Archaeologists in northwestern China have unearthed a 2,500-year-old skeleton wrapped in a "shroud" made up of well-preserved marijuana.

Found during an investigation of the Jiayi Cemetery in Turpan, which houses 240 ancient tombs, the burial contained "an extraordinary cache" of 13 Cannabis plants.

The three-foot long, locally produced plants, were arranged across the chest of a man who died at around age 35.

"The Cannabis plants were placed above the body trimly, in a way that suggests ritual-medicinal purposes," Hongen Jiang of the Department of Archaeology and Anthropology at the University of Chinese Academy of Sciences in Beijing, told Discovery News.

The man was laid down on a wooden bed with a reed pillow under the head, while 13 nearly whole female Cannabis plants were deposited diagonally across his body, with the roots and lower parts of the plants grouped together and placed below the pelvis.

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"The stems and foliage were arranged in a parallel alignment extending upwards to just under the chin and along the left side of the face," Jiang and colleagues wrote in the journal Economic Botany.

Radiocarbon dating of the tomb's contents, including the cannabis plants, indicates the burial occurred sometime between 2,400 and 2,800 years ago.

While all of the plants had roots attached, most of the flowering heads had been cut off. The few flowers that remained were nearly ripe and contained some immature fruit, suggesting the plants were collected-and that the man was buried -- in late summer, around the end of August or early September.

The plants offer rare insight into ancient cultivation practices.

"Due to the extremely dry climate, the stems and foliage retained their characteristic natural shape although they had turned yellowish brown," the researchers said.

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They noted this is the first case of cannabis plants used a as a covering for a human body.

Examining the way the plants were lying on the man's body, basically pressed flat, the researchers concluded they had been fresh and harvested just before the funeral.

"Therefore, the plants were most likely growing locally," they said.

Jiang and colleagues suspect the plants were just harvested for their psychoactive resin. The Cannabis plants were all females with nearly ripe seed, and the flower heads contained the psychoactive resin of Cannabis.

"Our finding sheds new light on the ritual use of Cannabis in prehistoric central Eurasia, confirming that its use was widespread in the Eurasian steppe during the late Bronze to early Iron Age," Jiang said.

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