Seedlings of Brachypodium sylvaticum (Huds.) Beauv., Festuca gigantea (L.) Vill., Lolium perenne L. and Urtica dioica L. were grown on freshly collected soil from the upper horizons of an uncultivated rendzina and a brown forest-soil. All species responded to addition of a soluble phosphate on both soils but, while there was no response to the addition of apatite on the rendzina, there was as large a response to apatite as to soluble phosphate on the brown forest-soil. Brachypodium sylvaticum and Urtica dioica were also grown in sand-culture without phosphate, with a soluble phosphate, and with humus which is rich in organic phosphate. Both species responded to soluble phosphate but showed no response to the presence of humus. The experiments imply that even Brachypodium sylvaticum, which may occur naturally on calcareous soils containing only traces of soluble phosphate, cannot obtain phosphate from either apatite or humus when the pH is above 7.0.