Abstract: Based on the investigation of some typical plantation forests and peripheral natural grasslands in a droughtprone semihumid area on the Loess Plateau, the analyses on meteorological conditions and the trial of shallow scarification of plantation land with fallen seeds and seedlings for regeneration were mainly regarded the factors affecting the natural regeneration of plantation forests. The results indicated that the germination of fallen seeds on land surface and seedling formation would be the key links for the natural regeneration of plantation forests under drought, in which water factor might be a dominant factor. Closely related to rainfall, the favorable aspects to ensure seedling occurrence for regeneration is snow cover accumulated in winter without thawing until early spring, and also precipitation lasting for a number of days or continuous rainy overcast appearing in spring or droughty season. Owing to successive scarcity of precipitation in winter and spring, it is difficult to emerge seedlings for regeneration in dry land. Nevertheless, to earth up may improve soil moisture conditions in dry land for fallen seeds and overcome the restriction of precipitation scarcity, thus the emergence of seedlings for regeneration may be improved. In order to stabilize the survival and growth of seedlings and achieve the natural regeneration of plantation forests, it is suggested to take some artificial measures.

Key words: plantation forest, natural regeneration, seedling, soil moisture, Loess Plateau