cover large areas of native grasslands, including the Mukurthi Hills, and was declared a pest "useful for covering wastelands.". Some black wattle plantations were maintained for the leather industry, as their bark yielded tannin. In 1882 Inspector General of Forests, Dietrich Brandis "recommended bringing the present of plantation up to to create enormous forest blocks "...which would make any remaining sholas redundant forest resources." The entire area of MNP, was declared as a Reserve forest in 1886. In 1920 it was suggested that 10–15 acre plots in the Kundah Hills including the present park area, "be planted up each year in places where sholas have almost or quite disappeared, the most suitable species probably being Acacia dealbata (silver wattle)", thus replacing highly diverse endemic and stable ecosystems with an exotic monoculture supporting little animal diversity. The area was declared as a wildlife sanctuary on 3 August 1982 and upgraded to a National Park on 15 October 1990 in order to protect the Nilgiri tahr. Geography Mukurthi National Park has an elongated crescent shape facing to the west between 11°10' to 11°22' N and 76°26' to 76°34' E. It is bordered on the west by Nilambur South Forest Division, to the northwest by Gudalur Forest Division, to the northeast, east and southeast by Nilgiri South Forest Division and to the south by Mannarghat Forest Division. At its southwest tip the peaks of this park straddle the northeast corner of Silent Valley National Park of Kerala. On the Nilgiri Plateau, the Kundah range of the Nilgiri hills is a ridge on the south-western side of Mukurthi National Park bordering Kerala. The Tamil Nadu/Kerala border here is 39 km long. The park generally slopes towards the east and south receiving water from the Billithadahalla, Pykara and Kundah rivers, and the Upper Bhavani and Mukurthi reservoirs which flow through the park. Also several perennial streams originate in the park, most of which drain into the Bhavani River. Park elevation varies from to , with Kollaribetta , Mukurthi , and Nilgiri being the highest peaks in this part of Nilgiri District, Tamil Nadu. With elevations greater than the general level of the plateau, the range possesses some peaks close to the height of Doddabetta, just east of Ooty. Avalanche hill of this range has twin-peaks of the Kudikkadu (height: ) and the Kolaribetta. Derbetta (or Bear Hill) (height: ) and Kolibetta (height: ), south of