This section is from the book "The Native Flowers And Ferns Of The United States ", by Thomas Meehan. Also available from Amazon: The Native Flowers and Ferns of the United States in Their Botanical, Horticultural, And Popular Aspects.
Potentilla Fruticosa, L
Stem erect, shrubby,two to four feet high, very much branched; leaves pinnate; leaflets five to seven, closely crowded, oblong-lanceolate, entire, silky, especially beneath; stipules scale-like; flowers numerous, yellow, terminating the branch-lets. (Gray's Manual of the Botany of the Northern United States. See also Wood's Class-Book of Botany.)
CCORDING to Dr. Gray, the name of the genus Potentilla is "a kind of diminutive from potens, powerful, alluding to the reputed medicinal power, of which, in fact, these plants possess very little, being merely mild astringents, like the rest of the tribe." Almost every common plant had some great virtue attached to it by the people of the olden time, and for this one it was claimed that "it is good against all sorts of agues and fevers, whether Continent, Continual, or Contermitting: whether they be burning fevers only, Malign or Pestilential. It cools and attemperates the blood, and Humors, and is an excellent thing for a Lotion, Injection, Gargle, and the like, for Sore Mouths, Ulcers, Cankers, and other corrupt, foul, and running Sores. The juice mixt with a little Honey, prevails against Hoarseness, as also the Cough of the Lungs." These are some of the reputed powers to which Dr. Gray refers, and which suggested the present botanical name of the family. In old writers we find the appellations Pentaphyllum and Quinquefolium, Greek and Latin names, respectively, for "five-leaved," the leaves of most of the species being in fives, and the present common name, "Cinque-foil," is, of course, identical with these. But the orthography of the latter is French, and it is a matter of surprise that a plant, so common in England as is the Cinque-foil, in numerous forms, should yet seem to have had no distinctively English name whatever.
Most of the Potentillas, or Cinque-foils, are creeping plants, or herbaceous plants, with evergreen foliage, such as is the strawberry plant, to which family, indeed, the Cinque-foils are closely allied; but the Potentilla fruticosa takes on a woody character, and becomes a small bush, and in this is an exception to all the rest of the family, of which there are nearly a hundred species. Some botanists have, indeed, tried to make several species out of the one now under discussion. In Europe, where it also grows wild, it has long been known; and when Pursh came to this country, in the beginning of the present century, and found the plant here, he believed it to be distinct, and named it Potentilla floribunda. Nestler also thought the Russian plant distinct from the general European form, and called it P. davurica. Schlechtendal again names a kind with narrow leaves P. tenuifolia. But the best authors in Europe, and all in America, agree in considering all these forms as mere varieties of our present P. fruticosa.
The student will notice, on examining the circuit of the leaves round the stem of Potentilla, that five leaves form a complete circuit, or a verticil, and he will perceive the operation of the same law in the formation of the flower, which is, indeed, nothing but a suddenly arrested branch, the petals and sepals being transformed leaves. He therefore finds a double row of sepals of five each, and five petals in the flower, and the stamens generally some multiple of five. When any of the number is wanting in these cases, it is generally because the convolving and depressing growth has been so rapid as to entirely obliterate some of the petals, or in botanical language, because they have disappeared by abortion. The gradual retardation of the wave growth is very prettily illustrated here. Although most Cinque-foils have but five leaflets, the Shrubby Cinque-foil has often seven; but when growthforce is about to be arrested by reproductive force, only five are formed, and then, successively, only three, two, and one. Thus it appears that the rapid convolutions, which end in the verticils forming the flowers, occur only when the growth-force has been reduced to the production of single leaflets instead of full leaves. If the same thing were to occur before, at the three or five leafleted condition, the probability is that the petals would each be three or five lobed instead of entire, as we see them now. There is also some special interest in the calyx, which, as we have said, is composed of a double verticil of five leaves each. The outer set remains somewhat spreading, but the inner is bent inwards, making a slight covering for the naked seeds (Fig. 3). The result is a very pretty design for ornamental work, as shown in our full-face view of the capsule in Fig. 2. The seeds in this species of Cinque-foil have likewise a special interest of their own. In some of the allied Potentillas, the styles are thickened upwards, being what is technically called "clavate" or "club-shaped"; but our species, with a few others, has them filiform, so that, after the petals have fallen, the seeds look as if they were covered by a growth of thin hair. On this account, Torrey and Gray grouped these species together in a separate subdivision, with the expressive name, Comocarpa, coma signifying a head of hair.
Potentilla fruticosa is also interesting from a geographical point of view. It is widely diffused over the northern regions; and if we allow the several forms alluded to above to be simply varieties of the same species, we may say that it makes a circuit completely round the globe. It is abundant in Maine, Massachusetts, and Connecticut, decreasing in extent through New York till it reaches a southern limit in Northwestern New Jersey. We know of no locality where it is wild in Pennsylvania, although not uncommon there in half-cultivated places. In its New England locations, it seems to prefer low, wet meadows. In Ohio, it is found in dryer situations. When it reaches Michigan, it loves to grow among the sand on the lake shores; but as it travels farther into the State, it is found on dry, rocky places in the dells. In Colorado, it grows in extremely dry localities, both in the foot-hills and high up in the mountains, and it continues in this way to vary its conditions until it reaches California, where, according to the geological survey of that State, it is found in Ebbetts Pass, in the Sierra Nevada, and thence takes its march northward to Siberia. In Wyoming, Dr. C. C. Parry tells us that, with a few other rosaceous plants, it forms almost all the shrubbery they have in that treeless region; but it is only a small shrub, rarely exceeding two feet high in our gardens, where it is very easily grown and very welcome on account of its profusion of bloom from July till October, and at a season of the year when few other shrubs give us any flowers.
In some parts of Connecticut, it has found the soil and climate so much to its liking that it takes complete possession of the ground, to the great annoyance of the agriculturist. It is called "Hard Hack" in those parts; but as this name is better known in connection with Spirted tomentosa, there is no reason why it should supersede Shrubby Cinque-foil. Dr. I. H. Hall, however, in the "Bulletin of the Torrey Botanical Club," Vol. I, says that it is the P. arguta which the people of Connecticut call "Hard Hack," and which is so bad a weed there.
It is said to be a remarkable fact that, although all other animals will eat Potentilla fruticosa greedily, hogs cannot be persuaded, under any circumstances, to touch it. We have not been able to verify this from experience, and so give it as part of existing history, subject to future experiment; for in these matters repetition of observations does no harm. In some parts of Europe, brooms are made of the branches, which are said to be equal to heath or birch, but the plant has no known use in this country.
1. A flowering branch.
2. Calyx in full-face view, showing its beauty fur ornamental designs.
3. Calyx, showing the live indexed,.upper sepals.