-3- 



appearance of magnesium deficiency on light soils which have not had sufficient 

 high magnesium limestone applied to correct magnesium deficiency. T»ees which have 

 teen heavily mulched should be adequately supplied with potassium. 



Ifegnesium requirements should be adequate where sufficient high magnesium lime 

 has been applied to maintain a soil pH of 6.0 to 6.5. It should be remembered that 

 it takes from 3 to U years before magnesium limestone can correct magnesium 

 deficiency. So where magnesium lime has not been applied for that length of time 

 spray applications of magnesium sulfate will have to be made as a temporary protec- 

 tion against magnesium deficiency. Three sprays of 20 pounds of magnesium sulfate 

 (Epsom salts) per 100 gallons commencing with the first cover spray, should prevent 

 magnesium deficiency. We believe that many orchards have not had sufficient lime tc 

 correct soil acidity, so we urge every fruit grower to have his soil tested to 

 determine whether or not his orchard needs more lime. 



To avoid the possibility cf boron deficiency, applications of borax should be 

 laade every 3 to 5 years. Suggested amounts of borax for trees of different age 

 groups are as follows: Trees up to 10 years of age, h ounces; trees 10 to 20 years, 

 8 ounces J trees over 20 years, 8 to l6 ounces. Do not apply over fifty pounds of 

 borax per acre. At high rates of application borax is an excellent v;eed killer. 



ViTe realize that these recommendations are of a general nature and vdll not 

 necessarily apply to every orchard. They are given as a guide. The fruit grower 

 vail have to make the final decision as to what fertilizer program he uses for each 

 block in his orchard, 



— W. D, TiTeeks 



USE OF INSECTICIDAL SPRAYS IN RODENT CONTROL 



In view of current interest by fruit growers in the possible use of certain 

 insecticidal sprays for the control of tree girdling mice, the following statement 

 from the Fish and Wildlife Service, Wildlife Research Laboratory, Denver, Colorado, 

 is circulated: 



"There has appeared within recent months considerable publicity on the use of 

 toxaphene in the control of meadow mice in orchards, hay and other field crops. The 

 use of toxaphene and other chlorinated hydrocarbon insecticides applied as a blanket 

 spray to the ground cover for the control of small rodents is a matter of current 

 research by the U. S. Fish and V/ildlife Service and State agencie_s . Procedures 

 still are in the research category and the method should not be used in operational 

 rodent control at this time , 



"The effectiveness of toxaphene in controlling meadovf mdce ( Microtus ) varies 

 with the density of the ground cover and the amounts of active toxaphene employed 

 per acre. Field results to date have been very erratic. Currently, large amounts 

 of active toxaphene per acre are being used experimentally. At this rate of appli- 

 cation a serious hazard e:;cists to game birds, domestic poultry and livestock that 

 may enter spiayed areas. 



"The Fish and Vifildlife Service recomir.ends that until research investigations 

 have been completed and appropriate recommendations formulated, no toxaphene or any 

 other toxic insecticide be emplo;yed as a ground spray in operational rodent control," 



— Carl B. Henry 



Assistant District Agent - Conn., 

 __ t.iasSj.,_R. I. 



