For piercing-mouthed pests like Aphides no wash is of use unless it contains a basis of soft soap. This softsoap wash kills by contact, and may be prepared in the following way: - Dissolve 6 to 8 lb of the best soft soap in boiling soft water and while still hot (but of course taken off the fire) add 1 gallon of questions involved, under their own headings.
In the not too distant future, tiny robots will detect pests on produce and emit a signal to shoo them away.
One of the worst pests of pear trees is the pear midge, known as Diplosis pyrivora or Cecidomyia nigra, the females of which lay their eggs in the flowerbuds before they open.
Cereal pests can only be treated by general cleanliness and good farming, and of course they are largely kept down by the rotation of crops.
In 1883 appeared a work on fruit pests by William Saunders, which mainly applies to the American continent; and another small book on the same subject was published in 1898 by Miss Ormerod, dealing with the British pests.
Among the Coleoptera or bettles there is a group of world-wide pests, the Elateridae or click beetles, the adults of the various " wireworms."
With such subterranean pests little can be done beyond rolling the land to keep it firm, and thus preventing them from moving rapidly from plant to plant.
The mole cricket (Gryllotalpa vulgaris) and various cockroaches (Blattidae) are also amongst the pests found in this order.
One of the most p im ortant ways of keeping insect pests in check is by " spraying " or " washing."
- Among the most Interesting modern means of waging war against epidemic pests is that of introducing other epidemics among the pests themselvese.g.
Statistics.See Wyatt, Agricultural Ledger (Calcutta, 1895), p. 71; Balfour, The Agricuttural Pests of India (1887), p. 13; Eriksson and Henning, Die Getreideroste; the publications of the U.S. Agricultural Department; the Kew Bulletin; Zeitschrift fr Pjlanzeiikrankheiten, and elsewhere.
One noteworthy feature in Liberia, however, is the relative absence of mosquitoes, and the white ants and some other insect pests are not so troublesome here as in other parts of West Africa.
That Diptera of the type of the common house-fly are often in large measure responsible for the spread of such diseases as cholera and enteric fever is undeniable, and as regards blood-sucking forms, in addition to those to which reference has already been made, it is sufficient to mention the vast army of pests constituted by the midges, sand-flies, horseflies, &c., from the attacks of which domestic animals suffer equally with man, in addition to being frequently infested with the larvae of the bot and warble flies (Gastrophilus, Oestrus and Hypoderma).
Most, if not all, of the important knowledge of remedies comes from America, where this subject reaches the highest perfection; even the life-histories of some of the British pests have been traced out in the United States and British colonies more completely than at home, from the creatures that have been introduced from Europe.
The most important works dealing with fruit and other pests come from the pens of Saunders, Lintner, Riley, Slingerland and others in America and Canada, from Taschenberg, Lampa, Reuter and Kollar in Europe, and from French, Froggatt and Tryon in Australia.
The most important Hymenopterous pests are the sawflies or Tenthredinidae, which in their larval stage attack almost all vegetation.
The pupae in most of these pests are found in an earthen cocoon beneath the ground, or in some cases above ground (Lophyrus pini).
The best-known dipterous pests are the Hessian fly (Cecidosnyia destructor), the pear midge (Diplosis pyrivora), the fruit flies (Tephritis Tyroni of Queensland and Halterophora capitata or the Mediterranean fruit fly), the onion fly (Phorbia cepetorum), and numerous corn pests, such as the gout fly (Chloropstaeniopus) and the frit fly (Oscinis frit).
The dipterous garden pests, such as the onion fly, carrot fly and celery fly, can best be kept in check by the use of paraffin emulsions and the treatment of the soil with gas-lime after the crop is lifted.
To check them, " grease-banding " round the trees has been adopted; but as many other pests eat the leafage, it is best to kill all at once by spraying with arsenical poisons.
Sugar-canes suffer from the sugar cane borer (Diatioca sacchari) in the West Indies; tobacco from the larvae of hawk moths (Sphingidae) in America; corn and grass from various Lepidopterous pests all over the world.
Pests and Diseases of the Cotton Plant.
- It is common knowledge that when any plant is cultivated on a large scale various diseases and pests frequently appear.
The following notes deal only with the practical side of the question, and as the United States produce some seven-tenths of the world's cotton crop attention is especially directed to the principal cotton pests of that country.
The boll worm is most destructive in the south-western states, where the damage done is said to vary from 2 to 60% of the crop. Taking a low average of 4%, the annual loss due to the pest is estimated at about 1 - 2,500,000, and it occupies second place amongst the serious cotton pests of the U.S.A. The boll worm is widely spread through the tropical and temperate zones.
