Life Sciences Commons^™

Weeds Can Poison Crops, Aik Hock Cheam

Journal of the Department of Agriculture, Western Australia, Series 4

Weeds can interfere with the growth of a crop simply by competing with the crop for nutrients, moisture and light. But some weeds also release chemicals that inhibit the germination and growth of crop plants; the technical term for this is allelopathy. Aik Cheam outlines the problems caused by two common weeds and the discusses preventative measures.

Research On Declared Plants And Other Weeds, G. A. Pearce

Journal of the Department of Agriculture, Western Australia, Series 4

Knowledge about weeds is necessary to assess their significance, devise control measures and to select those which are to be declared for the purposes of the Agricultural and Related Resources Protection Act.

Once a plant has been declared in Western Australia, all landowners must control and prevent its spread to new areas and work towards eradicating known infestations. The Act also declares plants which are prohibited from entering the State.

It is becoming more and more important to provide specific reasons for the declaration of a weed and its placement in a certain category. Such decisions require appropriate action to …

Faster Weed Germination With Early Cultivation, Geoffrey A. Pearce

Journal of the Department of Agriculture, Western Australia, Series 4

The key to cultural control of weeds in cereal crops is an understanding of the factors which govern germination of the weed seeds.

Covering the seed with soil keeps out light, provides a stable moisture supply and makes germination faster than if the seed is left on the soil surface.

Shallow cultivation at the start of the growing season provides the soil cover needed for fast, even germination of weed seeds.

Annual Pasture And Weed Plant Ecology, B J. Quinlivan

Journal of the Department of Agriculture, Western Australia, Series 4

The purpose of this article is to outline a few basic principles of pasture and weed ecology with particular reference to seed dormancy mechanisms.

These principles apply to many pasture plants and weeds, although their relative importance varies with the particular plants under study.

Calotropis Or Rubber Tree (Calctropis Procera (Linn.) Dryand), G R W Meadly

Journal of the Department of Agriculture, Western Australia, Series 4

TWO SPECIES of Calotropis have been introduced to the northern parts of Western Australia. They are closely related in most respects but differ in one fundamental feature which decides their significance as undesirable plants.

Cotton Bush (Asclepias Fruticosa L.) : Garden Plant Now A Noxious Weed, G R W Meadly

Journal of the Department of Agriculture, Western Australia, Series 4

THE cotton bush is native to South Africa but is now naturalised in most tropical and sub-tropical countries of the world. Its spread is, in no small measure, due to being grown frequently as a garden subject.

The Control Of Doublegee, Geoffrey A. Pearce

Journal of the Department of Agriculture, Western Australia, Series 4

FOUR years ago no practical recommendations could be made for the control of doublegee.

With money provided by the State Wheat Research Fund, research has been undertaken into the control of this weed, and there is now no reason why most farmers cannot bring doublegee under control.

Weeds In Lawns. 1. Identification Of Weeds In Lawns, Robert Dunlop Royce

Journal of the Department of Agriculture, Western Australia, Series 4

ACCURATE identification of weeds is the first principal of weed control with modern chemicals.

This is as true for weeds in lawns as any other weeds.

Special Seeds Help Weeds To Spread, Robert Dunlop Royce

Journal of the Department of Agriculture, Western Australia, Series 4

PERHAPS the most important characteristic of a plant which establishes it as a weed is that it serves no useful purpose under the circumstances in which it occurs.

Cotton Fireweed : A Native Weed Menace, G R W Meadly

Journal of the Department of Agriculture, Western Australia, Series 4

INTRODUCED plants have provided most of our weed problems. Cape tulip, double gee and soursob come from South Africa, Saffron thistle, Paterson's curse, wild turnip and wild radish from Europe, mesquite from the southern United States and Bathurst burr from South America.

The relatively few native plants which have become troublesome weeds include Afghan thistle and Sarsaparilla.

Factors In Weed Propagation, G R W Meadly

Journal of the Department of Agriculture, Western Australia, Series 4

I N crop and pasture plants, seed production and harvesting are of vital impartance.

In a negative way, the formation of seeds by weeds can be equally important.

Afghan Thistle (Solanum Hystrix R. Br.), G R W Meadly

Journal of the Department of Agriculture, Western Australia, Series 4

DURING the summer months it is usual to receive many specimens of a prickly plant with blue flowers similar to those of a potato. It is commonly known as Afghan Thistle or Prickly Potato Weed.

This plant is not a thistle, although it has the prickly foliage characteristic of many members of that group. The botanical name is Solanum hystrix which places it in the same family as the tomato, potato and tobacco.

Relatives also include weeds such as the thornapples, black nightshade and apple of Sodom.

The name Prickly Potato Weed, although somewhat unwieldy is therefore more appropriate than …