Abstract
In the present study, the authors set up a deer exclosure plot in a secondary forest where the species had flowered and died in 2004 in Kyoto City's northern mountainous region, and examined Sasa veitchii var. hirsuta seedling growth inside and outside the plot from 2005 to 2010 to determine the effects of deer grazing on seedling regeneration. The results showed that culms and shoots of seedlings outside the exclosure increased in number from 2008 to 2009 and were significantly larger than those of seedlings inside the exclosure. However, culms and shoots of seedlings outside the exclosure decreased in number in 2010, and there was no significant difference in the numbers of those inside and outside the exclosure at this time. Values for the culm height, rhizome length and dry weight of seedlings outside the exclosure were significantly lower than those for seedlings inside after 2008. These values for seedlings outside the exclosure decreased in 2010 as compared to 2009.
The results of the study indicate that Sasa veitchii var. hirsuta seedlings become dwarfed and densified when exposed to deer grazing for a period of two years, and that they become seriously dwarfed and sparse when exposed for more than three years. The results also indicate that deer grazing decreases rhizome extension of Sasa veitchii var. hirsuta seedlings. This implies that continued deer grazing may cause extinction of Sasa veitchii var. hirsuta seedlings in the mountainous region of Kyoto City.
