June 7, 1894. 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
451 
- Dwarf Gannas.— -What are known as Crozy’s _Cannas are 
favourite plants now. The magnificent varieties exhibited at the late 
Temple Show well represented this section in its best manner. For the 
guidance of those gardeners who had not the opportunity of inspecting 
these floral gems I have jotted down a few of the most striking varieties. 
The advantage of this type is its dwarf habit of growth, scarcely one 
plant wag beyond a yard high. The flowers are freely produced, and 
are decidedly attractive. Duchess of York, yellow, freely spotted with 
crimson ; Duke of York, the base crimson with a distinct golden edging ; 
Marguanti, deep terra cotta self; Charles Moore, red ground, heavily 
spotted, and clearly edged with yellow; Souvenir de Antoine Crozy> 
centre of the flower rich crimson, thinly edged with gold, a charming 
variety ; Cheshunt Yellow, rich yellow, most pleasing in point of 
colour ; and Trinignon Charlotte, crimson centre, broadly edged with 
gold, an exquisite variety.—E, M. 
- Ranunculus acris Poisonous.—M r. John W. Harshberger 
writes in the “ Botanical Gazette ” that Ranunculus acris must be 
added to the list of poisonous plants, or, at least, to those which irritate 
the skin. Specimens of this species, which had been in alcohol for 
more than a year, were distributed to a class in the University of 
Pennsylvania for study, and a day or two afterwards an intense itching 
sensation was experienced by all who handled them, while the skin 
between the fingers became red and covered with minute pustules like 
those produced from contact with Poison lyy. The acrid juice, which is 
universal in Ranunculaceous plants, and which is usually dissipated when 
dried, had been evidently extracted from the specimens, and when the 
alcohol evaporated the irritating principle was left on the hands. Mr. 
Harshberger adds that the fruits of the Poison Ivy and Poison Sumach 
are both eaten in large quantities by the crow, and one case is recorded 
where 153 seeds of Poison Ivy were found in one crow’s stomach ; while 
a single pound of dried excrement from a roost in the National 
Cemetery at Arlington contained 1041 seeds of Rhus Toxicodendron, 
341 seeds of Rhus venenata, besides 3271 seeds of other Sumachs, 
95 seeds of Juniperus virginiana, 10 seeds of Cornus florida, and 6 seeds 
of Nyssa sylvatica. 
- Manufacturing Ammonia. — According to an American 
contemporary, “ machinery is now being set up in Newark, New 
Jersey, for manufacturing ammonia from atmospheric nitrogen. Every 
gardener knows that nitrogen is one of the essential elements of plant 
food, and that it is far the most expensive of the elements that are 
required in fertilising mixturss. It is well known, too, that nearly 
four-fifths of the great ocean of air that surrounds the earth is nitrogen, 
and that it is practically useless as food to plants, although they are 
bathed in it all the time. Recent researches have shown, it is true, that 
a small portion of this nitrogen can be utilised by certain plants, espe¬ 
cially those belonging to the Leguminosse, but there never has been any 
available method of transforming the nitrogen of the air into plant food 
for general use. Of course it is not wise to expect too much from any 
reported discovery, but if it is true that the sulphate of ammonia can be 
produced by this new process at about one-quarter of its present cost, 
this will be one of the greatest boons that the science of chemistry has 
yet bestowed upon the art of agriculture. If ammonia can be cheaply 
manufactured from atmospheric nitrogen the discovery means that a 
great step has been taken toward securing a material increase in the 
productiveness of the soil.” 
- Measurement of White Pine.—M r. B. E. Fernow writes 
to the American “ Garden and Forest : ”—“ In the pursuit of an exten¬ 
sive series of measurements instituted by the Forestry Division for the 
purpose of ascertaining the rate of growth and production of White 
Pine and Spruce, one of our agents has just reported from Merrill, 
Wisconsin, the measure of a remarkable White Pine, a windfall, which 
had been thrown probably a number of years ago, as the sap-wood, 
mostly rotten, indicates. It measured 200 feet in length, 45 inches in 
diameter on the stump. As in the Census work of Professor Sargent, 
the range in height is given to 170 feet (52 meters), it might be interest¬ 
ing to record this unusual length of an old monarch. Altogether, the 
measurements of the acre-yield on the clay soil of the station, with a 
good humus cover, are worthy of notice. The height of the Pines, 
which are mixed with Hemlock and Birch, averages over 120 feet, not a 
few reach the height of 150 feet; the length of the timber—that is, of 
the merchantable part—exceeded in many of them 100 feet; the total 
amounts of timber contained on the acre are not as yet computed. The 
age is from 200 to 250 years ; the diameters are not extraordinary, and 
range from 30 to 36 inches.” 
