林业生产每年要求大量的高质量种子。为得到这些种子建立了几千公顷种子园,其中树龄最老的已经进入了结实期。实践表明,等量和丰富的结实不是经常可能的,所以迫切的问题是探索刺激开花结实的可能性。目前在拉脱维亚对种子园中的树进行了试验,已经得到了一定结果,表明了环剥、捆绑和切根对嫁接树的影响。1969年春,对8年生的松林进行了研究。环剥在0.5米高处切下5—7毫米的树皮,捆绑 Forestry production requires large quantities of high-quality seeds each year. Thousands of hectares of seed orchards have been established for the seeds, of which the oldest is already in the sturdy period. Practice shows that it is not always possible that isosceles and abundance of sturdiness, so the pressing issue is to explore the possibility of stimulating flowering robustness. Experiments on trees in seed orchards in Latvia have been carried out to date and some results have been obtained indicating the effect of girdling, bundling and rooting on grafted trees. In the spring of 1969, the 8-year-old pine forest was studied. Girdle cut 5-7 mm bark at 0.5 m height, tied