The genus Cinnamomum

162 Nguyen Kim Dao
soil 5–10 cm high and 0.6–0.8 cm wide, adjusting the shade at 50%, and replacing
dried up seedlings.
Second to fourth years: Tend twice every year, first in January, February, March as done in
the first year. The shade intensity required for a two-year old forest is 40%, that of
three-year old forest is 30% and that of four-year-old forest is 20%. The second time in
August, September and October. Trimming the lower and diseased branches, piling up
soil at the foot of the plant and replacing dead trees are the important activities.
Fifth to tenth years: Tend once every year in May, June and July. Clear all the vegetation
cover, shading for a five-year old forest is 20%. From the sixth year shade is completely
removed, followed by the clearing and cutting of diseased and stunted branches. In a tenyear
old plantation, thinning is done for adjusting the density of trees to 1000–1250/ha.
Harvesting period: Ten years later (20 years after planting) in Vietnam. In China, cassia
harvesting is done as in the case of cinnamon (extracting bark from copieced shoots) and
the first harvesting starts about four to five years after planting and subsequent harvests
are conducted in three- to four-year cycles. However, in Vietnam, the harvesting is done
15–20 years after planting.
Protection and management
Protect the plantation from forest fire, cattle trampling and monitor for disease occurrence.
Prune to regulate tree structure: the first pruning should be done in May–June
of the tenth year, and the density is maintained at 1000–1250 trees/ha. The tree interval
should be 4 m and the row interval should be 2 m following the quincunx. The aims
of pruning are proper development of trees that are free from disease, and which have
symmetrical leaf canopies and trunks over 8 cm in diameter. All branches must be
pruned at a distance of 2 m from the base to produce straight trunks and better bark.
The second pruning is in February/March or July/August in the fifteenth year when
the density is reduced to 625 trees/ha; that means the tree as well as the row interval is
4 m. Clean the forest periodically.
Harvesting
Twenty-year old cinnamon trees are harvested in Vietnam. There are two crops: the first
crop is harvested from February to March (in the south) and from April to May (in the
north); the second crop is harvested from July to September (in the south), from
September to October (in the north). The bark extracted from the first crop has more
scales than that of the second one, and the second crop bark is of better quality. In many
growing areas in China, harvesting starts four to five years after planting and is continued
with every three to four year cycle.
The harvesting technique
In Vietnam
The harvesting of cassia bark depends on the accumulated experience of growers in each
area. In the north of Vietnam scaffoldings of 4–5 m high are erected around the trees to