450 km. In the eastern part of the state lies the coastal plain. It extends from the Subarnarekha River in the north to the Rushikulya River in the south. The lake Chilika is part of the coastal plains. The plains are rich in fertile silt deposited by the six major rivers flowing into the Bay of Bengal: Subarnarekha, Budhabalanga, Baitarani, Brahmani, Mahanadi and Rushikulya. The Central Rice Research Institute (CRRI), a Food and Agriculture Organization-recognised rice gene bank and research institute, is situated on the banks of Mahanadi in Cuttack. The stretch between Puri and Bhadrak in Odisha juts out a little into the sea, making it vulnerable to any cyclonic activity. Three-quarters of the state is covered in mountain ranges. Deep and broad valleys have been made in them by rivers. These valleys have fertile soil and are densely populated. Odisha also has plateaus and rolling uplands, which have lower elevation than the plateaus. The highest point in the state is Deomali at 1,672 metres in Koraput district. Some other high peaks are: Sinkaram (1,620 m), Golikoda (1,617 m), and Yendrika (1,582 metres). Climate The state experiences four meteorological seasons: winter (January to February), pre-monsoon season (March to May), south-west monsoon season (June to September) and north east monsoon season (October–December). However, locally the year is divided into six traditional seasons (or rutus): Grishma (summer), Barsha (rainy season), Sharata (autumn), Hemanta (dewy),Sheeta(winter season) and Basanta (spring). Biodiversity According to a Forest Survey of India report released in 2012, Odisha has 48,903 km2 of forests which cover 31.41% of the state's total area. The forests are classified into: dense forest (7,060 km2), medium dense forest (21,366 km2), open forest (forest without closed canopy; 20,477 km2) and scrub forest (4,734 km2). The state also has bamboo forests (10,518 km2) and mangroves (221 km2). The state is losing its forests to timber smuggling, mining, industrialisation and grazing. There have been attempts at conservation and reforestation. Due to the climate and good rainfall, Odisha's evergreen and moist forests are suitable habitats for wild orchids. Around 130 species have been reported from the state. 97 of them are found in Mayurbhanj district alone. The Orchid House of Nandakanan Biological Park hosts some of these species. Simlipal National Park is a protected wildlife area and tiger reserve spread over 2,750 km2 of the northern part of Mayurbhanj district. It has 1078 species of plants, including