Pesticide usage in Scotland: arable crops and potato stores 2020

Appendix 3 - Definitions and notes

1) Pesticide information recorded in this survey relates to any pesticide usage during potato storage and to post-harvest applications, carried out in the field at lifting, prior to entry to the store. Pre-planting treatments with a fungicide intended to control disease post-planting e.g. black scurf, are not included, even if the fungicide had been applied in store. Use of pesticides in this situation is recorded in the seed treatment section of the preceding arable crop report.

2) ‘Pesticide’ is used throughout this report to include commercial formulations containing active substances (a.s.) used as herbicides, fungicides, insecticides, molluscicides, biological control agents, growth regulators, seed treatments and physical control. A pesticide product consists of one or more active substances co-formulated with other materials. In this survey, only fungicides and sprout suppressants (growth regulators) were encountered.

3) An active substance is any substance or micro-organism which has a general or specific action against harmful organisms or on plants, parts of plants or plant products.

4) In this report the term ‘formulation(s)’ is used to describe the pesticide active substance or mixture of active substances in a product(s). It does not refer to any of the solvents, pH modifiers or adjuvants also contained within a product that contribute to its efficacy.

5) A fungicide is a pesticide used to control fungal diseases in plants or potato tubers.

6) A growth regulator is a pesticide used to regulate the growth of the plant, for example to suppress the growth of sprouts by potato tubers in store.

7) A seed treatment is a pesticide applied to seed or potato tuber before planting to protect that plant against disease and pests from the earliest stage of development.

8) Basic tonnage is the quantity of potatoes treated with a pesticide, irrespective of the number of times they were treated or the number of pesticides used. This figure is used to calculate the percentage of potatoes treated with a given pesticide or pesticide group.

9) Seed potatoes are crops grown for marketing or planting as seed for next season’s crop. A fraction of the crop intended for seed production may not meet the necessary requirements and may be reclassified as ware potatoes post-harvest.

10) Ware potatoes are those grown for the ware (consumption) market, including those processed by a manufacturer. Ware potatoes may include a proportion of potatoes originally planned for seed production but later classified as ware.

11) Unventilated stores are defined as simple stores without fans that are naturally ventilated.

12) Ventilated stores can either be adapted ambient or purpose built ambient ventilated stores. These stores use forced air ventilation; they are not refrigerated.

13) Adapted ambient ventilated stores are basic stores with forced air ventilation. These stores commonly contain temporary fans and raised vents (normally wire hoops) on the floor of the store.

14) Purpose built ambient ventilated stores are purpose-built stores with forced air ventilation including open walled letterbox systems or suction wall systems. The potatoes are often stored to a depth of 3-5 metres; the floor is concrete and contains ventilation ducts. Pesticides can be applied by means of fogs and gases dispersed through the ventilation system.

15) Refrigerated Stores are purpose-built stores which may also have mechanically assisted ventilation. Potatoes are stored at low temperatures which can help reduce the use of pesticides. Pesticides can be applied through the ventilation system

16) Potatoes can be stored either in bulk (loose potatoes) or in wooden boxes. Potatoes stored in bags are excluded from this survey.

17) Ethanol is used as an ethylene generator to suppress tuber sprouting in stores. There is no standard recommended rate per tonne for the use of ethanol in potato stores and the quantity used varies according to store capacity, crop volume, type of store and duration of storage. In most cases the actual rate of application is not available and total quantity cannot be estimated. Therefore, estimated use of this pesticide is presented only as tonnes of potatoes treated.

18) In this report each estimated use of each pesticide is reported in three formats; tonnes treated with pesticide formulations (mixture of active substances in a product) and of individual active substances and quantities of active substance applied (Table 2 formulation data, Table 3 for active substance treated tonnes and quantity data). All three different formats are provided to satisfy the needs of all data users and allow them to assess pesticide use trends. Some users may be interested in use of pesticide products which contain a number of active substances, thus formulation data would be required. Other users are interested in particular active substances which may be formulated on their own or in combination with other active substances. Therefore, active substance data would be required. In addition, both quantity and tonnes treated with pesticides are important indicators of changes in use over time. Only single active substance formulations were encountered in 2020.

19) The June Agricultural Census⁽¹⁰⁾ is conducted annually by the Scottish Government's Rural and Environmental Science Analytical Services (RESAS). The June Agricultural Census collects data on land use, crop areas, livestock and the number of people working on agricultural holdings. For this report the June Agricultural Census was used to draw a sample of growers growing the relevant crops to participate in the survey

20) Throughout this report the term ‘census area’ refers to the total area for a particular crop or group of crops recorded within the June Agricultural Census⁽¹¹⁾. These are the areas which the sampled areas are raised to. Please see Appendix 4 for details. The June Agricultural Census Form is divided up into different categories which relates to a particular crop or group of crops. These are referred to as ‘census categories’ throughout this report.

21) Where quoted in the text or within figures, reasons for application are the grower’s stated reasons for use of that particular pesticide on that crop and may not always seem appropriate. It should be noted that growers do not always provide reasons; therefore, those presented in the figures only reflect those specified and may not reflect overall reasons for use.

22) Due to rounding, there may be slight differences in totals both within and between tables.

23) Data from the 2018⁽³⁾ and 2016⁽⁴⁾ surveys are provided for comparison purposes in some of the tables and figures. It should be noted that there may be changes in areas of seed and ware potatoes grown between survey years. Also, when comparisons are made between surveys it is important to take into account that there may be changes in quantity of potatoes stored.

24) For notes on quality and sources of bias please refer to the notes and definitions section of the preceding arable report.