Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Remixed from a drawing in 'An Index to Deering's Nottinghamia Vetus et Nova', Rupert Chicken, 1899. The unit tile can be had by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
The base gradient edited so now more details are rendered.
Source Lazur URH