constant humidity. It is readily propagated by root cuttings; it 
should be planted in rows 35 centimeters apart, with approxi- 
mately 25 centimeters between the plants in the rows. After 
two years, under favorable conditions, an average of 25 tons of 
green ixbut forage may be harvested per hectare per year; with 
two cuttings in the rainy season and one in the dry season. Each 
time the forage is cut, new growth is stimulated. If cared for 
properly, an ixbut pasture should last 15 to 20 years. 
Ina laboratory analysis, Aguilar (15) found that ixbut leaves 
(Euphorbia lancifolia) contained 7.46 per cent protein, as com- 
pared to 4.72 per cent for alfalfa (Medicago sativa). 
In 1949, Dr. Manuel Serrano (11), in collaboration with 
Merck & Co., Inc., investigated the effect of ixbut on the milk 
production of 6 goats in Guatemala City. The goats were given 
a 5% aqueous infusion of fresh ixbut plant material daily, fora 
period of 4 days. No signs of toxicity were noted. A modest 
increase in goat’s milk production was observed in each case. 
During 1949, tests were made of the insecticidal properties of 
78 species of plants from tropical America used as fish poisons, 
insecticides or drugs (16). Through several years, roots, stems, 
leaves, flowers and seeds were collected and tested at the 
Puerto Rico Agricultural Experiment Station, Mayaguez, 
Puerto Rico, to determine the toxicity of the materials to in- 
sects. 
Five species were found to be highly toxic; 30 species par- 
tially toxic; while 43 species, including ixbut (Euphorbia lan- 
cifolia) were found to be non-toxic to insects. 
In 1957 (17), Squibb, Braham and Scrimshaw carried out 
experiments on the utilization of the carotenoids of ixbut 
(Euphorbia lancifolia), teosinte (Euchlaena mexicana), yellow 
bamboo leaves (Bambusa vulgaris) and green bamboo leaves 
(Bambusa ventricosa), by New Hampshire chicks over a 
5-week feeding period. The carotene content and vitamin A 
activity of dehydrated forage meals prepared from these in- 
gredients were studied. It was found that ixbut contained the 
highest carotene content of the four forages and maintained the 
highest serum levels of vitamin A. The dehydrated meals pre- 
vented mortality and permitted good weight gains. 
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