Biology and Ecology
The Eastern Pasque Flower (Pulsatilla patens) is a perennial herb with a strong branching rhizome and deep roots. During March and April, it attracts attention with its large light purple flowers with a high number of spirally arranged yellow stamens. When the flowers are fully flowering, palmately divided ternate leaves are developing. The shape of the leaves is an important character to distinguish P. patens from similar P. grandiflora. The determination of these two species is easier thanks to the fact that P. patens grows only in Bohemia and P. grandiflora can be found only in South Moravia. Pulsatilla patens differs from our most common P. pratensis subsp. bohemica by an erect funnelform perianths, while P. pratensis subsp. bohemica has dark purple bell-shaped declined flowers. The stem and leaves are densely hairy. After flowering, the stem elongates, allowing the hairy achenes to overgrow the surrounding vegetation and spread more easily through the wind.
The species belongs to the family Ranunculaceae and, like other representatives of this family, is highly toxic. It contains the glycoside ranunculin, which causes skin irritation and vomiting and diarrhea if ingested.
The Eastern Pasque Flower grows in dry to slightly wet grasslands, but also in forest fringes and openings, in shrubs and relict pine trees. These habitats belong mainly to the Festucetalia valesiacae community and Koelerio-Phleion phleoidis and Erico-Pinion associations. The species prefers west and north-facing slopes rather than the arid southern slopes. It grows most frequently on acid to very acid shallow stony soils that are well permeable for water.