45(') KKPOKT OK OKKICK <»K KXI'KKIMENT STATIONS. 



socurod, soiiio of tlu'sc may hccoinc proiitaMf aI•ti('l(^s of expert. 

 There are, however, many dilliculties, aside from those of transporta- 

 tion, in makino* a prolitahh' market for new and untried fruits, and 

 attempts in this direetion should be made cautiously and, at first, on 

 only an experimental scale. A few thrifty grapevines were observed 

 in the neigliborhood of Ponce. Judging from observations made in 

 Jamaica, it is prol)al)le that some of tlie European or Califoi-nia varie- 

 ti(\s ( Vlflsin.nlfer<i) will thrive well on the southern or dry side of the 

 island, and that they will ripen their crops well in advance of Cali- 

 fornia, proba])ly dui'iiig May and June. If this })r()ves to ])e a fact 

 tlnMr cultivation would be prolitable, provided adecpiate transportation 

 facilities ct)uld be secured, since the American market is bare of grapes 

 at this season. 



NOTES ON DISEASES AND INSECTS. 

 ORANCxES. 



Orange scab {Cladosjyorium. sp.).^' — This is the only fungus disease of 

 the orange that was o])served. It causes wart-like swellings and dis- 

 tortions on the leaves and fruit. It does not often attack sweet 

 orang(>s, but is usually confined to the sour oranoes and the lemon. At 

 present in Porto Rico it is doing no serious damage except to sour- 

 orange seedlings in the nursery. A little more care in locating seed 

 beds and mirseries at some distance from infected sour trees will pre- 

 vent injuiT from this disease. It is imwise to plant nursery stock 

 between the rows of orchard trees on account of the danger of the 

 spreading of diseases and scale insects. Spraying with Bordeaux mix- 

 ture or the ammoniacal solution of coj)per car])onate will protect trees 

 from injury by scab. Spraying oranges with fungicides should only 

 be resorted to as a last resort, as such sprays will kill the fungus 

 enemies of the scale insects that are mentioned below. 



Scale insects. — Four dift'erent scale insects were observed on the 

 orange, any one of which would do great damage if allowed to multi- 

 pi}' unchecked. Fortunately, a hymenopterous pai'asite and several 

 fungus parasites are doing much toward destroying them. Judging 

 from the thrifty condition of most of the old seedling trees, it seems 

 reasonable to hope that these natural enemies will in the long run be 

 able to prevent serious damage. The fact remains, however, that many 

 individual trees are now suffering seriously from scale, and planters 

 should provide themselv^es with the necessar}^ apparatus for spraying 

 these infested trees. It is doubtful if general spraying is either 

 necessaiy or advisable, since it would tend to destro}^ the friendly 



« Swingle and Webber, IT. R. Dept. Agr., Division of Vegetable Physiology and 

 Pathology Bui. 8, 1896, j)]). 20-24. 



