i8 



THE CUBA REVIEW. 



AGRICULTURAL. 



NOTES FROM ESTACION CENTRAL AGRONOMICA* 



Citrus Fruit Pests. 



Since the founding of the Estacion Ag- 

 ronomica in 1904 the troubles to which cit- 

 rus fruit trees are subject in Cuba have 

 been carefully investigated. 



Excepting the fruit fly, nearly every seri- 

 ous citrus fruit pest found in other coun- 

 tries is in Cuba, and there is at least one 

 important insect enemy here which has not 

 been recorded in other regions. To control 

 these troubles to such an extent that no one 

 of them needs to threaten the future of the 

 citrus fruit industry is possible to 'do, 

 but each orchardist should watch his trees 

 unceasingly and give them vigorous and 

 persistent treatment. 



The idea is absurd that citrus fruit can 

 be planted in Cuba and left practically to 

 take care of itself. Here, as everywhere 

 else, eternal vigilance spells success. 



The following list of some of the citrus 

 fruit troubles have been closely studied at 

 the Estacion : 



Bibijagua or Parasol Ant {Atta insularis, 

 Guerin). — They cut the leaves from orange 

 trees and other plants and will strip a 

 young orange tree in twenty-four hours. 

 This serious pest may be combatted by 

 smoking out the nest with sulphur fumes 

 forced into the nest by a bellows and in 

 compact, moist land by carbon disulphide 

 poured into the nests. This is more ex- 

 pensive than the sulphur treatment. 



Hormiga Brava or Fire Ant (Solenopsis 

 geminata, Fabr.) — A small brown ant which 

 in new land often 'does serious harm to 

 young citrus trees. They sting with much 

 vigor, causing a burning sensation for sev- 

 eral hours. When they make their nest 

 at the foot of an orange tree, they carry 

 up the soil and paste it to the side of the 

 trees, leaving galleries, made by biting 

 away the bark. A small tree may be girdled 

 in this way and killed. They are hard to 

 control, and promise to be one of the most 

 serious citrus pests. Constant breaking up 

 of the nests by complete clean culture and 

 spraying the disturbed ants with some strong 

 insecticide are recommended for protecting 

 the trees until their bark becomes thick and 

 strong. 



Root Grub and Blue-Green Beetle (Pach- 

 naeus litus). — This insect, in its larval 

 (grub) form injures the roots of citrus 

 trees and in its adult (beetle) form eats 

 holes in the leaves and injures the young 

 fruits, has not been reported as a citrus 

 pest in other countries, but is one of the- 

 worst enemies of the citrus orchards in 



* Our readers should study these notes carefully, 

 as the information is new and specially prepared 

 for the CUBA REVIEW. 



most parts of Cuba and should be watched 

 for carefully in all parts of the island. 

 In the larval form it is a footless white 

 grub which eats the bark from the younger 

 roots. As a result the tree begins to look 

 dry, the top turns yellow, and often the 

 tree dies. Yet the roots are often badly 

 eaten before the tree begins to show signs 

 of injury. 



As a grub it is very difficult to combat. 

 Lifting the trees and picking the grubs 

 from the roots and out of the soil is slow, 

 expensive and dangerous to the tree, and 

 as yet no safe soil treatment for destroy- 

 ing the grubs can be definitely recom- 

 mended. The beetles, however, are easily 

 killed. 



They appear with the spring rains and 

 live through the summer and fall, injuring 

 the trees and laying their eggs. By De- 

 cember practically all have- disappeared. 

 The best method for catching them is by 

 the use of a frame covered with cloth. 

 This is placed under a tree on a cool day 

 or in the early morning, the tree is shaken 

 and the beetles fall into the cloth, from 

 which they may be picked and destroyed. 

 Spraying the trees with an arsenical poison 

 is also recommended. 



Scale Insects. — The experiment station 

 reports having found fourteen different 

 species of scale insect on the citrus trees 

 in Cuba. They are as follows : Purple or 

 oyster-shell scale, chaff scale, long or Glov- 

 er's scale, California black scale, round 

 black or Florida red scale, hemisphere or 

 brown scale, Chionaspis scale or small 

 white bark louse, Cuban or large turtle-back 

 (a ne wscale), Hesperides scale or Florida 

 turtle back, wax scale, a red scale which is 

 probably the California red scale, mealy 

 bug, Florida white fly, cottony white fly 

 (improperly called guava white fly). 



Most of these scales have natural ene- 

 mies (other insects and certain fungous 

 diseases) which keep them more or less in 

 check. But if not present it is necessary 

 to spray the trees and the station is pre- . 

 pared to give detailed advice as to spray 

 mixtures and apparatus. 



Rust Mite. — This minute insect is very 

 prevalent in Cuba; it causes the russet or 

 silvery color so often seen in citrus fruits, 

 which never command quite as high a 

 price as the bright, natural-colored fruit. 

 Spray made as follows will practically ex- 

 terminate the mites and also the red spiders, 

 which are a dry-weather pest affecting the 

 leaves : 



Flowers of sulphur 7 'bs. 



Flour (in a cooked paste) 2 lbs. 



Water •. 5° gals. 



One application, at the beginning of a 

 long dry spell "will sometimes free an 



