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油松经人工模拟失去一定量的１年生针叶后对第２年高生长、针叶长度有明显的影响：失叶越多，影响越大，经２ａ后其高生长虽仍有差异，但均可恢复到正常生长状态，而失去少量２～３年生针叶后的油松具有补偿和超补偿效应，失去１年生针叶后油松不具有补偿和超补偿效应。在松毛虫大发生年份，油松失去９５％以上１、２年生针叶后，３ａ后在立地条件好的松林可恢复到正常生长状态，在立地条件差的干旱阳坡，仍未恢复到原有的生长状态。
After losing a certain amount of 1-year-old needles by artificial simulation, Pinus tabulaeformis had a significant effect on height growth and needles length in the second year. The more leaves were lost, Can return to the normal growth state, while the loss of a small amount of 2 to 3 years after coniferous pine has compensation and overcompensation effects, loss of 1-year-old coniferous pine does not have compensation and overcompensation effect. In the year when the pine caterpillar occurred, the Pinus tabulaeformis lost more than 95% of its 1,2-year-old needles, and then returned to the normal growth state after 3 years in the pine forest with good site conditions. On the dry sunny slope with poor site conditions, Some growing state.