About Platanthera bifolia
Linnaeus writes in his herbal book from 1725 that because the flowers fragrances at night he believed that it is because it will tell us what is going to happen night times, and tubers are an excellent afrodisiac for older men. Platanthera bifolia can be up to 50 cm high and has two roughly equal leaves. In the north it can often have only a leaf. Platanthera bifolia have up to 30 flowers which are large and white with a spur up to 3 cm long, thin and regular thick. Pollini which is clearly visible, parallel and gathered. P. ssp. bifolia blooms almost simultaneously the P. clorantha. Probably all pollinating of moths (Sphingidae, Noctidae and Geometridae). Pollination mechanisms to Platanthera bifolia have different barriers that must be overcome for the pollination success. Here co-evolution gone different paths so that propagation arenas (rostrum) is different from P. clorantha and adapted to each their insects.
Thus, the cross-pollination between P.clorantha and P.bifolia counteracted. Should a hybrid arise its fragrance is not attractive to insects, and pollination of hybrids is therefore rare. Hybrids are the rule sterile but fertile against parental species and we therefore say that the hybrids are interfertile. It is estimated that if the hybrid is pollinating one of the species, its offspring be absorbed and equal to one of the species.
In Denmark, Dane S. Th. Dreyer already in 1842 aware that there may be two different types of ssp, bifolia, but this did not foothold among the Danish botanists and was last mentioned in a Danish flora in 1886. Upon further studies in the early 1970s came the discovery of S. th. Dreyer in 1842 into the light again and ssp. bifolia is now divided into two subspecies which are Platanthera bifolia ssp. bifolia and Platanthera bifolia ssp. latiflora. They can be difficult to distinguish one from another.