THE NATIONAL NURSERYMAN 
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tant introductions from western China. It can best be 
seen in tlie Philadelphus Group on the Hussey Hill Road 
opposite the Lilacs. 
Philadelphus inodorus. This native of the southern 
Appalachian foothill region, although the flowers are 
without fragrance, is for many persons the most beautiful 
plant of the genus. It is one of the medium-sized 
species with gracefully arching stems and pure white, 
cup-shaped flowers from an inch and a half to two inches 
in diameter. It is not often seen in gardens, although 
it was one of the first species of Philadelphus cultivated 
in Europe where it was first seen about the middle of the 
eighteenth century. The plants in the Shrub Collection 
and in the Bussey Hill Group are now covered with 
flowers. 
A double-flowered Philadelphus. A Philadelphus 
raised by Lemoine and called by him Argentina is flower¬ 
ing for the first time on Bussey Hill Road. It is still a 
small shrub with erect, rather rigid stems now covered 
with large semi-double flowers which look like small 
white roses. More curious than beautiful, this addition 
to summer-flowering garden shrubs will perhaps he 
valued by persons who admire floral monstrosities. 
Aesculus ITarbisonii. This interesting plant which 
unfolds its leaves later than any other in this group and, 
with the exception of A. parvifolia, is the last to flower, is 
now blooming near the other dwarf Buckeyes. Two in¬ 
dividuals of this peculiar plant appeared here in 1905 
among a number of seedlings of A. georgiana and are be¬ 
lieved to be hybrids of that species and the red-flowered 
variety of A. discolor , the two species growing together 
where the seed was gathered near Stone Mountain in cen¬ 
tral Georgia. The leaves of this hybrid are lighter green 
than those of either of its supposed parents; the flowers 
are borne on stout red stems in broad red panicles and are 
about three-quarters of an inch in length with a rose- 
colored calyx and canary yellow petals tinged with red 
toward the margins. The hybrid origin of these plants 
is shown by the fact that glands and hairs are mixed to¬ 
gether on the margins of the petals, hairs only being 
found on the margins of the petals of plants of the group 
of Aesculus to which A. georgiana belongs and only 
glands on those of the plants of the group to which A. 
discolor belongs, so that when both hairs and glands are 
found on the margins of the petals of one of the Buckeyes 
it is good evidence that the plants are of hybrid origin. 
Cornus racemosa. This northern Cornel has been 
largely used in the Arboretum in roadside plantations and 
is now conspicuous as the plants are covered with their 
small clusters of creamy white flowers. These later in 
the season will be followed by white, translucent fruits 
borne on bright red stalks. This Cornel blooms here 
with some of the native Roses and their pink flowers com¬ 
pose perfectly with the white flowers of the Cornel; and 
when these plants are used together, as along some of the 
Arboretum* roads, delightful effects are obtained. 
.Tune-flowering Hydrangeas. For a quarter of a 
century Hydrangea Bretschneideri. a native of northern 
China, has been a favorite plant in the Arboretum. It is 
a large and vigorous shrub with dark green leaves and 
flat heads of fertile flowers surrounded, as in oilier 
species of Hydrangea, by a ring of pure white ray flowers. 
The largest plant of this Hydrangea in the Arboretum is 
at Mr. Dawson’s house on Centre Street. Several of the 
Hydrangeas introduced by Wilson from western China 
are now in flower in the collection of Chinese Shrubs on 
Bussey Hill and lor the first time show their real value 
as garden plants in this climate. The tallest and most 
vigorous of these plants is Hydrangea Rosthornii , which 
is already eight feet high, with flower-clusters eight 
inches across. II. xanthoneura is closely related to II. 
Bretschneideri and can only he distinguished from it by 
a slight variation in the shape of the leaves, and by the 
almost entire absence of hairs from their lower surface. 
The plants are now covered with flower-clusters which 
are about eight inches across. Two forms of this Hy¬ 
drangea, var. Wilsonii and var. setchuenensis are also in 
bloom, and as garden plants are as valuable as the species 
itself. 
Hydrangea petiolaris. There are now few hand¬ 
somer plants in the Arboretum than the specimen of this 
climbing Hydrangea on the Administration Building, al¬ 
though the long-stalked white ray flowers which sur¬ 
round the clusters of fertile flowers are beginning to fall. 
There are about a hundred of the flower-clusters on the 
plant and many of them are eight or nine inches across 
and terminal on short lateral branchlets which stand out 
from the body of the plant and give it an irregular sur¬ 
face which adds to its beauty. This Hydrangea is cer¬ 
tainly the best deciduous-leaved climbing plant which 
can be grown against brick or stone walls in this climate. 
Potentilla fruticosa Veitchii. This white-flowered 
lorm of the widely distributed yellow-flowered Cinquefoil 
is an excellent garden plant in this climate. It is dwarf 
in habit, blooms freely every year, and the plants are 
covered with flowers during several weeks. It can be 
seen in the general Shrub Collection and with the other 
Chinese shrubs on Bussey Hill. 
Potentilla tridentata is an excellent little rock gar¬ 
den shrub not often seen in cultivation. It is a native of 
eastern North America where, especially on the coast, it 
is common in rocky and exposed situations. The leaves 
are composed of three leaflets which are dark green and 
very lustrous, and the small white flowers are produced 
in several flower-clusters standing well up above the 
plant on long stems. This is well established in the gen¬ 
eral Shrub Collection where it is now flowering. 
According to information received from the United 
States Department of Agriculture there is an outbreak 
of the true army worm in Maryland, Virginia. District of 
Columbia and other Atlantic States. 
They recommend as soon as discovered spraying with 
a solution of arsenate of lead. 2 pounds to 50 gallons of 
water, or Paris green I pound; freshly slaked lime 2 
pounds and 50 gallons of water. 
