The clover mite[197] (_Bryobia pratensis_ Garman) formerly considered a serious pest of the plum only in the far West, is now abundant in plum orchards in New York. It can be controlled by applications of lime and sulphur. The bumble-flower beetle[198] (_Euphoria inda_ Linnaeus) is reported by Goff to be occasionally very injurious to plums in Wisconsin. Remedies seem not to have been tried. The larvæ of the cherry slug[199] (_Selandria cerasi_ Peck) is not infrequently found doing damage to plum foliage and occasionally the larvæ of one or two other saw-flies feed on the plum. These are all overcome by the use of arsenical sprays. At least one of the curious insects know as “case-bearers” attacks the plums. The troublesome one is the pistol case-bearer[200] (_Coleophora malivorella_ Riley), which is not often a pest but has sometimes done considerable damage. Attempts to check this insect with the arsenical sprays have usually proved successful. The plum tree is a host-plant of the hop aphis[201] (_Phorodon humuli_ Schrank). So much does this insect feed on the plum that the destruction of plum trees in the vicinity of hop fields is recommended to hop-growers by Riley. CHAPTER III LEADING VARIETIES OF PLUMS. ABUNDANCE [Illustration: ABUNDANCE] _Prunus triflora_ =1.= _Am. Pom. Soc. Rpt._ 96. 1887. =2.= _Am. Gard._ =9=:360. 1888. =3.= _Ga. Hort. Soc. Rpt._ 51, 52, 53, 99. 1889. =4.= Bailey _Ann. Hort._ 103. 1889. =5.= _Am. Pom. Soc. Rpt._ 106, 125. 1891. =6.= _Am. Gard._ =13=:700. 1892. =7.= _Rural N. Y._ =52=:666. 1893. =8.= _Cornell Sta. Bul._ =62=:19, 27, 32. 1894. =9.= _Tex. Sta. Bul._ =32=:488. 1894. =10.= _Rev. Hort._ 160. 1895. =11.= _Mich. Sta. Bul._ =118=:52. 1895. =12.= _Cornell Sta. Bul._ =106=:41, 43, 44, 47, 48, 49. 1896. =13.= _Va. Sta. Bul._ =67=:96. 1896. =14.= _Cornell Sta. Bul._ =131=:195. 1897. =15.= _Ibid._ =139=:37, 38, 39, 40. 1897. =16.= _Am. Pom. Soc. Cat._ 26. 1897. =17.= _Cornell Sta. Bul._ =175=:141, 142, 143. 1899. =18.= Waugh _Plum Cult._ 132, 135. 1901. =19.= _Mich. Sta. Bul._ =169=:242, 248. 1899. =20.= _Ont. Fruit Exp. Sta. Rpt._ 15. 1902. =21.= _Ohio Sta. Bul._ =162=:254, 255. 1905. =22.= _Texas Nur. Co. Cat._ 9. 1907. =23.= _Ga. Sta. Bul._ =68=:7, 28. 1905. _Abundance_ 7. _Babcock_ (?) 15, 17. Babcock 12, 16, 18. Botan 1, 2, 3, 5, 6, 10. _Botan_ 12, 16, 18. _Botankio_ 12. Botankio 3. Burbank No. 2, 11, 12. Chase 12. _Chase_ 14, 15, 17. Douglas 9, 15, 18. _Douglas_ 17. _Hattankio_ 8, 15. _Hattonkin_ 12. _Hytankayo_ 8, 9. Munson 8. _Munson_ 9, 18. Oriole 22. Sweet Botan 7. _Sweet Botan_ 15. _Yellow Fleshed Botan_ 3, 6, 8, 17, 23. Yellow Fleshed Botan 5. _Yellow Japan_ 12. Yellow Japan 8, 14.