production. Fertilizer recommendation for
immature state of the old plantation area is
20-8-20 and 20-10-12 tor a new region.
Application rate depends on rubber age and
soil texture. Nitrogen. fertilizer in this phase
can be reduced by legume intercropping. ln
tapping phase, 30-5-18 fertilizer is
recommended (6). However, the farmer still
apply various kinds of fertilizers which are
available in their villages (28). Moreover they
do not apply fertilizer every year. So the
rubber tree can not produce a high latex