Study Area

Kolar district is located in the southern plain region of the Karnataka State (Figure 1). It lies between 77°21’ to 77°35’ east longitude and 12°46’ to 13°58’ north latitude and extends over an area of 8225 sq. km and divided into 11 taluks (for administrative purposes).  The average population density of the district is 2.09 persons/ha (rural) and 2.69 persons/ha (rural and urban). The population density ranges from 1.44 (Bagepalli), 1.69 (Gudibanda), 1.70 (Srinivasapur) to the maximum of 2.55 (Kolar). While, the population density in taluks are – Bangarpet (2.52), Malur (2.38), Gauribidanur (2.36), Sidlaghatta (2.16), Chintamani (2.10), Mulbagal (2.04), Chikballapur (1.92). The tree species predominant in the district are Acacia nilotica (Indian gum Arabic), Acacia auriculiformis (Earpod wattle), Albizia amara (Chigarae), Albizia lebbek (East Indian Walnut Tree), Azardirachta indica (Neem Tree), Eucalyptus sp. (Eucalyptus), Mangifera indica (Mango tree), Pongamia pinnata (Indian Beach Nut Tree), Prosopis juliflora, Tamarindus indicus (Tamarind Tree) etc. Among these, the fuel wood trees preferred by local people are Prosopis juliflora. Acacia nilotica, Acacia auriculiformis. and Eucalyptus sp. Due to scarcity of fuel wood in some parts of the district, a section of the population is meets its cooking and heating energy requirement from shrubs and weeds like Lantana camara (Lantana) and Cassia auriculata (Tanner’s Cassia).

Prosopis juliflora - Fuel wood Tree: These are spiny shrubs and trees, very variable, small to medium sized, aggressively fast growing tree, semi-evergreen to evergreen, large crowned, with drooping low branches, with bipinnate leaves, greenish-yellow flowers cylindrical or flat and flowering almost throughout the year. The species include several varieties and forms; two important and well-known varieties besides var.chilensis are: var. velutina and var.glandulosa. Six species are reported in India; Prosopis cineraria (Mesquite) are indigenous and others have been introduced Prosopis chilensis(Mesquite), an American species, and var.glandulosa has run wild in many parts. When the growth of Prosopis juliflora is disturbed through hacking or cutting its auxiliary bud becomes more active than the terminal bud and starts producing innumerable number of branches. So the tree attains a more bushy form or becomes shrub like instead of a tree. But if left undisturbed it can grow to a tree form even with a girth at breast height of more than 100 to 200 cm [35]. Prosopis juliflora grow well in basic soils like the black cotton soil and hence, it is widely distributed in black soils of Andhra Pradesh and northern Karnataka. It prefers plain land soils instead of hilly soils as the latter have less surface soil volume. It prefers soils well drained with water but can’t survive in deep standing waters. In many villages of Kolar district,  Prosopis juliflora is used as fuel wood due to its easy accessibility, availability, calorific value, growth rate, short cycling period, coppicing capability, etc. Gauribidanur taluk, which lies in northwestern side of the district where the growth of fuel wood species Prosopis juliflora is profuse, was considered for validation of mapping.

Fig. 1. Study area.