Blue grass
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"Blue grass" is a title based upon conjecture.
Check the behind the scenes section, the revision history and discussion page for additional comments on this article's title.
Blue Grass was a form of grass that grew in 2020 Wales. It turned blue because of minerals being unearthed by Silurians. This got the attention of the The Doctor, who realised something was wrong. (DW: The Hungry Earth)