The predominant forest type in Knyszyńska Primeval Forest is mixed coniferous wood in which pine and spruce are most frequent. Some parts of ancient forest are well preserved, too. You can see there pines as old as 200 years.
The reserve is the smallest one in Czarna Białostocka commune, and second oldest - after "Budzisk" It was created in 1972 on the area of 16,57 hectares. The reserve landscape is dominated by old, sloping pines and a little bit smaller spruces. Birch or oak are very rare. The pines can reach 30 metres high, and the diameter of their trunk comes to nearly 80 centimeters. In shrubs’ layer hazel is predominant, and in the undergrowth layer - species typical for coniferous forest, such as feather reed grass (Calamagrostis arundinacea), common wood sorrel (Oxalis acetosella), billberry, lily of the valley (Convallaria majalis). Eight plant species in the reserve are under strict protection. To the most interesting species belong: -lesser rattlesnake plantain (Goodyera repens), -mountain arnica, -Turk's cap lily.