62 SOCIAL SCIENTIST The hill tribes of this region practice two main types of cultivation. The predominant methbd of agricultural production is that which involves the shifting of cultivation, and is locally known sisjhum. The other is terrace cultivation. Despite being the dominant method of agricultural production in the hills, jhum cultivation has the least capacity^ compared to other forms of primitive agriculture,, measured in terms of the population per square kilometre it can support.2 B K Roy Burman's estimates of the capacity of different types of cultivation are given in Table I below. TABLE I Type of Agriculture Productive Capacity [Population per hectare it can support) \ Primitive Agriculture in settled villages 0.6 to 2.00 2 Primitive herdsmen 0.25 to 0.60 3 Shifting Cultivation (Jhum) 006 to 0.25 Under the system of j'hum or shifting cultivation a different piece of land is cultivated every year and is subsequently left fallow fora number of years before it is brought under cultivation again.3 Thus the nature of agricultural activity under such a system is fundamentally different from that under normal systems of agricultural production. The predominance of shifting cultivation in the hill region under study is due mainly to the following factors: a) The hill slopes cannot hold water and manuring is not possible as it gets drained out with the rain water. So/for the regenera" tion of the soil a plot has to be left fallow for a number of years after it is cultivated; b) The sparse population and the excess of land (fertile or otherwise) encourages such a system of cultivation. * The natural conditions of production in the hill regions, and consequently, the level of the productive forces prevailing in this area, significantly affects the nature of the organisation of production itself. Impact on Property Relations There are two main types of property right in land which are in existence in this area associated with the two different forms of cultivation. Taking exceptions into consideration, it is noteworthy that areas with shifting or jhum cultivation have not seen the natural growth of private property in land, whereas in the areas where terrace cultivation is predominant there is a tendency for the growth of private property in land. But one should be cautious and not draw hasty conclusions from the above statement. To quote Marx sf it would be wrong to regard them (that is primitive communities—AKB) as all being on the same level: as in the case of geological formations, historical formations constitute a whole series of primary, secondary and tertiary types.55A