White and Greenish 



Whorled or Green-flowered Milkweed 



{Asclepias verticillata) Milkweed fiimily 



Flowers — White or greenish, on short pedicels, in several small ter- 

 minal clusters. Calyx inferior ; corolla deeply 5-parted, the 

 oblong segments turned back ; a 5-parted, erect crown of 

 hooded nectaries between them and the stamens, each shorter 

 than the incurved horn within. Stem : i t0 2>^ ft. tall, simple 

 or sparingly branched, hairy, leafy to summit, containing milky 

 juice. Leaves : In upright groups, very narrow, almost thread-, 

 like, from 3 to 7 in each whorl. Fruit : 2 smooth, narrow, 

 spindle-shaped, upright pods, the seeds attached to silky 

 fluff; I pod usually abortive. 



Preferred Habitat — Dry fields, hills, uplands. 



Flowering Seaso?i — ^^j uly — September. 



Distribution — Maine and far westward, south to Florida and Mexico. 



In describing the common milkweed (pp. 135-138), so many 

 statements were made that apply quite as truly to this far daintier 

 and more ethereal species, the reader is referred back to the pink 

 and magenta section. Compared with some of its rank-growing, 

 heavy relatives, how exquisite is this little denizen of the uplands, 

 with its whorls of needle-like leaves set at intervals along a slender 

 swaying stem ! The entire plant, with its delicate foliage and 

 greenish-white umbels of flowers, rather suggests a member of 

 the carrot tribe ; and much the same class of small-sized, short- 

 tongued visitors come to seek its accessible nectar as we find about 

 the parsnips, for example. When little bees alight — and these 

 are the truest benefactors, however frequently larger bees, wasps, 

 flies, and even the almost useless butterflies come around— their 

 feet slip about within the low crown to find a secure lodging. As 

 they rise to fiy away after sucking, the pollen masses w hich have 

 attached themselves to the hairs on the lower part of their legs 

 are drawn out, to be transferred to other blossoms, perhaps to-day, 

 perhaps not for a fortnight. Annoying as they may be, it is 

 very rarely, indeed, that an insect can rid itself of the pollen masses 

 carried from either orchids or milkweeds, except by the method 

 Nature intended ; and it is not until the long-suffering bee is out- 

 rageously loaded that he attains his greatest usefulness to milk- 

 weed blossoms. "Of ninety-two specimens bearing corpuscula 

 of Asclepias verticillata," says Professor Robertson, "eighty-eight 

 have them on hairs alone, and four on the hairs and claws." And 

 again : "As far as the mere application of pollen to an insect is 

 concerned, a fiower with loose pollen has the advantage. But the 

 advantage is on the side of Asclepias after the insect is loaded with 

 it. It is only a general rule that insects keep to flowers of a particular 



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