thinning

noun

Process of removing plants or parts of plants to facilitate the growth of other plants
“The trimming, pruning and thinning must be managed with care. Some need more thinning than others.”
Wood, leaves, or other plant parts removed during the process of thinning
“but with a suitable mixture of early and late maturing kinds, the young hickories, ashs and larches can be utilized as thinnings, at a profit. In estimating the value of the thinnings upon the basis of Prof. Sargent's estimate of the acreage yield of hoop poles from hickory plantations,”
The action or result of reducing thickness, density, or number
“It is highly likely that this thinning was not atrophic or pathological, but simply the thinning from stretching under the forces of labor, as Bandl and others explain it.”