Potentilla longibracteata, also known as Castle Crags ivesia and longbract mousetail, is a rare species of flowering plant in the rose family.[1] It is endemic to Shasta County, California, where it is known only from Castle Crags. It grows in rocky granite habitat in the temperate coniferous forest.
Potentilla longibracteata is a perennial herb forming a glandular green tuft of foliage where it grows from crevices in granite rock. The leaves are 2 to 4 centimeters long and are made up of several pairs of lobed leaflets. The inflorescence is a headlike cluster of several flowers 1 or 2 centimeters wide. Each flower is just under a centimeter long and has tiny pale yellow petals.