As we have seen in the case of Abies stand, the stand forms will, also, be classified into the four types, that is, I_α, I_β, and II_γ, II_δ.
So far as I have observed in Cryptomeria stands, there are great many stands corresponding to the stand-type II_γ in different stages in Akita province, while for the stand type I_β, there are only the rudiment stages and for the stands of the stand-type I_α and II_γ, are now going to loss of sight. Because the stand corresponding to the stand-type I_α, gives the bigger logs and the better quality of timber than the stand corresponding to any other stand-type, while the stand corresponding to the stand-type II_γ, gives very poor appearance for the stand formation, something like a devastated one with reference to the stand corresponding to the stand-type I_α. In consequence of adjustment of the orders of stands in the working circle, the stand corresponding to the stand-type I_α, assumed as an over-mature one and the stand corresponding to the stand-type II_δ, assumed as a devastated one, are intended to be clearly cutted according to the principle of clear cutting system and of plantation. The stand corresponding to the stand-type I_β, though it was only the rudimental form, are now showing its appearance on the clear cutted area that has been carried on about 20-50 years ago.
On the cyclical changes of the stand formation for Cryptomeria stand, one can readily suggested from the history of forest management of Akita province in the federal ages. On this points, I would like to described in the other part, the forest management.
The explanations on the distributions of the diameters, heights and ages given in the previous section lead me to summarized as follows:
Lastly percetage, the number of trees in each stand type is as follows:

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