Yellow and Orange 



Long-branched Frost-weed ; Frost-flower ; 

 Frost-wort; Canadian Rock-rose 



{Helianthemum Canadense) Rock-rose family 



Flowers — Solitary, or rarely 2 ; about i in. across, 5-parted, with 

 showy yellow petals ; the 5 unequal sepals hairy. Also 

 abundant small flowers lacking petals, produced from the 

 axils later. Stem: Erect, } in. to 2 ft. high; at first simple, 

 later with elongated branches. Leaves: Alternate, oblong, 

 almost seated on stem. 



Preferred Habitat— \^xy fields, sandy or rocky soil. 



Flowering Season — Petal-bearing flowers. May — July. 



Distribution — New England to the Carolinas, westward to Wis- 

 consin and Kentucky. 



Only for a day, and that must be a bright sunny one, does the 

 solitary frost-flower expand its delicate yellow petals. On the 

 next, after pollen has been brought to it by insect messengers 

 and its own carried away, the now useless petal advertisements 

 fall, and the numerous stamens, inserted upon the receptacle 

 with them, also drop off, leaving the club-shaped pistil to develop 

 with the ovary into a rounded, ovoid, three-valved capsule. 

 Notice how flat the stamens lie upon the petals to keep safely 

 out of reach of the stigma. Another flower, exactly like the first, 

 now expands, and the bloom continues for weeks. Why does 

 only one blossom open at a time } Because the whole aim of the 

 showy flowers is to set cross-fertilized seed, and when only one 

 at a time appears, pollination not only between distinct blossoms 

 but between distinct plants insures the healthiest, most vigorous 

 offspring — a wise precaution against degeneracy, in view of the 

 quantities of self -fertilized seed that will be set late in summer by 

 the tiny apetalous flowers that never open (see p. 108). Surely 

 two kinds of blossoms should be enough for any species; but 

 why call this the frost-flower when its bloom is ended by 

 autumn .? Only the witch-hazel may be said to flower for the 

 first time after frost. When the stubble in the dry fields is white 

 some cold November morning, comparatively few notice the ice 

 crystals, like specks of glistening quartz, at the base of the stems 

 of this plant. The similar Hoary Frost-weed (//. majus), whose 

 showy flowers appear in clusters at the hoary stem's summit, in 

 June and July, also bears them. Often this ice formation assumes 

 exquisite feathery, whimsical forms, bursting the bark asunder 

 where an astonishing quantity of sap gushes forth and freezes. 

 Indeed, so much sap sometimes goes to the making of this crystal 

 flower, that it would seem as if an extra reservoir in the soil must 

 pump some up to supply it with its large fantastic corolla. 



317 



