The leaves of the Pussy Willow have a felt-like cast to them early in the season and retain it on the undersides for the rest of the year. These leaves host a number of butterflies and moths in moist, sunny habitats, most notably the Viceroy Butterfly. In natu ... re and in the yard, Salix discolor is a bit inconsistent in form, but it usually has a few larger limbs that are well branched. It can be anywhere between 8 and 15 feet tall. It is popular in spring for its fluffy gray and yellow catkins from where it gets its name.