Amenity herbicide use increases

The marketing consultancy Produce Studies has carried out a survey of non-agricultural pesticide use during 1995 in England and Wales for the Department of the Environment (DoE). The main findings are set out below.

The survey was designed to assess the quantity of pesticides use, analyse the category of user, and determine the locations of use. These results, where possible, were compared with the last major study of this type which covered the year 1989.
    Since 1989 there has been an overall increase in the weight of herbicide active ingredient used from 550 tonnes to 623 tonnes, which represents an increase of 13% in six years.
    Herbicides accounted for 92% of the weight of all pesticides applied in the amenity market. Fungicides, insecticides and growth regulators accounted for the remaining 8% of usage. In 1995 the top six active ingredients were glyphosate, diuron, 2,4-D, dichlorophen, dichlobenil and ferrous sulphate. This represents a change from 1989 when the top six active ingredients were atrazine, simazine, diuron, 2,4-D, mecoprop and amitrole.

Decline in triazine use confirmed
Triazine herbicides are no longer present in the market in any significant volume, largely having been replaced by glyphosate and diuron. The triazines atrazine and simazine were banned for non-agricultural use in 1993 because residues were appearing too frequently in drinking water supplies. Since 1989 there has been an increased polarisation in the amenity herbicide market. The top two herbicides accounted for 69% of herbicide use, whereas six ingredients account for this level in 1989.
    The ban on the triazine herbicides has probably resulted in an increase in the number of herbicide applications and an increase in the overall volume used. This is because glyphosate is a non-residual herbicide and generally requires repeat applications in order to have the same control as the more persistent triazines.
    Hard surfaces and gravel areas account for 45% of pesticides applications which can allow pesticides to run-off quickly into water courses. The remaining 55% of applications were made to grassland or other vegetation surfaces.
    Amenity pesticide use is highest in densely populated areas where there is a higher road network demand, large leisure areas, typically more municipal buildings and support areas, and employment.
    An average 9.6% of work time was spent by those individuals dealing with weed/pest/disease control. The relatively low proportion of time emphasises the low priority some users place on these aspects and suggests that the decision maker may have difficulty gaining sufficient knowledge to reflect changes in environmental thinking.
    Costs, excluding machinery for weed/pest/disease control involve 55% labour costs and 45% chemical costs.

Methods of control
Chemical applications are the most frequently used weed control method. Alternative, more labour intensive methods, although used by a large number of organisations, represent only a small proportion of expenditure, thus implying a relatively small area was actually treated by these methods.

Weed control: Respondents were asked what weed control methods they used from a selection list. Nearly all (99%) used herbicides, 68% used mowing as a method of control, 61% used hoeing and 55% used hand or mechanical sweeping. Additional responses were mulching, hand weeding and hand digging.

Disease control: Just over a third (35%) used only chemical control against diseases. Non-chemical control methods used included cultural methods (34%), good management (17%), soil aeration (14%), correct fertiliser application (9%), drainage (9%), and iron sulphate (7%). (It is interesting to note that iron sulphate was not classified by many as a 'chemical'.)

Insect and pest control: About half (48%) used chemicals only to control insects and other pests. Non-chemical methods used included cultural control (15%), trapping (11%), biological control (10%), good husbandry (7%), and maintaining soil acidity (6%).

Conclusion
Major legislation changes, most notably the banning of triazine herbicides in 1993, implemented since the last study, have significantly altered the pesticide market. Initiatives by both the water industry and the DoE were also undertaken during the period 1991 to 1995 in an attempt to ensure the 'safe' use of pesticides, as well as providing some guidance to the user on alternative methods of control.
    However, the surveyors Produce Studies say it was evident that the private sector was the least aware of pesticide use issues. Low numbers of qualified decision makers in this sector highlighted the need for DoE and other government departments to target this sector of users. Low understanding of issues plus a low pesticide knowledge base must increase the risks of applications, the report concludes. (DB)
 

The Non-agricultural use of pesticides in England and Wales, Produce Studies, November 1996, 96pp. (Copies of the report are available from Andy Croxford, Chemicals and Biotechnology Division, DoE, Room A337, Romney House, 43 Marsham Street, London SW1P 3PY.)

[This article first appeared in Pesticides News No. 35, March 1997, page 14]