Science and Practice in Farm Cultivation

by James Buckman

Plot 2. A small quantity of the seed germinated; the few resulting ears were free from blight.

Plot 3. Germinated, with a good and clean resulting crop.

Plot 4. The same result as Plot 3.

These experiments seemed to show that the pickling of wheat destroys the seed, so as to prevent germination when the seed is diseased or ill-formed; but if perfect seed be always employed, no pickling at all is necessary, it being strictly true that a diseased progeny must result from an imperfect stock in plants no less than in animals.

We have said that bunt is not peculiar to any climate; we have, however, always observed that employing seed from a warm district on a cold one, or using the finer white wheats in cold, exposed, or ill-drained situations, is sure to produce a large quantity of this fungus. Autumn-sown wheat, too, is less liable to the infection than spring wheat, which we attribute to the fact that many of the weaker plants will succumb to the cold rain and frost.

3. Uredo rubigo (Red-rust, Red-rag, Red-robin) makes its appearance in the inside of the chaff-scales, and ultimately in the green epidermis of the growing grains of wheat. Its first appearance is that of oval pustules, caused by the raising of the skin, which, ultimately bursting, shows the orange-coloured spores of the epiphyte. This must not be confounded with Cecidomyia tritici (wheat-midge), the larvæ of which are of a bright orange-colour; in the latter, the living moving worms may be easily detected by any common pocket lens or magnifying glass. Both these pests, to which we would apply the distinctive terms of Uredo rubigo (red-rust) and Cecidomyia tritici (red-gum), are exceedingly common in some seasons, and not unfrequently in the same crop. Good deep cultivation is the best remedy for the rust; but the treatment of the fly is a different matter. We would suggest the burning of smother-heaps on calm days, just as the wheat is bursting into ear, as smoke is decidedly obnoxious to these small insects, which in some seasons may be seen in thousands about the bursting wheat.

4 and 5. Uredo linearis; Puccinia graminis (Straw-rust and Mildew).—We refer to these epiphytes under one heading, as there can be but little doubt that the latter is a more advanced state of the former. They both occur in oblong patches on the leaves and straw of wheats and other grasses: in the uredo stage, of a dull red colour; in the puccinia stage, of a blackish hue. They are both, as, indeed, are all these fungi, interesting microscopic objects; but our object now is to describe them popularly. Both will always be found in abundance in cold poor soils, and more especially if the finer wheats be grown in such situations. The application of a dressing of salt to the soil is said to be a preventive. Be this as it may, the disease is said to be rarer in Cheshire, where salt is so much used by the farmer, than in any other county, in as far as we have observed.

Here, again, we incline to think that these are morbid affections of the plant. They are, indeed, viewed as such by Unger, in his “Die Exantheme Pflanzen,” in which the very title classes them with eruptive diseases of animals. Berkeley and Henslow, the two great authorities, however, do not accord with this view: the former remarks in reference to it—“Surely these plants are too distinctly, too regularly, and too beautifully organized to be the products of disease like warts or purulent matter in animals.” As, however, the microscope demonstrates that warts and eruptive diseases have also their special and curiously formed organisms, such a mode of reasoning is not conclusive.

Weeds have a great influence in producing mildew, which perhaps may be accounted for from the fact that weeds are in active growth as the wheat-stalks decline in vigour; and hence the constant evaporation of moisture from the weeds to the wheat is continually re-moistening an ever-drying surface—a most fertile source of mildew and moulds of several descriptions.

6. Puccinia fabæ (Bean-rust).[18]—The brown pustular rust-looking spots on the foliage of beans, and, indeed, occasionally on the stems and pods of beans, are sometimes common to this crop. They are usually accompanied by a lessening both in quantity and quality of this pulse, both in the garden and in field culture, but certainly more generally in the latter. Too gross manuring without well mixing the dung with the soil would seem to be a constant source of the evil. In fact, highly nitrogenized manures appear to favour the development of all this class of epiphytes, just as too much meat might bring about different forms of rash or eruptions in the animal. Weeds, which are too much permitted in beans, here aid in perfecting the mischief; hence, then, we may perhaps take it for granted that the mention of the causes of mischief suggests the remedy.