SHADE TREES AND CATCH CROPS. 71 



Pigeon-pea. (See Cajanus mdicm.) 



Pina (Spanish). (See Ananas sativus.) 



Pina de Santo Domingo (Porto Rico). (See Casuarina equiseti folia). 



Pindar. (See Arachis Kyjpogaea.) 



Pineapple. (See Ananas sativus.) 



Piptadenia colubrina. 



Synonyms. — Acacia virginalis; Acacia angico. 

 Common name. — Angico (Brazil). 



A leguminous tree used in some parts of Brazil where coffee is cultivated in the 

 lowlands. Most of the Brazilian coffee is, however, grown without shade. The 

 synonyms are those given by Van Delden Laerne and by Raoul; Acacia virginalis 

 does not appear in the Index Kewensis, while Acacia angico is referred to Piptadenia 

 rigida. 



According to Van Delden Laerne, experiments in shading coffee with this tree were 

 made in the Sierra Abaixo of Brazil, in plantations situated at an elevation of less 

 than 300 meters. The plan was never carried out, whether from accident or unfavor- 

 able results is not known. With this exception the author mentioned states that 

 , m u trees yielding shade are unknown in Brazil." Open culture is commended on the 

 ground that the berries ripen in the dry winter season when low temperatures pre- 

 vail, thus decreasing the injury from drought. That the policy of open culture may 

 have been carried too far in Brazil is indicated, however, by the fact that even wind- 

 breaks are not used, although many trees are said to be injured by exposure. 



Piptadenia rigida. (See Piptadenia colubrina.) 



Pithecolobium dulce. 



Native names. — Huamuchil, or Guaymochil (Mexico) ; Manila Tamarind (India) . 



This species seems to be the favorite for coffee shade in the subarid regions of Mex- 

 ico, as far as preferences have been expressed in the undiscriminating literature of the 

 subject. The indications are, moreover, that the tree is worthy of general considera- 

 tion, at least for the drier of the coffee-growing regions, since in addition to vigorous 

 growth and ability to withstand drought it affords a valued edible fruit; the bark is 

 used for dyeing and tanning and the wood is of good quality. 



The origin of this tree is a matter of uncertainty, for though it is generally thought 

 to be a native of Mexico it is not known to occur wild in that country, and its name 

 seems not to be recognizable in the extensive lists of aboriginal plants known to 

 Hernandez. Moreover it seems not to be closely related to the American Pithecolo- 

 biums, and, like many other economic species, may have been introduced at an early 

 date from the Philippines. It was originally described from specimens introduced 

 from the Philippines into India, where it is extensively planted as a shade tree along 

 roads, for hedges, and in waste places for firewood or for charcoal. In the drier 

 regions of the western slope of Mexico the guaymochil is also extensively planted, 

 and is said to maintain itself well even in localities with but 2 inches of annual rain- 

 fall. The fruits are here the first consideration, and are an article of commercial 

 importance. According to Dr. Edward Palmer: 



The fruit of the tree is much sought after as food. It is very prolific, and the 

 white manna-like substance which adheres to the black seed is a favorite food with 

 all classes, especially those who have consumption, who eat it with the strong con- 

 viction of obtaining relief. In Colima it is so abundant that it is sold for 1 cent a 

 kilo. In Acapulco there is an ample supply of this fruit, and in spite of all the tropi- 

 cal fruits on the market it is a great favorite. It is surprising the quantity of fruit a 

 tree growing in a desert region with not more than 2 inches of rain a season will pro- 

 duce, and it grows from the Tropics to the region where there is ice. 



