Sif is one of the Norse goddesses who embodies the earth, and as such she has been called the Earth Mother by some of her followers, though she doesn't personify the life force of the planet as does Jord (the Norse identity of Mother Earth, known to Greek mythology as Gaea and to modern popular culture as Mother Nature). Nevertheless, Sif can be considered a goddess of agriculture, as she has been associated with crop fertility, as well as concepts such as wedlock. She is well known for her dazzling golden hair, said to be representative of fields of golden wheat that served as a frequent food crop to the ancient Norsemen, which is the basis for one of the major myths involving a conflict between her husband, the thunder god Thor, and Loki, the god of mischief. Wanting to play a prank on Sif so as to render a blow to her pride over her beautiful golden locks, Loki sneaked into Sif's bedroom when she slept one evening and removed all of her hair. Devastated upon waking up and discovering what had been done, Sif immediately told her husband Thor, who instantly realized Loki's characteristic hand in such a cruel prank. Thor angrily confronted the Trickster god, demanding that he make recompense to Sif, "or else." Realizing that an angry Thor was not to be trifled with, Loki visited one of the dwarves, the diminutive race of beings who are masters at creating any number of useful objects for the deities out of their forges. After a bargain was struck, the dwarf smith created a headpiece of artificial golden hair that, when applied to Sif's head, magickally took root to her scalp and effectively replaced her missing locks.
Sif is said in the myths to have birthed the warrior goddess Thrud with her husband Thor (his sons Magni and Modi were birthed by his giantess lover, Jarnsaxa), and is also said in some sources to be the natural mother of Ull, the god of winter sports, by an unknown father.
Sif is a terrific goddess to call upon for achieving a degree of plentifullness and bounty in your life in a general sense, as well as forging a strong bond with the forces underlying the earth. I plan on making a strong effort towards building a spiritual bond with her in the future, as doing so is tantamount to building a stronger bond with the underlying forces of the earth itself.