Oyatsu-hime, written as "大屋都比賣神" or "大屋津姫命," is the goddess of trees in Japanese mythology. According to the "Nihonshoki" (Chronicles of Japan), her father is Susanoo, her older brother is Isotakeru, and her younger sister is Tsumatsu-hime. The district of Oya-cho in Ota City, Shimane Prefecture is named after Oyatsu-hime.
It is said that Susanoo ordered her, together with Isotakeru and Tsumatsu-hime, to sow the seeds of trees on mountains all over the country, and after that, she went back to Kii Province (present-day Wakayama Prefecture) and lived there.
She is enshrined in Oyatsuhime-jinja Shrine in Utamori, Wakayama City, Wakayama Prefecture. One of the Chinese characters in her name means 'home,' which indicates that, as well as the goddess of trees, she is also the goddess of things made of wood including buildings, homes and ships.
She is also the goddess of reproduction, because her sowing of seeds all over the country represents women's ability to give birth. Today, she is worshiped as the goddess of forestry and the construction industry, along with her older brother, Isotakeru, and her younger sister, Tsumatsu-hime.
The fifth addendum to chapter eight in the first volume of the "Nihonshoki" mentions Oyatsu-hime in the following passage.
Susanoo said, "There is gold and silver in the islands of Karakuni (considered to be a part of present-day Korea), so it is not good that the country controlled by my children doesn't have any ships." Then, he pulled out some hairs of his beard and scattered them, and then, they turned into cedars. He continued pulling out some hairs from parts of his body. The hairs he picked from his chest turned into hinoki (Japanese cypresses), the hairs he picked from his buttocks turned into maki (Japanese yew pines), and his plucked eyebrows turned into camphor trees. After that, he decided on the use of each tree and suggested, "Cedars and camphor trees should be used for making ships, Japanese cypresses should be used for constructing palaces, Japanese yew pines should be used for coffins when the body is buried. Everyone should join together to sow seeds of many trees used for these various purposes and grow many more trees." Around this time, he had a son, Isotakeru, and two daughters, Oyatsu-hime and Tsumatsu-hime. These three gods contributed to sowing seeds and growing trees all across the nation, and then they moved to Kii Province (the southern part of present-day Mie and Wakayama Prefectures) where they were enshrined. After that, Susanoo finally entered Ne-no-kuni (underworld) via Kumanarinotake.
"Sendai Kujihongi" (Ancient Japanese History)
The "Chigi hongi" (Original Record of Earthly Deities) in chapter four of the "Sendai Kujihongi," a text that appeared in the Heian period but whose authenticity is disputed, mentions Oyatsu-hime in the following passage.
Susanoo had a son, Isotakeru and two daughters, Oyatsu-hime and Tsumatsu-hime. These three gods contributed to sowing seeds and growing trees all across the nation, and then they moved to Kii Province where they were enshrined. Susanoo and Amaterasu made a pledge to prove their sincerity (...) His next child was a son named Isotakeru, also called Oyahiko no Kami. After Isotakeru, he had two daughters, Oyatsu-hime and Tsumatsu-hime. These three gods were enshrined in Kii Province, which means the Kinokuni no Miyatsuko (governor or ruler of Kii Province) worshiped them devoutly as deities.