128 
JOURNAL OF HORTICULTURE AND COUAGE GARDENER. 
[ February 12,1355. 
summer, and get the wood well ripened, and at pruning time he should leave 
six to eight eyes of this rod, which will show fruit at every eye. The secret 
of getting this and other vigorous Vines to be fruitful is to have the wood 
well ripened. Here we prune this Vine on the old spur system, leaving 
from two to three eyes, and we get any amount of fruit. I have seen this 
Vine inarched on another and the young rod grown under the shade of 
other Vines. Next season it showed little or no fruit, and was then abused 
as a Vine that would not bear!—W m. Thomson, Tweed Vineyard. 
In reply to your correspondent “ Vectis ” I have to say that what I 
practise and have recommended in cropping this splendid Grape is either 
to leave three or four buds of each spur or to crop it on young rods. 
There is a house full of it here, and for many years I have adopted the 
last-named method. The bearing rods are 4 feet apart, and between each 
pair a young rod is produced. At pruning time the rod that bore fruit is 
cut down and sends up a growth for bearing next year, and so the system 
is carried on year after year. Abundance of fruit is produced under by no 
means favourable circumstances. The Vines were planted in 1869, and the 
roots are all in an outside border.—D. Thomson, Dnnnlanrig, 
ORCHIDS AT FERNFIELD, BRIDGE OFi ALLAN. 
I DO not remember seeing the Fernfield Orchids more attractive than 
they are now. Many beautiful sorts are flowering, with ample promise of 
others to follow, and the perfume is delightful, with, of course, vigorous 
health and growth everywhere. The skilful treatment of Mr. Kidd is 
seen at a glance. No wonder cases of “ Orchid fever ” in the district are 
reported. Any lover of flowers within reach of Dr. Paterson’s may have 
a treat by calling at Fernfield, Bridge of Allan.— Northern Amateur. 
There is now la fine display of Orchids in the Fernfield collection, as 
the following will, show : — 
Cattleja Triause, in abundance. 
C. Symei. 
C. labiata Percivaliana. 
C. cristata, several good specimens. 
Lajlia superbiens (large plants with four 
spikes). 
L. harpophylla. 
Cypripedium Haynaldianum. 
C. Sedeni. 
C. villosum. 
C. pardinum. 
C. Maulei. 
C. venustum. 
Cymbidium Lowii (six spikes). 
Oncidum serratum. 
0. lingna3forme. 
O. incurvum. 
Vanda Cathcarti. 
V. tricolor Patersoni. 
V. suavis. 
Dendrobium Wardianum. 
D. Ainsworthi. 
D. nobile. 
Sophronitis grandiflora. 
Leptotes bicolor. 
Zygopetalnm Mackayi. 
Z. intermedium. 
Phalivnopsis Scliilleriana. 
Odontoglossum Alexandra; (a great 
number). 
O. Pescatorei. 
O. Rossi majus. 
O. triumpkans. 
O. cordatum. 
0. praenitens. 
0. Uro-Skinneri. 
0. nebulosum. 
O. pulchellum. 
Lycaste Skinneri (a fine lot). 
L. Skinneri alba. 
Masdeyallia ignea. 
M. tovarensis. 
M. amabilis. 
Angrtecum sesquipedale. 
Pleione humilis. 
Pilumna fragrans. 
The Cattleyas and Odontoglossums are now flowering grandly and 
render the houses very attractive. The plants are all in the best health, 
and most creditable to the gardener, Mr. Kidd, who, I understand, is 
desirous of obtaining another situation farther south.— An Occasional 
Visitor. 
[We have received from Dr. Paterson a spike of three flowers of an 
early -flowering Cattleya Trianas, which is from a plant bearing three 
similar spikes. It is a lovely variety with blush sepals and petals, and an 
intensely rich crimson lip, also possessing a strong perfume.] 
. ROSE MILDEW—GYPSUM. 
Some correspondence having appeared in your columns with reference 
to the above, it would be well perhaps to consider mildew which affects 
other plants in order to experiment in the hope of destroying it in Roses. 
Hops are likewise subject to a “ mould ” or mildew, which Mr. C. White- 
head remarks in his treatise on “ Hops from the Set to the Skylight,” “is 
due to an insidious parasitic fungus, known as Spasrotheca Castagnei, of 
the group Erysiphe, allied to the fungus which causes the mildew in 
Vines.” Sulphur is applied to Hops in the form of flowers of sulphur by 
means of a machine called a sulphurator, which dusts it over the plants, 
apd it is generally considered to be a cure for the mildew, and a preven¬ 
tive if put on early. An agricultural chemist, in giving a lecture on the 
subject to a farmers’ club in this neighbourhood, gave it as his opinion 
that if sulphur was applied in an available form to the roots he believed 
that it would prevent mildew. A Hop grower afterwards stated that he 
had found this theory corroborated by practice, and that having applied 
sulphur in the form of gypsum to his Hops they were very free from 
mould, while his neighbour’s on the other side of the hedge were badly 
attacked. 
The above chemist stated that sulphur as applied by flowers of 
sulphur is not assimilable by the roots, while it is when supplied in 
gypsum. As an analogy the human frame needs phosphorus and potash, 
but they cannot be taken in the crude mineral form without doing as 
much harm as good, while if taken in an assimilable form in vegetables 
they are of great benefit. Hence those growers who have applied 
quantities of sulphur at a considerable expense to the leaves have only 
derived a temporary and incomplete benefit, and have not gone to the 
root of the matter ; while it seems that if the sulphur is applied so as to 
be taken into the substance of the plant, it will not be susceptible to the 
disease. Gypsum being composed of lime fifty-six parts, dry sulphuric 
acid eighty parts, and water thirty-six parts, is a good and cheap medium 
for applying sulphur and lime to the soil when required. 
