Kiyasho

…the guardian of the kiyashio (lumberyard), a place where timber for the construction of powerful families, temples, shrines, government offices, etc. was collected and processed. During the Nara and Heian periods, the construction and repair of large temples and shrines, the mansions of powerful families, and other structures continued without rest, and the collection of timber was essential for this. …

*Some of the terminology explanations that mention "Kiyadokoro" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…権門，寺社，官衙などの造営用材木の集積･加工場所たる木屋所（きやしよ）の番人。奈良･平安時代，大寺社や権門勢家の邸宅などの造営，修理がやすむことなく続けられたが，それには材木の集積が不可欠であった。…

※「木屋所」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報