Sweetgum

Liquidambar styraciflua - the spiky fruits of the American Sweetgum. 

In pencil - with a diameter of 18". 

Abstracted and repeated.

Photoshopped into art museums*.

*thanks to Martin

Milkweed

Milkweed pods. In pencil - three foot giants on my easel - and in watercolor (8.5" x 11"). Almost all of the seeds blown away.