Cypress spurge is the common name of euphorbia cyparissias. It has many short, plume like branches. It is native to Europe. It is naturalized and a weed in the United States.
GalleriesFlowers and Shrubs: C
L. H. Bailey Standard Cyclopedia of Horticulture (New York, New York: The MacMillan Company, 1917) volume 2, page 1173