The "Willow" team at INRIA (a French research institute) frequently publishes papers on computer vision and surveillance. In their research, they use 1x1 grids as a standard "Bag of Features" representation to analyze video data.
There are specific video tutorials for creating a Paper Willow Tree using green and brown paper. Willow 1x1
"Willow" is a specific color name for American Olean's 1x1 abrasive or matte unglazed mosaic tiles. The "Willow" team at INRIA (a French research
You can find "Natural Willow" wood picture frames specifically in a 1x1 inch flat style. Willow 1x1
"Flocked Willow Paper" is a type of decorative paper sold for origami and other crafts.