,000 parts of w^ater, with 

 soap at the rate of 1 lb. to 25 U.S. gals, of spray ; 1 lb. laundry soap to 

 5 U.S. gals, of water ; or 1 part of stock kerosene emulsion to 7 parts 

 of water. 



The sawfly, Pteromis ribesii. Scop., is the most destructive enemy 

 of the foliage of currants and gooseberries in South Dakota. The eggs 

 are laid in the spring on the undersurface of the leaves and hatch in 

 about 10 days. The larvae feed in colonies and eat small holes in the 

 leaves, eventually devouring the leaf-tissue. A bush may be defoHated 

 in a few days. After about three weeks the larvae hide under trash 

 or burrow into the ground ready for pupation. There are two genera- 

 tions a year, the second brood appearing about the time the ciurants 

 are ripening. The larvae hibernate in a cocoon. Lead arsenate paste 



(677) Wt.P1850, 163. 1,500. 6.20. B.&F.,Ltd. Gp.11/14. a 



