Definitions of weeds

Definitions from plant scientists

“A plant out of place or growing where it is not wanted” W.S. Blatchley 1912

“A plant that is growing where it is desired that something else shall grow” A.E. Georgia 1916

“The obnoxious plants are known as weeds” W.W. Robbins et al. 1942

“Those plants with harmful or objectionable habits or characteristics which grow where they are not wanted, usually in places where it is desired that something else should grow” W.C. Muenscher 1946

“Higher plants which are a nuisance” J.L. Harper 1960

“A plant growing where we do not want it” E.J. Salisbury 1961

“A plant growing where it is not desired; or a plant out of place” G.C. Klingman 1961Definitions by enthusiastic amateurs“A plant whose virtues have not yet been discovered” R.W. Emerson 1912

“Weeds have always been condemned without a fair trial” F.C. King 1951

Ecological definitions

“Weeds are pioneers of secondary succession, of which the weedy arable field is a special case” A.H. Bunting 1960

“A plant which contests with man for the possession of the soil” W.S. Blatchley 1912

“Opportunistic species that follow human disturbance of the habitat” T. Pritchard 1960

“The cosmopolitan character of many weeds is perhaps a tribute both to the ubiquity of man’s modification of environmental conditions and his efficiency as an agent of dispersal” E.J. Salisbury 1961

“A weed is defined as a plant which has, or has the potential to have, a detrimental effect on economic, social or conservation values.” (Definition adopted in Western Australia).