THE MONTHLY BULLETIN 



CALIFORNIA STATE COMMISSION OF HORTICULTURE 



DEVOTED TO HORTICULTURE IN ITS BROADEST SENSE, WITH SPECIAL 

 REFERENCE TO PLANT DISEASES, INSECT PESTS, AND 

 THEIR CONTROL. 



Sent free to all citizens of the State of California. Offered in exchange for bulletins 

 of the Federal Government and experiment stations, entomological and mycological 

 journals, agricultural and horticultural papers, botanical and other publications Of a 

 similar nature. 



A. J. Cook, State Commissioner of Horticulture Censor 



E. J. VosLER, Secretary State Commission of Horticulture Editor 



ASSOCIATE EDITORS. 



Geo. p. Weldon Chief Deputy Commissioner 



Harry S. Smith Superintendent State Insectary 



Frederick Maskew Chief Deputy Quarantine Officer 



Entered as second class matter December 29, 1911, at the post office at Sacramento, 

 California, under the act of July 16, 1894. 



Simply a Matter of Record. — At the State Fruit Growers' Con- 

 vention recently held at Stanford University, an incident, which in the 

 opinion of the Horticultural Quarantine Division of the State of Cali- 

 fornia is of such prime importance as to warrant an official record of 

 the occurrence, was the statement — voluntarily made by an official of the 

 Idaho Potato Growers' Association — to the effect that this association 

 had, during one season in the past, imported from California into the 

 State of Idaho approximately 150,000 old gunny sacks, which had previ- 

 ously been used for holding and storing California grown potatoes ; had 

 distributed the same throughout the potato growing regions of Idaho 

 and used them for sacking the potato crop grown in that state. The 

 significance of this action is to be found in the two following facts: 

 First, that one of the most direct ways of introducing the potato tuber 

 moth into new territories is through the medium of old sacks from 

 infested regions, and second, that on February 7, 1914, the State of 

 Idaho issued a quarantine order forbidding the entrance into that state 

 of all Irish potatoes (Solanum tuberosum) grown in the State of Cali- 

 fornia for the express purpose of keeping the potato tuber moth {Phthor- 

 imcea operculella) out of the State of Idaho. — F. M. 



Who, When, and What? — The great discoveries of the world in- 

 terest all of us, and we are all keen to know when and by whom the 

 knowledge came. One of these discoveries concerns the most important 

 and most costly soil element — nitrogen. Though several great scientists 

 bad to do with the investigations that explained the formation of soil 

 nitrogen, Liebig in the middle of the last century suggested the accumu- 

 lation of ammonia and the nitrates in the soil, but the exact method of 

 their formation was still a sealed book. Pasteur's memorable researches 

 on the relation of micro-organisms to fermentation led him to suggest 

 fifty years later that nitrification in the soil was due to these micro- 

 organisms. A little later Schloesing and Muntz proved Pasteur's con- 



