No. 7. DErARTMENT OF AGRICULTURE. 99 



precipitate, it was not inetfective as an arsenical poison, making thus 

 a combined insecticide and fungicide. Therefore, the formula that 

 is now recommended as a summer spray for these dual purposes, is as 

 follows: 



On potatoes and other hardy plants, one gallon of strong con- 

 centrated lime-sulfur solution, aud one and one-half or two pounds 

 of arsenate of lead to twenty-five gallons of water. On apple, pear, 

 (juiuce and other fairly hardy plants, one gallon and one quart of 

 the strong lime-sulfur solution, and two pounds of arsenate of lead 

 in fifty gallons of Avater. On very delicate plants, like the peach, 

 one gallon of strong lime-sulfur solution, and four pounds of arsenate 

 of lead in two hundred gallons of water. 



It is fortunate that the time has come when the horticulturist 

 aud agriculturist can, with only three materials, keep in control 

 the pests that are liable to assail and destroy his growing property. 

 These materials are the two mentioned above for the chewing in- 

 sects and plant diseases, and also for the scale insects during their 

 dormant season, and whale oil soap, or tobacco, or kerosene, for the 

 sucking insects, — such as plant lice and young scale insects during 

 the summer time. 



We have proven that Peach-tree borers, which are really the worst 

 insect enemies of the jjeach, since the San Jose scale is so easily 

 controlled, can be prevented and controlled by spraying or washing 

 the base of the peach trees about the middle of the month of June, 

 with a strong lime-sulfur solution to which has been added arsenate 

 of lead, and then mounding the trees. 



The regular winter formula of lime-sulfur, especialy with sediment 

 present, and containing one or two pounds of arsenate of lead to 

 fifty gallons, applied to the base of peach trees has, in ninety-nine 

 per cent, of the cases tried by us, resulted in preventing any attack 

 by the Peach-tree borer. We recommend that this be applied from 

 the middle to the last of June, and that the trees be at once mounded 

 to a height of about six inches or a foot, being sure that the liquid 

 has covered the bark both above and below^ the top of the mound 

 of earth. 



White Lead and Eaw Linseed Oil on Fruit Trees: A great deal has 

 been published recently concerning the effects of Avhite lead and 

 linseed oil on fruit trees. We used it two, three and four vears asro 

 on peach, apple and pear trees, being careful to apply pure white lead 

 and f)ure raw linseed oil. One application was made, but it was 

 thorough, being appied witli a brush to the trunk of the tree down 

 to tho ground. The trees showed absolutely no etTects of injury, 

 excepting a slight cracking of the very outermost bark layer to which 

 the paint was directly a])plied. It is |)robable that this was no more 

 than the natural splitting or cracking of the bark in the process of 

 growth. The borers of the pome fruits were effectually prevented, 

 as well as no damage by mice and rabbits. While we would not 

 recommend the regular annual application of oil, we think it would 

 be safe to use it at least once every two years. 



Owing to the lack of facilities in the way of a place for experi- 

 mental work, the ex])erimentation of this office has not been exten 

 sively conducted during the past 3'ear. 



