Valley at some remote time. Today, J. candida is found 
neither in the eastern lowlands, nor in the western high- 
lands around Pasto, but several plants of D. candida 
‘Buyés’ (Bristol 1785) were seen in the upper Rio Juan- 
ambu drainage to the north. It may be postulated that 
D. candida was introduced to the Valley of Sibundoy 
via the trail from the Juanambu, and that following one 
or more such introductions the Valley became a centre 
of diversity. 
b em , 
Propagation 
All of the Datura cultivars in the Valley of Sibundoy 
are propagated exclusively by man through large cut- 
tings. During the annual clearing of the gardens in 
preparation for the planting of maize and beans, some 
of the many trees and shrubs in the gardens are pruned, 
pollarded or even cut back to the ground. The removal 
of branches from a Datura plant to permit more planting 
space is the usual occasion for propagation. A branch 
measuring half a meter or more is simply thrust into the 
loose sandy soil and given no further attention. Occa- 
sionally, a more methodical planting is undertaken when 
the branches are cut into fairly uniform pieces and 
planted out in a row as a kind of hedge along the edge 
of a garden. These plants will be weeded during the 
general garden weedings four times a year. 
Tree Datura branches at different stages of maturity 
differ in their capacity to root easily from cuttings. All 
of the leaves are borne on herbaceous stems which are 
only tardily lignified. Occasionally, usually after heavy 
pruning or pollarding, one or more stems grow up with 
unusual vigor and often reach a diameter twice that of a 
normal stem. The lignified part of normal stems is the 
least capable of forming roots under casual treatment; 
but the occasional, thick and uncommonly vigorous stems 
{ 182 | 
L 4 
