450 



Garden and Forest. 



[September i8, 1889. 



would, i)rol)al)ly, 1)0 even more apparent than they are here. 



The beauty of ;ill Lindens is great and incontestable. In 

 the case of the Crimean Linden, this beauty is heightened by 

 the lustre of the leaves, which resemble those of the Beech. 

 It also has the advantage of Ijlooming as late as the last week in 

 July. The tree must attain a considerable age l.iefore it blooms, 

 which it did in Berlin for the Hrst time in 1873. My trees at 

 Schru-fenberg are fruiting well this year, and we shall have 

 an abimdance of seed. 



We have here, also, some specimens of a variety of Tilia 

 platyphylla, which is remarkable for the yellow color of its 

 N'oung branches and buds, a peculiarity which disappears in 

 summer, but is very noticeable in winter and early spring. 

 This is the variety known as Aurea. I mention it here be- 

 cause I have learned something as to its origin. It was dis- 

 covered l^efore 1829 in a forest of Alsace, near the outskirts 

 of Bollwiller, by M. Baumann, who also first distributed it. 



Bei-Iin. C. Bollc. 



Cultural Department. 

 Notes on Hypericums. 



THE H}'pericums, or St. John's-worts, embrace more than 

 160 described species of herbaceous and woody plants, 

 and there are, probably, a good many more still unknown. 

 Of the known species only a comparatively small number are 

 of much value to the florist or gardener, although all may be 

 interesting or lieautiful from the botanist's point of view. 

 E.xcept in very rare cases, in which the blossoms are white, 

 the flowers of all the species are yellow, and they vary in size 

 from very minute ones on slender annuals, an inch or two 

 high, to the large golden yellow blossoms, several inches in 

 -diameter, of some of the cultivated species. 



They are chiefly found in North America, Europe and Asia; 

 but a few are tropical, and some inhabit the southern hemi- 

 sphere. In Europe a few of the tender species are thought 

 worthy of green-house culture. The name of St. John's-wort 

 is said to have been derived from the fact that the common 

 people of some European nations, especially the English and 

 Germans, used to gather large quantities of the flowers and 

 ornament their dwellings with tiiem on St. John's Day, as a 

 supposed protection from evil spirits. The species chiefly 

 used for this purpose and to which the name was hrst given 

 was the common St. John's-wort (^Hypericum perforahnn), 

 which is found all over Europe and a large part of Asia, and 

 which, having become naturalized in America and spread 

 over a large area, is now looked upon here as a troublesome 

 weed. It is a perennial herb, and when in full bloom is cer- 

 . tainly as handsome as some of the occasionally cultivated 

 herbaceous or half-shrubby species. The deep yellow 

 flowers, in large corymbs, are over an inch in diameter and 

 crowned with many stamens, and the leaves have very dis- 

 tinct pellucid dots, which are plainly seen when held up to 

 the light. These dots on the leaves are characteristic of this 

 genus, but they vary in number and size on different species, 

 and are often black instead of pellucid. They secrete aro- 

 matic resinous juices and a volatile oil. 



The Hypericums are generally not difficult to cultivate and 

 propagate, yet very few classes of hardy ornamental plants 

 are so little known and so poorly represented in American 

 gardens generally. Some of the group are particularly valu- 

 able, because they flower after most shrubs and early sum- 

 mer-blooming perennials have past their best condition, and 

 before other autumn flowering kinds have developed much 

 of their efflorescence. 



A number of shrubljy and half-shrubby species of Hyperi- 

 cums, grown in England and the warmer parts of Europe, 

 cannot be relied upon for hardiness to withstand the win- 

 ters of our New England or Northern states. But among 

 those tested at the Arnold Arboretum are some which are 

 thoroughly satisfactory,, and others that have promised well 

 in the short time that they have been in the collection. Tiiey 

 have been grown in an exposed situation where there was 

 little protection in winter and no shade in summer, and 

 where it was, perhaps, too wet in winter and spring to give 

 the best results. 



Of the low-growing, half-woody species, Hypericum caly- 

 cinum is decidedly the most interesting and satisfactory. The 

 stems are less than a foot high, and although killed back to 

 the ground every winter, new flowering shoots arise from the 

 creeping, woody rootstocks. The large, smooth, green leaves 

 are ovate or oblong, and have very small, pellucid dots. 

