'nil'; AioN'i'iii.v Mi'i>iii';'riN'. 221 



NOTES FROM THE COUNTY COMMISSIONERS. 



By Geo. P. Weldon, Chief Deputy State Commissioner of Horticulture. 



Report of State Board of Horticultural Examiners. 



Since the last report Ihe following iiieii liaxc (|ualifi('(l foi* the [)osilioii 

 of coiiiily liofi ieiilt ural coiuiiiissioner in llif coiinlies named: 



Sacramento — San Joaquin — 



Fvril ('. 1! rosins !•:. K. WoHv 



U. M. r.olonir Il.irry Ladd 



li. Ij. (jil)l)oi)s AVillinin (Jardcii 



Howard K(>rclii\ a! It. ('. Tuhbs 



Ventura — Monterey — 



n. S. Vaile .1. P.. llickinaii 



A. A. Block .V. W. Tate. Jr. 



J. X. Flench Alameda — 



Santa Barbara — Fred Senli)ei-m'r 



('. W. liccrs I>. 1'. Macdonald 



A. J. Cook, 

 Tiios. F. Hunt, 

 II.VKRY S. Smith. 



Stale l>oai-(| of 1 lorl icnltural E.xaiiiiiiefs. 



NOTES ON WALNUT APHIS CONTROL. 



liy n. y. \'ailk. County Conuuissioner of rioiticulture, Ventura County, Califoinia. 



For several years past a luiniher of our orehardists liave felt that tlie 

 walnut aphis, Chromaphis juglandicola, has been of considerahle dam- 

 age to the Avalnut vyo\\ throughout southern California. Very early 

 in the season this pest Iteeoiues nuuiei-ous on the leaves and also on the 

 nuts as they are just setting. Soon a large amount of honey dew is 

 secreted, following which the sooty fiuigus coats the leaves and fi-uit 

 with a very heavy black covering, which must of necessity choke the 

 respiration of the tree to a large extent. Frecjuently leaves droop and 

 even fall to the ground in large numbers early in the season, before the 

 crop is half matured, because of this pest. It would seem that this 

 must largely lessen the percentage of juits which reach No. 1 size. 



For the past four years, to the writer's knowledge, this office has 

 endeavored to assist in the control of the walnut aphis through the 

 liberation of ladybird beetles in a certain limited section of Ventura 

 County. Both the Hippodamia convfrcjina and the OUa ahdominalis 

 have been used to (juite an extent. The former has not proven very 

 successful as a tree climber, and usually leaves the walnut for other 

 things before the end of the season. The latter is native in the county 

 and very frequently does effective work on individual trees. Eggs of 

 both species may be found this season in almost all ])arts of the county 

 on walnut trees. So far, however, the control by this method has proven 

 unsatisfactory, and is hardly to be recommended as worthy of trial. 



Last season the State C^niversity tried some experinients agaiiist tiie 

 walnut blight with various sprays, and with high power spray outfits 

 and nozzles. This is probalily the most thorough spraying work that 



