Effects of available nitrogen on numbers of native herbaceous plants in Aomori, Japan

• Many herbaceous plants are threatened with extinction due to decrease in grassland in Japan. The communities dominated by native herbaceous plants were mostly in soils with low available phosphate in notrthern Kanto area, where Andisols have developed (Hiradate et al., 2008).

• Available phasphte is usually limited in Andisols due to high
  aluminum contents, and its increases promote invasion and luxuriance of exotic herbaceous plants. We investigated the factors affecting herbaceous plant communities in Towada, Aomori, northern part of Japan, where Andisols have
  developed.