LONCHOCARPUS, DERRIS, AND PYRETHRUM CULTIVATION D 
ture reported in 1924 on insecticidal tests made with lonchocarpus 
roots. Neither derris nor lonchocarpus was imported by the United 
States for peer processing until 1931. By 1937 total imports 
slightly exceeded 2,000,000 pounds. The 11,369,000 pounds im- 
ported in 1946 represented the largest quantity ever purchased by 
the United States in one year, but even that amount was not sufficient 
to satisfy a potential annual demand which has been estimated at 
about 25,000,000 pounds. 
Rotenone insecticides are usually marketed as dusts or as spray 
and dip concentrates. The dusts generally consist of finely ground 
root well mixed with some inert filler, such as tale or pyrophyllite. 
They may also be inert powders impregnated with root extracts. 
Most common sprays are either emulsions of water and root powder 
or root extracts diluted in appropriate solvents. Livestock-dip baths 
may be prepared by making water emulsions of ground root or liquid 
extracts. Infusions of macerated fresh roots serve as effective sprays 
and dips. 
LONCHOCARPUS 
BOTANY 
In recent years one of the lonchocarpus species has become the 
primary source of world rotenone supplies because of a steadily grow- 
ing plantation industry which has developed in the Amazon headwater 
region of eastern Peru. As yet, botanists are not in agreement as 
to the name of this Peruvian plant which has become so important 
economically. This hesitancy may be attributed in part to a lack 
of flowering and fruiting herbarium collections, which are necessary 
for a satisfactory taxonomic decision. Krukoff and Smith (16) 
called this plant ZL. utilis after having studied their collections of leaf 
specimens. Hermann (9) prefers to classify the same plant as L. 
nicou, variety utilis. 
Rare flowering and even less frequent fruiting are apparently 
characteristics of the commercially important lonchocarpus species. 
Research workers at Tingo Maria, Peru, in 1944 induced flowering 
of the commercial species ‘cultivated in that area by girdling bri anches 
of 2%-year-old plants (3); so it is possible that taxonomists may 
eventually have fertile specimens to study. The type specimen of 
L. nicou was collected in French Guiana and described by Aublet in 
1775. Today only leaf fragments remain of that material, and there 
are apparently no known fertile collections of authentic French 
Guiana L. nicow available to taxonomists. 
The only well-documented species of commercial lonchocarpus is 
L. urucu, which was named by Killip and Smith (/4) in 1930 after 
their explorations in the Brazilian Amazon Basin, where they gath- 
ered specimens with flowers and legumes (fig. 2 and fig. 3). LZ. wrueu 
is the source of most of the roots exported from Brazil. Perhaps until 
adequate fertile collections are obtained of French Guiana L. nicou 
and of the Peruvian species, which Krukoff and Smith call L. utilis, 
the taxonomy of the most important insecticide plant produced in the 
Western Hemisphere will remain confused. 
