This lecture carefully explains the basic technique of leaf thinning for Japanese Black Pine. It provides specific guidelines: for each bud, leave only three pairs of needles on vigorous buds, four pairs on medium-vigour buds, and five pairs on weak buds. Adjustment methods based on the strength of each bud are demonstrated. The focus is on cultivating the important “inner buds” to enhance the tree’s future structure through leaf thinning. Practical tips on the correct use of tweezers and techniques to avoid damaging needles are also thoroughly introduced.