The city's greenery is protected according to the law on environment protection and the law on forests. The areas of greatest value are subject to additional legal protection.
In the course of the last few years there have been established 3 ecological sites: Olszak I, Wilczy Młyn and Główna which are protected due to their valuable natural features.
The city limits also include 2 nature reserves: the Żurawiniec Reserve established to protect the peat bog flora, and the natural and astronomical Morasko Meteorite Reserve established to protect the fall areas of the meteorite which left 7 craters forming the Europe's largest concentration of craters in one place. The Reserve is also interesting due to the retained flora and animals.
Within 15 km south of Poznań there is the Wielkopolska National Park (established in 1957), where 18 areas of strict protection were formed on the total surface of 260 ha. There are various protected forms of post-glacial landscape and the most natural flora assemblage and the associated animals. 5 marked tourist routes crosses the Park with the total distance of 85 km. In the Park there are numerous monuments including the 17th-century wooden church, the 19th-century manors and the ruins of the castle built in 1827 on the island on Lake Góreckie.
In 1993 the Natural Landscape Park of the Zielonka Forest was established in the neighbourhood of the city in order to preserve and protect the forest complex of great natural, and scientific-and-didactic value.
The areas of the Poznań's 19th-century fortifications are the bats refuge in the wintertime and have been subject to protection as the Natura 2000 Areas. Along the northern city limit there was a military training field on the left bank of the Warta River which was also included in the Natura 2000 network as the habitat of many species of flora and fauna. A considerable part of this refuge lies within the limits of the Biedrusko Area of Protected Landscape. In the immediate neighbourhood of the city there is also the Wielkopolska Reguge, protected as the Natura 2000 Area, which is the habitat of many mammals, reptiles, amphibians, fish and invertebrates.
Near the south-east border of Poznań there is the Radojewo park and landscape complex. For several years efforts have been made to cover this area with protection as the natural reserve under the name of Kokoryczowe Wzgórze (the Corydalis Hill).
25 natural monuments are located in the city. Most of them are trees: 12 single specimens, and 10 clusters and alleys which comprise the total number of nearly 1000 trees. The list is completed by 3 scattered boulders.