As I have a quantity by me for use on my farm, I intend giving my 
Roses a dressing with it this winter in order to see if it has a beneficial 
effect. As some of your readers may like to try it too, and may not know 
where to get it, I may mention that I get mine from the Sub-Wealden 
Gypsum Co., Hawkhurst, Sussex. Sulphur can also be supplied as a 
manure in the form of sulphate of ammonia, superphosphate, and gas 
lime, but I should hesitate to use the latter unless put in the ground some 
time before the Roses were planted in case it killed them; and for my 
own part I prefer to use gypsum and bone meal rather than super¬ 
phosphate.— Walter Kruse, Maidstone, 
The reason I have not replied earlier to Mr. Clayton's letter on this 
subject (page 49) is not because I believe it to be exhausted, nor because 
it is uninteresting and unimportant, and not because I think he is any 
nearer to “ the root ” of the question than when he first raised an 
objection to my brief reply to “ H.’s” inquiry, but simply because I hoped 
others, both practical and philosophical, would give us the benefit of 
their experience and knowledge respecting this insidious and in some 
respects mysterious and troublesome foe. I should not like to appear 
discourteous to Mr. Clayton by not replying to his very practical and, 
in some respects, suggestive and excellent letter, nor should I wish him 
to imagine by my silence that I was convinced by the arguments he has 
adduced, nor that his direct contradiction of my statement that “ mildew 
is more prevalent in cold wet summers” has confounded me. It is some 
satisfaction to me to learn that it is on his own responsibility he does so. 
As to his claim of support in this view from so eminent a fungologist as 
Mr. Worthington Smith, I venture to think if, as Mr. Clayton suggests, 
I have not, compared with himself, “ read Mr. Smith’s article so care¬ 
fully,” I have at least succeeded in interpreting that gentleman’s meaning 
more correctly. 
When Mr. Smith says “ the spores of Rose mildew very soon perish in 
the air, they cannot withstand dryness, heat, moisture, or cold,” I fail to 
see why Mr. Clayton should, even for argument’s sake, so resolutely seize 
hold of the two last and least destructive agents of mildew—moisture and 
cold, and altogether taboo the two former and most potent ones—dryness 
and heat, and conclude forthwith that therefore “ cold wet summers are 
not the more favourable to its growth.” This line of argument is scarcely 
fair to the author of that quotation, nor likely to convince his readers ; 
because if the whole of the quotation was used in the same sense it would 
imply that as dryness, heat, moisture, and cold are destructive agents, 
these being the chief elements of the atmosphere, mildew could, not 
therefore exist. If I correctly read Mr. Smith he here merely wished 
particularly to show that while floating in the air the spores are easily 
and quickly destroyed by either of these agents. He does say “there is 
no evidence to show that they can live more than a day or two at most.” 
By this I infer he means the unattached spores, because he again says, 
“ unless they light upon Roses or some allied plants they perish at once,” 
and “ that Nature has provided for this emergency by the constant and 
repeated production of vast numbers of fresh spores.” 
I beg Mr. Clayton to observe that I simply said “ cold wet summers.” 
What particular degrees of heat will cause the spores to vegetate, and on 
the other hand destroy them, I know not; but this I have frequently 
observed, that two or three days after a hailstorm in summer, or when a 
sudden depression of temperature has occurred, mildew is always more 
prevalent on Roses, and in low-lying sheltered damp positions they are 
much more liable to its attacks than in elevated and drier ones. His 
statistics of the weather do not strengthen his argument, and most 
certainly they do not refute what I have stated. I admit that the mean 
temperature of August last year was somewhat higher than that of July, 
also that the rainfall was less ; but he again omits a very powerful factor 
in climatic conditions, one which is perhaps the most active and important 
in respect to the influence it exercises on the spores of mildew—viz., the 
humidity of the atmosphere, if he will again kindly refer to your 
meteorological records he will find that duriog the latter part of August 
and throughout September, the period in which he states mildew was 
“rampant,” that the dew point was considerably lower than it was in 
July and the early part of August. 
The mean atmospheric humidity during the three months was as 
follows :—July 74 per cent., August 68 per cent., September 81 percent.; 
but if the six weeks ending September 30th be taken—that is the period 
when your correspondent says mildew was most rampant, the mean per¬ 
centage of moisture was 78 per cent., while the rainfall during that period 
was 3 inches, and the mean temperature was reduced to 59°. But for our 
present purpose general statistics of the weather are perhaps more 
misleading than otherwise, because the climatic conditions which engender 
and encourage mildew are often very limited as regards space and of 
short duration; if, however, they are carefully considered locally they 
tend to throw a great deal of light on the growth and spread of this 
otherwise obscure disease. There is one point on which I quite agree 
with him when he says “ it is always worst when hot sunny days are 
followed by heavy dews at night.” This means that in the months of 
August and September Roses planted in low situations are frequently 
bathed for sixteen out of the twenty-four hours in an atmosphere saturated 
with moisture when the temperature of the dew point is often reduced 
nearly to freezing. These are the very conditions of the atmosphere 
which are most favourable to its increase, and such weather nearly always 
occurs in fine autumns after cold wet summers. If we could command 
these hot days without the excessively damp cold nights I do not think 
