ILLUSTRATIONS 
PLATE 1 
Fic. 1. Tachin River near Ban Mai, showing nipa, Nipa fruticans Wurmb, 
swamp and thatched hut of an orchardist. 
2. Canal leading from Tachin River to the inland orchards. The river 
is at low tide. ; 
3. Irrigation and drainage canal in the Nakorn Chaisri orchard section. 
PLATE 2 
Fig. 1. Grass and nipa swamp at Ban Mai, Nakorn Chaisri. The land 
in the foreground has been cleared and is ready for the prepa- 
ration of mud dikes and canals. 
2. A raised dike along a canal in the Ban Mai region. The land is 
being prepared for pummelo culture. The embankment is a 
meter or less higher than the surface of the interior beds. 
3. Jak trees, Artocarpus integra (Raderm.) Merr. (A. integrifolia 
Linn.), planted along the edge of a dike. Pummelo trees are 
planted within, on the first bed. 
PLATE 3 
Fic. 1. Digging ditches in the preparation of the beds for the citrus orchard. 
The soil is used in the construction of the raised beds between 
the ditches. 
2. Preparation of ditches in the process of forming raised beds for 
pummelo culture. The soil is removed by hand after being cut 
into blocks with a special spade. 
3. Prepared beds in a newly developed plot planted to sugar cane 
before being ready for the citrus. 
PLATE 4 
Fig. 1. Newly prepared beds planted to bananas before being ready for 
the citrus, 
2. Automatic water gate, leading from the canal through the dike 
into the ditches in the orchard. The pipe is made of a palm-tree 
trunk. The water is ati low tide. 
3. An older cultivated area in the Nakorn Chaisri region, showing 
the irrigation and drainage canal and the orchard land on both 
sides. 
PLATE 5 
Fic. 1. One of the best-managed Nakorn Chaisri pummelo groves at Ban 
Mai. 
2. Cement steps leading from a main canal up to the orchard house. 
3. Bruguiera sexangula (Lour.) Pers. and pineapples planted on a 
dike along a canal. The roots of the trees help to keep the earth 
at the base of the dikes in place. 
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