de Bie, Kees 
increased to 144 even though 8 of the old orchards were uprooted. The orchards 
are found on three terrain units, i.e. in 1984: hills (29x), footslopes (48x), and 
terraces (67x; Figure 1). A general climatic overview is shown in Figure 2. The 
undulating fluvial terraces (400-500 masl) are composed of gravel and sand with 
some clayey inclusions that date back to the Upper-Tertiary to Lower-Pleistocene; 
the hills (500-1800 masl) consist of Carboniferous sediments such as quartzite, 
sandstone, siltstone, shale and chert that originate from meta-sedimentary rocks* 
(RLE 1993, Intrasuta 1983). 
  
  
  
  
dinates (m); 
Zone 47 
(Everest Sph.) 
  
  
    
m 
c h 
5000 7500 520000 2500 5000 
  
Orchards in 1977 pum i 
Orchards in 1984 j Footslopes #7 Roads 
Orchards surveyed in 1993 
  
Rivers 
Hills (mostly national park) " ; 
canals 
  
Paddies in Floodplain 
d Built-up area Water 
] S* bodies 
Figure 1. Map of North Phrao showing the location of orchards by 
terrain unit in 1977 and 1984 plus those sampled in 1993. 
(Terrain map based on RLE 1993 at 1: 50.000). 
  
  
4 Intrasuta (1983) states that metamorphic rocks in hills consist of orthogneiss, paragneiss and high- 
grade schist (Cambrian to Ordovician) plus low-grade phyllite, quartzite and slate (Devonian). 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000. 323