News & Updates:

Karathane has not been used extensively in Australia, yet. Oversea reports are enthusiastic over it as both a fungicide for killing established mildew and a miticide. Arathane, Mildex, and Iscothan are alternative trade names. Its full chemical name is dinitrocapryl phenyl crotonate.

From the point of view of control, insects may be divided into two groups-leaf-eaters and sap-suckers. Many leaf-eating insects do no harm in the insect stage of their life cycle-that is, while they are moths or butterflies. During that phase they mate and deposit eggs, but neither eat nor drink. The damage is done by their caterpillars, which are best killed by stomach poison, the chief of which are E605, Systox, arsenates of lead and calcium, metaldehyde, and rotenone.

Arsenic is the most potent stomach poison for garden uses. Bought as arsenate of lead paste, it is used for killing caterpillars, being sprayed on plants in the strength of one ounce of paste to each gallon of water. Cutworms are large and need to eat a lot of a plant before getting a fatal dose of arsenic. For them, it is better to lay baits made up of one pound of bran, one ounce of calcium arsenate, a pinch of salt, and enough water to make it damp; it must be thoroughly mixed. Small baits should be placed near each rose plant, preferably after sunset to avoid poisoning birds, and to save the baits from drying before the cutworms reach them. Dry baits should be removed promptly, for they are useless, besides killing birds. Arsenates are compatible only with nicotine sulphate. Mixed with soaps, they interact to form soluble compounds of sodium and arsenic. These are very powerful poisons to plants of all kinds, and are the bases of many weed-killers.

Metaldehyde is less poisonous than arsenic and does not attract birds readily. It is effective in controlling slugs and snails, which can cause damage to rose blooms.

Rotenone is the active constituent of all Derris dust preparations. These are non-poisonous to mammals and so are safe on edible plants for human or animal consumption, but they are not nearly as lethal to pests as arsenic, and we do not need to consider the aspect of animal foods in our flower gardens.

Stomach poisons on the surface of the foliage are, obviously, useless against sap-sucking insects. They can be attacked by contact sprays, or by rendering the sap poisonous to them. Contact sprays act in widely differing ways. Those that are absorbed by plants, either through the leaves or the roots, and act as stomach poisons to sap-suckers, are known as systemic poisons; a great deal of research is being done in endeavour to develop more of them.