Historically, pasture breeders have not considered environmental weed risk in species selection and assessment. Consequently several pasture or former pasture species are now problematic environmental weeds in Australia. The CRC for Plant-Based Management of Dryland Salinity (CRC) has taken a pro-active approach to prevent further introduction or promotion of weedy pasture species by developing...

Weed pressure in 1995 was incredible! What happened to produce such a glorious crop of weeds? The answer: drought! The Drought of 1995 and Weeds and Weed Control in 1996 Weed pressure in 1995 was, in a word, incredible! I toured many areas — golf courses, lawns, athletic fields, and institutional grounds — that were solid crabgrass, knotweed, clover, etc. In many of these areas, if there weren’...

Weed control is generally the first major decision to be made once alfalfa has germinated. Managing weeds in a timely manner is necessary to provide maximum production of high quality alfalfa hay. A poor weed management decision can lead to stand loss, poor quality hay, unacceptable weed control, alfalfa injury and a loss of money. Herbicides are applied to 75% of newly planted alfalfa in Calif...

The term weed is referring to plants used as culinary herbs and medicinal plants as well as ecologically adaptive and invasive segetal plants. In Europe, pollen of ragweed, mugwort, English plantain and pellitory are the main elicitors of weed pollen allergies. Presently, 35 weed pollen allergens have been identified. The most relevant belong to the protein families of pectate lyases, defensin-...

Chemical control ofweeds has increased agricultural productivity, but complete reliance on chemicals has serious drawbacks. These include high cost per acre, decreasing effectiveness, negative effects on plant community diversity, and increased opportunities for environmental contamination. One alternative is biocontrol, the use ofbiologicalfactors that naturally limit weed populations. Long-te...

This paper describes the modeling of a weed infestation risk inference system that implements a collaborative inference scheme based on rules extracted from two Bayesian network classifiers. The first Bayesian classifier infers a categorical variable value for the weed–crop competitiveness using as input categorical variables for the total density of weeds and corresponding proportions of narro...

A functional approach to predicting shifts in weed floras in response to management or environmental change requires the combination of data on weed traits with analytical frameworks that capture the filtering effect of selection pressures on traits. A weed traits database (WTDB) was designed, populated and analysed, initially using data for 19 common European weeds, to begin to consolidate tra...

Crop rows oriented at a right angle to sunlight direction (i.e., east–west within the winter cropping system in Western Australia) may suppress weed growth through greater shading of weeds in the interrow spaces. This was investigated in the districts of Merredin and Beverley, Western Australian (latitudes of 31u and 32uS) from 2002 to 2005 (four trials). Winter grain crops (wheat, barley, cano...

eld to prepare for planting, while the tractor and crew on the right are planting trees. This method provides a weed-free soil immediately after planting for preemergence herbicide applications. W eeds reduce the value of nursery crops. They compete with crops for nutrients, light, and water. Some vine weeds climb nursery crops, requiring excessive labor for hand removal. Most serious are peren...

The use of glyphosate, as a post-emergence broad-spectrum herbicide in genetically modified glyphosate-tolerant (GT) cotton, supposes a big change in weed management programs with respect to a conventional regime. Thus, alterations in arable flora and arthropod fauna must be considered when evaluating their potential impacts. A 3-year farm-scale study was conducted in a 2-ha GT cotton crop, in ...