- Dundee Horticultural Association. — At the recent 
monthly meeting of this Association, a paper on “ Hardy Azileas,” 
by Mr. Hugh Fraser, Leith Walk Nurseries, Edinburgh, was read, in 
the absence of the writer, by Mr. Hutton, the President. In intro¬ 
ducing the subject the writer said that the genus Azalea had a very 
wide geographical distribution, representatives being found in most 
quarters of the globe. One species had its home on Scottish mountains. 
Though lacking to some extent the imposing grandeur of the Rhodo¬ 
dendrons, Azaleas stood beyond question in the first rank among hardy 
flowering shrubs, commending themselves by their profuse blooming 
qualities and by the exquisite richness of their colours. 
- Coffee Estates in Angola. —We learn from the “ Kew 
Bulletin” that altogether the estates of Cazengo and Golungo Alto 
number somewhere between fifteen and twenty. The largest of them— 
one of eight, which are in the hands of the Banco Nacional Ultramarino 
of Portugal—was described to the writer by the courteous and hospitable 
manager-in-chief of the mortgaged group as “ six miles long and of 
breadth unknown,” the map of it which he was engaged upon being 
then incomplete. Its crop for 1893 was estimated at 214 tons, and for 
the first time in the history of the property systematic planting had 
been undertaken, which was expected to result in the addition of 
118,000 trees. One of the smallest of the holdings, which belongs to a 
British firm, is registered as covering 1424 acres, but only 464 contain 
Coffee. The bean of this indigenous Coffee is not only of poor flavour, 
but also of very small size, and on account of the height of the trees 
and their straggling character is often hardly worth the trouble of 
picking. An acre of Coffee, with the plants 6 feet apart and properly 
cultivated, is considered in other parts of the world good for a crop of 
half a ton. Under such conditions the 464 acres above referred to 
might be expected to bear at least 200 tons, whereas at present they 
only yield 35. There is no digging or manuring done on any of the 
properties. The trees are simply cleared of under-growth and pruned a 
little, in the roughest and readiest manner, and then left to do the best 
they can with such nutriment as rots on the surface around. But it is 
easier to indicate possibilities than to attain them ; the problem exists 
in the usual terms of labour and management, and for those who can 
solve it the reward is fortune. 
VAGARIES IN LABURNUMS. 
A FRIEND of mine has two Laburnum trees that present features 
which may, I think, be interesting to your readers, and upon the 
occurrence of which you will probably be able to throw some light. 
The trees were bought some few years ago in the belief that they were 
purple Laburnums, but neither of them has ever produced any purple 
flowers. Each has produced on some branches yellow flowers, on others 
pink flowers, and on others a mixture of sprays of yellow and sprays of 
pink flowers. On some of the branches bearing sprays of these two 
colours I have observed a feature even more remarkable, viz., a spray of 
yellow flowers growing on one side, and a spray of pink flowers growing 
on the opposite side at a distance of not more than 3 or 4 inches, the 
pink spray being again succeeded by a spray or sprays of yellow flowers. 
One of the trees has also thrown out here and there on some of its 
branches thick bunches of the purple Cytisus. This is a freak of Nature 
of which I have seen two or three instances in years past; but I have 
never seen yellow flowers and pink flowers upon the same Laburnum 
trees before, and I do not remember ever to have either read or heard of 
such an occurrence. I enclose herewith sprays of the Laburnum 
blossom, and also of the Cytisus blossom.— Rusticus. 
[We have seen several trees similar to yours, though they are not 
common in gardens. It is known as Cytisus Adami, and is a graft 
hybrid between C. Laburnum and C. purpureus, obtained by Mr. Jean 
Louis Adam in 1825 in establishing the purple species on the common 
Laburnum. In this process it is supposed that a cell of the one species 
became divided and united to a cell of the other, and the result has been 
a plant producing not only flowers of each species separately, but others 
partaking of the characters of both. There are other instances in the 
vegetable kingdom in which a similar union of cells is believed to have 
taken place, but Cytisus Adami is the best known and best established. 
We recently observed a tree of Cytisus Adami in Mr. Smee’s garden at 
Hackbridge, Surrey. It was also flowering in Mr. Van Geert’s collection 
a few weeks ago. In the same collection we observed that where the 
golden leaved Laburnum had been grafted on young stocks of the 
ordinary green leaved kind, and the scions “ took,” but were subsequently 
destroyed, that the growths from the stocks were not green but more or 
less yellow, some being quite as bright as if they were growths from the 
scions. There were dozens of examples of this. It is remarkable that 
grafting or budding with one variety will occasionally, as the tree grows, 
produce three or four forms differing in colour and the character of the 
leaves and racemes. We have not only seen purple and yellow flowers 
on the same tree but about half and half in the same raceme. There is 
no accounting for the vagaries of Laburnums when grafting has been 
resorted to. Your plants are named in another column.] 
