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Oriental Fruit Moth Parasite s 



It should always be kept in mind that the work on biological control 

 of the Oriental Fruit Moth is still more or less in its infancy and there 

 are many points on which more information is needed becausu of the many fac- 

 tors, both climatic and entomological, which influence the effectiveness of 

 parasite libercition. 



On thu basis of our present inf orra..tion, investigators hc.ve cone to 

 believe that tho number of tiacrocontrus parasites should be in th<^ r-^tio of 

 approximately one colony of 250 parasites to 300 trees, in ordur to be ef- 

 fective the first year after liberation. Duo to the fact that there are 

 neither sufficient funds nor personnel available to provide enough parasites 

 to distribute to all of tne peach orchards in tne otate on this basis, an 

 attempt has been made to introduce the species into as many orchards as pos- 

 sible in the hope that once it is able to establish itself, the addition of 

 a limited number of parasites each year will supply a surplus at tne most ef- 

 fective period to give maximum control of the Fruit Moth. 



h- I. Bourne 



Leather Waste as a Fert ilizer Material 



J. N. liver son of tho Agronomy Department submits the follov/ing in- 

 teresting facts about leather dust and leather scrap. "During the process 

 of tanning leather, either chrome or tannic acid method is used. The pro- 

 tain material in the original hide is rendered impervious to the action of 

 water, and bacteria act upon it very slov/ly. This means that such sub- 

 stances as leather dust and leather scrup will remain in the soil for years 

 without giving appreciable amounts of nitrogen for plant use. Numerous 

 states have as a basic part of the fv^rtilizer law a st^.tement that leather 

 scrap or untreated leather shall not be used, and that the presence of tan- 

 nic acid will be prima facie evidence that l^^ather was used. If tannic 

 acid is found in the fertilizer, the whole lot is subject to confiscation. 

 I might refer you to the fertilizer lav; of the Stiite of Indiana .^s a typical 

 oxumple of such laws. You m-^y get this law by writing, as I have no copy 

 of it at present. Simil.^r lavi^s are found in the st-.tutes of Arkansas, 

 Missouri, Louisiana <:.nd Tennessee. 



"In using leather for fertilizer purposes, the fertilizer manufac- 

 turer usos two processes of treatment, either he steams thu leather or 

 treats it with sulphuric acid, in either case rendering the nitrogen nearly 

 as avuiliible as the nitrogen from dried blood." 



ji^ffect o f S ulfur on Le af Activity 



This subject is covered in an article by N. F. Childers in the April 

 issue of the American Fruit Grower. Among other things he says, "Just how 

 li>iuid lime-sulphur may reduce leaf activity to the extent that it does 

 has not been answered to any great satisfaction. Suggestions have been 

 made that the presence of the spray film on a leaf may cause the /breathing 

 pores' to close and obstruct the passage of the gaseous raw material used 

 in photosynthesis - carbon dioxide. Or there may be a destruction of the 

 internal Colls and the green coloring virithin the leaf tissues. It is defi- 

 nitely known that an abundance of green coloring, or chlorophyll, in the 

 leaves is highly essential for rapid and efficient food production. " 



Sulfur has be&n usod c-s a spray for over 100 yeL^rs. The earliest 

 record of its use is that of J. Robertson in iingland in 1821. In 1852 

 Grison prepared a material by boiling sulfur and slaked lime. This was 

 probably the forerunner of lime sulfur, the use of which was first sug- 