Locusts, green-fly, leaf-bugs, blister mites, and various other pests also damage cotton, in a similar way to that in which they injure other crops.
Inspection of a field of cotton shows that different plants vary as regards productiveness, length, and character of the lint, period of ripening, power of resistance to various pests and of withstanding drought.
The improvements desired in cotton vary to some degree in different countries, according to the present character of the plants, climatic conditions, the chief pests, special market requirements, and other circumstances.
In New Zealand and Australia rabbits, introduced either for profit or sport, have increased to such an extent as to form one of the most serious pests that the farmers have to contend against, as the climate and soil suit them perfectly and their natural enemies are too few and too lowly organized to keep them within reasonable bounds.
So far the Hevea plantations in Ceylon and the East have not been seriously troubled by insect or fungoid pests, and those which have occurred have succumbed to proper treatment.
This is partly due to such pests as the vampire bat and bush ticks (carrapatos), and partly to the unprogressiveness of the cattlemen.
It also conducts campaigns against locusts and other pests and helps irrigation settlements.
When the vines are in flower, and when the fruit is colouring, the evaporating troughs should be kept dry, but the aridity must not be excessive, lest the red spider and other pests should attack the leaves.
To destroy the seeds, &c., of weeds, and the larvae of insect pests, a fire is often lighted, kept from the ground itself by intervening wood logs, or the seed-bed is thoroughly steamed.
Tobacco, like other cultivated plants, is subject to attack by various pests and diseases, but fortunately these are less destructive than with many crops.
Some of the best oranges in the world are grown, and exported; but sufficient care is not taken to keep down insect pests, and to replace old trees.
Many scale-insects are among the most serious of pests, but various species have been utilized by man for the production of wax (lac) and red dye (cochineal).
Strenuous devotion to the deliverance of mankind from dangers and pests is the " virtue " which, in Prodicus' famous apologue on the Choice of Hercules, the hero preferred to an easy and happy life.
Barley is liable to smut and the other fungus diseases which attack wheat, and the insect pests which prey on the two plants are also similar.
The pleasant climate has certain drawbacks; the coastal farmer finds that blights and insect pests thrive in the comparative absence of hard frosts.
Among imported pests the rabbit and sparrow, and a numerous company of European and American thistles and other weeds, have to be systematically contended with.
These pests can be kept in check by syringing with nicotine, soft-soap and quassia solutions, or by "vaporising" two or three evenings in succession, afterwards syringing the plants with clear tepid water.
In pleasing contrast to such pests are the butterflies of all sizes and colours, beetles of an inconceivable variety of size, shape and colouration, and ants of widely dissimilar appearance and habits.
The cultivation of osiers is attended with many disturbing causes - winter floods, spring frosts, ground vermin and insect pests of various kinds, sometimes working great havoc to the crop.
Insects are numerous, and of about 500 species of beetle some 80% are not known to exist elsewhere; cockroaches and green locusts are pests, as are, also, mosquitoes,' wasps, scorpions, centipedes and white ants, which have all been introduced from elsewhere.
C. Cooke, Fungoid Pests of Cultivated Plants; Thos.
Luther was never a "wandering student"; his parents were too careful of their child to permit him to lead the life of wandering licence which marked these pests of medieval German scholastic life.
Mosquitoes and sand-flies are the chief insect pests, and in some districts are very troublesome.
Apart from some fulminations against such modern pests s socialism, communism, secret societies, Bible societies, clerico-liberal societies," the Syllabus says nothing that the papacy had not been saying for hundreds of years.
Under certain circumstances, however, the native animals may recover, for in some cases they even profit by man's advent, and at times themselves become pests, like the Kea parrot (Nestor notabilis), which attacks sheep in New Zealand, and the bobolink or rice-bird (Dolichonyx oryzivorus) in North America.
Both these pests have been successfully combated, largely by the use of sulphur and by grafting immune American vines upon native stocks.
They are also fond of grapes and other fruits, and are thus the pests of the vineyard as well as the poultryyard.
The chief pests are mosquitoes, termites and the serut, a brown fly about the size of a wasp, with a sharp stab, which chiefly attacks cattle.
Wouldn't that be something: Plants that would convert nitrogen from the atmosphere directly into ammonia they could use or plants that gave off the odor of other plants that pests avoid?
Of animal pests the ox warbles (Hypoderma lineata and H.