Planting Chinese pine in the loess hilly and gully region in rainy season

Compared with planted two-year-old seedlings of Chinese pine in spring time,the experimentation of planted two-year-old and one-year-old seedlings of Chinese pine in rainy time in the loess hilly and gully regions of northern Shaanxi Province had been done.The climate of 45 days from planted date and the soil humidity had been observed in spring time and rainy season.Harm status of rodent,Chinese pine's survival rate,and Chinese pine's growth status of four years from planted year had been investigated.The results showed that the precipitation in rainy season was more than that in spring time,the air relative humidity was higher,the evaporation of 26 days from the planted date was lower,and wind speed was lower;the air temperature,soil temperatures,and the soil humidity were higher in rainy season than those in spring time.The habitat in rainy season was benefiting the seedlings to revive and grow.The seedlings planted in rainy season had avoided rodent harm peak in spring time in the planted year,so the seedlings' survival rate was higher.From the planted year to four years later,the seedlings' survival rate planted in rainy season was higher than that planted in spring time,and the growth amount of two-year-old seedlings was more than that planted in spring time,that of one-year-old seedlings was almost same as that planted in spring time.Planted Chinese pine in rainy season could obviously improve seedlings' survival rate,and promote seedlings' growth.