New spring foliage will soon be obscuring the rusty red or light yellow stems of osier dogwood, Cornus sericea (or Cornus stolonifera). Because this odd dogwood is grown for these distinctively colorful stems instead of blooms, it can be pruned harshly before foliation, to promote more twiggy growth for next winter. Unpruned plants form thickets five to ten feet high and ten or more feet broad. The flowers are actually rather pathetic relative to those of other dogwoods, since they lack colorful bracts. Where exposed to frost, the opposing two or three inch long and one or two inch wide leaves can provide nice reddish autumn color.