樟子松、长白松、赤松和黑松的引种研究

以樟子松7个种子源的种子和长白松，赤松和黑松的种子在北京地区做引种试验，并以油松做对照。试验结果表明，长白松生长的表现较好，优于油松。赤松和黑松表现一致，不如油松。樟子松生长表现更差。但从樟子松不同种源来看，呼伦贝尔、大兴安岭南部和小兴安岭的种源生长表现要优于大兴安岭北部的种源。

Studies on Introduction of Pinus sylvestris var. mongolica, P. sylvestriformis, P. densiflora and P. thunbergii

With the contrast of Pinus tabulaeformis, the introduction tests of P. sylvestriformis, P. densiflora, P. thunbergii and P. sylvestris var. mongo-lica, which included seven provenances, were conducted in three locations (elevation ranges 50-820 m) in Beijing mountain area. The results show that the growth of P. sylvestriformis is superior to that of P. tabulaeformis and the other pines have no advantage in comparison with P. tabulaeformis. There is significant variation among different provenances of P. sylvtstris var. mongolica in growth. The seed sources of Hulunberier, The Xiaoxinan Mountains and the southern part of The Daxinan Mountains are better than those of the northern part of The Daxinan Mountains.