Dry Deciduous Forests of the Poona District, Deccan, India

The deciduous vegetation grows in various ghats and hills in the Poona district. The present note describes the type from the Katraj ghats, on the south of Poona at a distance of 6 miles.

The area consists of flat plateau at the top, eastern and western slopes and narrow valleys through which small rivulets flow during monsoons. The mountains are formed of trap rock, the strata of which dip towards east. Thus the eastern slopes are gentle with better developed soil but the western escarpments are steep comparatively dry with shallow soil. Seepage water is seen on eastern slope during monsoon. Alluvial soil deposits in the valley. The average rainfall is about 27".

The following vegetation types are described:

(I) Top of the plateau: They are mainly covered with Boswellia serrata which is regenerating profusely where biotic interference is excluded and the soil is dry shallow and gravelly.

(II) The western slopes: These slopes bear a low type of forest. The following trees are common-Boswellia serrata, Lannea coromandelica, Diospyros montana and Largerstroemia parviflora. Shrubs-Acacia sp., Lantana camara, Zizyphus xylopyrus, Rhus mysorensis, Flacourtia, Cipadessa baccifera, Gymnosporia spinosa and Securinega sp.

Herbs-Tridax procumbens, Leucas sp., Cocculus sp., Polyzygus tuberosus, Sida sp., Arisaema sp., Desmodium sp., Acanthospermum hispidum, Celosia sp. etc.

This vegetation is also affected adversely by the biotic interference since lopping, coppicing and grazing are prevalent.

(III) Eastern slope (top portion) ; It bears a community of Boswellia serrata-Diospyros montana-Lannea coromandelica on dry shallow and rocky soil. The commonest shrubs are Acacia sp., Zizyphus xylopyrus, Lantana camara, Cryptolepis buchanani, Woodfordia fruticosa, Cissuspallida and Securinega sp.

The common herbaceous vegetation consists ot Locculus sp., Leucas sp., Tridax procumbens, Curculigo sp., Polyzygus tuberosus, etc.

(IV) Eastern slope (lower portion): It bears a community of Tectona grandis-Lannea coromandelica-Diospyros-Boswellia serrata.

Teak and Lannea coromandelica are predominant on the alluvial deposits towards the valley and higher up. Diospyros sp. and Boswellia become prominent in dry trap soil. Diospyros on alluvial soils is heavily infected by Viscum. But incidence of the parasite decreases in trees which are growing on dry trap rocks elsewhere in the area. Commonest shrubs in the community are Acacia sp., Clerodendron serratum, Zizyphus xylopyrus, Cissus pallida and Lantana camara. Commonest herbs are Leucas sp., Tridax procumbens, Hemidesmus indicus, Curcuma montana, Cocculus sp., Polyzygus tuberosus, Trichodesma sp., Crotalaria sp., Indigofera sp., Celosia sp., Aerva javanica, etc.

Various stages of succession are seen in the area and regeneration of teak, Boswellta, Lagerstroemia. Lannea is common on different types of soils.