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I GARDENING NOTES. I I If any reader, who is in a (lifficulty with reference to his garden, will write directly to the address given beneath, his questions will all be answered in full detail, free of charge and by return of post.—(Ed.) FuNGI AND FUNGICIDES.—Amongst the many enemies which beset cultivated plants, none are of greater moment than those belonging to the vege- table kingdom—the parasitic fungi, which develop upon growing crops, and produce maladies known as iungous diseases. As an instance of the enormous damage done by these pests, we may mention that so far back as 1886 the Commissioner of the U.S.A. Department of Agriculture estimated the injury done to Indian corn and wheat by fungi in America during a single year at over two hundred million dolars. Fruits, however, suffer much more severely than cereals as a rule, and it would be difficult to find a single vegetable or field crop which has not some fungous enemies. Unfor- tunately, the space at our disposal does not permit of our tracing out a specimen life history of one of these fungi, but a few wurds must be devoted to the methods by which they are distributed. The princi- pal means is by the transportation of summer spores, or, as it were, seeds, which are produced in countless numbers, and which are wafted here and there by every breath of wind, are washed from leaf to leaf and from leaf to root by rains, and soon germinate in their new situa- tions, so that infection may be spread with marvellous rapidity. They are also, doubtless, carried from place to place by adhering to the feet of insects and birds. Other kinds of spores are distributed by other agencies. Thus, for instance, the smut diseases of corn are frequently spread in farm-yard manure, and in some cases the healthy kernels appear to become infected by contact with affected specimens during threshing, illustrating the ease which a malady may be extended by the use of farm implements. Then, too, in such deceases as the rot of potatoes, the mycellium of the fungus is present in the seed tubers themselves, and is consequently ready to infect the new crop so soon as it gets well started. Turning to out more immediate subject, we find that there are many ways in which the injuries of noxious fungi can be prevented. Perhaps the most important of these is a natural deduction from the observation that those plants which are weakened in vitality are more subject to attack than are vigorously growing specimens and it consists of employing those methods of cultivation and fertilization which tend most to the production of rapid development and early production. It is difficult to over estimate the importance of rotation of crops, because the spores of -the great majority of parisitic fungi pass the winter in the soil where the crop was grown; and if a plant of the same family be grown there the next season, it is almost certain to be attacked. As a general rule fungus and insect diseases causes injury to closely related plants, such as turnips and cabbages, so that the rotation must be arranged with the view of growing successively crops which are not liable to the diseases of their immediate predecessors, Many injurious fungi may be exten- sively destroyed by clean culture, and by keep- ing the garden free from weeds and rubbish of every kind. The burning of old potatoe tops' tomato plants, &c., destroys incalculable nUal" bers of spores, and some of the fungi investing cultivated crops also subsists upon weeds, so that the thorough cleaning of the ground may have most beneficial effects. Mechanical exclusion is sometimes employed for prevention, the most' familiar example being found in the practice of tying small paper sacks over bunches of grapes as soon as the fruit is formed, and allowing them to remain until it is ripe. These bags exclude insects and fungus spores. Where diseases shoW specific symptoms in the leaves, much may be done by stripping off and care- fully burning every affected part. We have seen serious infestations controlled in this way. The most practicable way of preventing the great majority of fungus maladies of cultivated plants is by the use of reliable fungicides, which may act .J in two ways, either by directly destroying any spores pfesent in the surface to which they ai'0 applied, or by remaining on that surface in ø. condition to destroy spores that may alight upou the plant hereafter. Very many fungus-killing substances have been proved of practical valuer and the list will probably be greatly extended during the next few years, as experiments are constantly progressing. Perhaps the most valn able and generally known of these is the combina- tion of copper salts, known as the Bordeaux mixture, prepared as follows :-Diswlve 6lbs. of copper sulphate in a wooden or earthenware vessel that will hold 45 gallons, using eight or ten gallons of water, as may be necessary. In a tub slake 41bs. of fresh lime, and when cola- pletely slaked, add sufficient water to make creamy whitewash. Pour this slowly through » coarse sack into the sulphate barrel; fill up with water, stir thoroughly, and the mixture' tlieti i-e?tdy fci- use. 14- then ready for use. It must be well stirred during application, a paddle being the best instrument for the purpose. The addition of just enoug h soap to make slight suds is advantageous, as 1t causes the mixture to spread more evenly ovet the plants. Eau Celeste is the next most impor- tant of fungicides, being prepared by dissolving 21bs. of copper sulphate in six or eight gallollo of water in an earthen or wooden vessel. ft. quart of ammonia is added, and the whole is mixed with some fifty or sixty gallons of water. Carbonate of copper, is commonly used in solu- tion, made by dissolving four ounces in twO quarts of ammonia, the whole being then added to a barrel of water. Flour of sulphur forms 0. valuable fungicide against mildews and other diseases. The powder may be applied directly to the moistened surface of the plants, or used a5 a wash, or in rumes, but in the case last. mentioned it is most important to see that the sulphur doe;J not actually take fire. Dry powders are most I conveniently applied to plants by means of powder distributor or no wrier helln«,< ,1 anlit- I -111, tions can be best and most evenly distributed by some kind of spraying pump, by which they may be finely divided. For garden use the knapsack sprayers are most desirable, as they can be worked I by one man, and arc powerful enough to spray ta standard trees, while competition has brought them within the rea,ch of everyone. IE. KEMP TOOGOOD, F.R.H.S., pro. Toogood & Sons. The Royal Seed Establishmerit, I Southampton.