 Rarely more than one flower is developed at the top of each 

 stem. The handsome flowers are bright yellow, from two to 

 three inches in diameter, and crowned with many long sta- 



mens. This species is easily propagated by root-cuttings, or 

 cuttings of ripe wood in late summer. The roots spread and 

 ultimately make large clumps, and the plants will thrive very 

 well either in the open sunlight or under trees, if the soil is 

 not too poor. In the Arboretum this Hypericum begins to 

 flower early in July, is in its best condition during that month, 

 and bears a few flowers in August, or even later. It is a 

 native of south-eastern Europe. This and all the other 

 Hypericimis bloom later and for a longer time if grown in a 

 cool, partly shaded place. 



Hypericum hirciniim, though not so handsome as the pre- 

 ceding species, is-a very free bloomer and is easily cultivated. 

 The stamens are very long and of varying length, the longest 

 being about one and one-half times the length of the broad, 

 pale yellow petals, which are three-quarters of an inch long. 

 The stems are killed almost to the ground in winter, and 

 come up again each year to nearly two feet in height. It 

 begins to flower about the second week in July and continues 

 until near the end of August. The form known as the Minor 

 variety is simply smaller and more compact in every way, 

 and it seems to flower somewhat later. 



H. 7>iuliifloruin grows taller than the last species, which it 

 much resembles in foliage and flower. It is more shrubby, 

 but its blooming season is shorter, lasting for only about two 

 weeks in July. 



H. oblongffoUinn, a native of high altitudes of the Hima- 

 layas, has not proved very hardy, but should be further tested. 

 It has large leaves and very handsome, golden-yellow flowers 

 from two' to three inches in diameter. Another Asiatic spe- 

 cies is H. patuliim, with somewhat smaller leaves and flowers. 

 It has usually proved hardy, but, with some others, was killed 

 last winter. H. AndroscEmum, the Tutsan or Sweet Amber of 

 England, requires further proof of hardiness before it can be 

 recommended here. Some of these species, as well as some 

 others, may thrive with little care in tlie climate of the middle 

 states or further south, but here they require a good deal of 

 protection in order to give very satisfactory results. 



But among the thirty known North American species are 

 several which are perfectly hardy and also very bright 

 and effective as ornamental garden shrubs. By far the 

 best of these is the beautiful Hypericum aureu?n, of which 

 a description and figure were given in a recent number 

 of Garden and Forest (pp. 184 and 185). In cultivation 

 it is a bushy, very much branched shrub, three to four 

 feet high, and often more in diameter. Several flowers 

 are usually produced on the end of each branch and branch- 

 let, although in a wild state the flowers are often solitary. 

 The flowers ai-e an inch and a half, or sometimes nearly two 

 inches in diameter, and the petals are very thick and firm, and 

 pale yellow or orange in color. The stamens, of which a 

 careful count shows a thousand in a well-developed flower, 

 are a little more than half the length of the petals, and of a 

 golden-yellow color. When the flower is first open the sta- 

 mens are so arranged that they have a beautiful dome-like 

 shape, but, after repeated visits by l.)umble-bees, which eagerly 

 collect the pollen, the stamens lose their anthers, become m.ore 

 spread out, and have something of the appearance of a broad 

 square-faced brush. The color gradually changes to an 

 orange-brown, and after the third or fourth day the filaments 

 becofne brown and are ready to fall with the first wind or rain. 

 Although a native of Tennessee and other southern states, 

 this species proves perfectly hardy about Boston, where it 

 continues blooming from the first or second week in July 

 until the middle ct August, or later if the plants are young, or 

 are grown in a moist or partly shaded place. 



Hypericum prolijicum is a species found from New Jersey 

 southward, and also westward in Minnesota, Illinois, etc. It 

 is the American species which is perhaps most commonly 

 cultivated in European gardens. Between tliis species and 

 H. Kalmianiim there appears to be no very great choice as to 

 ornamental value. The latter was originally found in the 

 vicinity of Niagara Falls, and extends over the region about 

 the Great Lakes, and within a few years it has been re- 

 ported from Middle Tennessee. In its native habitat it varies 

 in size from a few inches in height in exposed places to a 

 couple of feet or more in favorable situations. In cultivation 

 it will grow about as large as H. prolijicum which attains a 

 height of three feet or more. Both species are cjuite hardy. 

 Perhaps H. Kalmiajium being found so far north would do 

 best in localities where the winters are very severe. The 

 leaves are narrow, one or two inches long, and the thin 

 petalled golden-yellow flowers are about an inch across, and 

 produced in single or compound clusters at the ends of the 

 branches. The leaves of H. prolijiciun are usually larger, and 

 the flowers more numerous, though somewhat smaller, than 



