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Lathrop (F. H.) & Black (A. B.). The Western Peach and Prune 

 Root Borer {Sanninoidea opalescens, Edw.). — 3rd Crop Pest & 

 Hortic. Rept., 1915-20, Oregon Agric. Expt. Sta.. Corvallis, 

 10th January 1921, pp. 59-70, 1 plate. 



Aegeria (Sanninoidea) opalescens, Edw. (western peach and prune 

 root borer) is the most serious pest of prunes in Oregon. It is probably 

 a native moth, and greatly resembles in life and habits the eastern 

 peach-tree borer [S. exitiosa]. Several kinds of stone fruits are attacked, 

 almonds, peach, apricot, and prune being preferred. Hibernation 

 occurs in the larval stage, the larvae being more or less active during 

 warm periods, and leaving their tunnels in the bark for the gum and 

 frass around the base of the tree. With the approach of spring they 

 become more active and spin cocoons, from which adults emerge 

 during the latter half of June. Oviposition begins about 1st July, 

 unhealthy trees being preferred, though healthy trees also are fre- 

 quently attacked. Each female produces from 300 to 800 eggs ; these 

 hatch within ten days, the young larvae tunnelling in the bark, and 

 later in the inner bark and cambmm. There is only one generation 

 in a year, but owing to the extended oviposition period, larvae of all 

 sizes may be found in the tree at almost any season. 



Many larvae fail to mature, disease attacking a large percentage. 

 A parasite, Itamoplex tejonensis, destroys about three per cent, of the 

 pupae. Many experiments in artificial control, carried out during 

 1916-20, are recorded in detail. The old method of digging the larvae 

 from their tunnels is the most reliable yet known ; this should be 

 done before 1st July and in autumn after 1st September. Applications 

 of asphaltum, tanglefoot, etc., to the base of the tree are not recom- 

 mended. Tree protectors, when properly applied, give good results, 

 but are not recommended, as they are apt to stimulate root rot. 

 Whitewash treatments have been found beneficial, a successful formula 

 being 8 lb. quickhme, \ lb. lead arsenate powder, 2 lb. salt, \ lb. glue, 

 2 oz. 40 per cent, nicotine sulphate, and enough water to make into 

 a thick paint. The soil should be removed from the base of the tree 

 to a depth of 3 or 4 inches. The crown of the tree should be dried 

 and brushed, and then the wash applied with a stiff brush, coating 

 the trunk to a height of 14 to 16 inches. The soil should then be 

 replaced. The first application should be made immediately before 

 1st Juh', and another should be given in mid- August if necessary. 

 Naphthaline washes gave very good results in 1920, but this treatment 

 cannot be recommended until more is known about its effect on the 

 tree as well as its efficacy. Further investigations will be made, and 

 these recommendations are not regarded as final. 



Childs (L.) & LcnETT (A. L.). Improved Sprays and Practices in 

 Codling Moth Control.— .3;'i Crop Pest & Hortic. Rept., 1915-20, 

 Oregon Agric. Expt. Sta., Corvallis, 10th January 1921, pp. 71-81, 

 4 plates. 



This paper correlates the results of recent investigations into 

 improved methods of control of codling moth [Cydia pofnonella]. 

 The bulk of the information has been previous^ noticed [R.A.E., 

 A, viii, 372, 462]. 



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