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Below trial was developed based on the United Kingdom Health and Safety Regulatory Update 21/2013: Appendix 2, to show that Orchard Agri Chemicals' snail bait pellets can handle rain

Venue: Roodebloem Farm, Caledon, South Africa (an area typically associated with a high risk of snail and slug attack)
Trial period: 28 October - 25 November 2015

The assessment method was primarily developed to support and differentiate between any claims made in relation to ‘showerproof’ or ‘rainproof’ properties of molluscicide pellets. (NB ‘rainproof’ is considered more challenging than ‘showerproof’). The arenas were subjected to a rain schedule to replicate either a 4mm daily rainfall pattern ("showerproof"), or a 10mm ("rainproof") daily rainfall pattern over a 14 day period, dependant on the claim being supported.

As a secondary outcome, snails were introduced at 14 DAT (Days After Treatment) to demonstrate the snail bait pellets' viability from this point. The daily rain schedule continued during this time on the same basis as the initial 14 day period. Mortality to the introduced snails was assessed at 15, 17, 21 and 28 DAT. It should be accepted that the pellets would be more effective from 0 - 14 DAT.

The conditions emulated by the trial attempted to reflect realistic field and weather conditions as much as possible.

Description

• 1.0m x 1.0m wooden field cages were constructed and the cages were placed in an open field area and covered with 70% sunlight block shade netting lids.
• Loam soil from the area was placed in the 1.0m² cages.
• Depth of the soil layer was sufficient to permit a degree of absorption of the applied water, to avoid ‘standing water’ on the soil surface.
• To reduce edge effects and to enhance representativeness, a cage size of 1.0m² was used.
• The arenas were plant free to prevent the possible sheltering of the pellets from the “rain”.
• 8 grams of each product was evenly applied per cage directly to the soil surface at DAT 0.
• The 101, 201, 301 & 401 "showerproof" test arenas were subjected to a rain schedule to replicate a 4mm daily rainfall pattern over a 28 day period.
• The 102, 202, 302 & 402 "rainproof" test arenas were subjected to a rain schedule to replicate a 10mm daily rainfall pattern over a 28 day period.
• The daily "shower" or "rain" event was applied as a single event at 10h00 in the morning.
• The “rain” was evenly applied with a micro sprinkler over the arena area and the rate of application did not exceed 0.5mm per minute.
• The water used was tap water.
• A treatment of ‘no rain’ was included in arena 501, to highlight and explain whether any other factors of the trials conditions are adversely affecting pellet integrity/degradation.
• Standard pellets with traditionally lower showerproof/rainproof properties were included in arena 101 & 102. This facilitated the demonstration of enhanced pellet integrity for formulations with shower/rainproof properties, in comparison with the decline of pellets susceptible to degradation under rainfall events.
• After showerproof/rainproof properties were determined, fresh populations of Brown Garden Snails and White Snails were introduced at 14 DAT to demonstrate the pellets viability from this point. Mortality to the introduced snails was assessed at 15, 17, 21 and 28 DAT.
• Although each cage had a lid, a 5.0m border area around the cages was also baited to prohibit free roaming snails, slugs and isopods from entering the test cages.
• All dead snails and slugs were removed throughout to an isolated container inside the relevant cage and kept for record keeping.
• General weather conditions was recorded on a daily basis and included in the trials report.
• During periods of heavy rain, all the traps were covered with plastic to protect them from heavy rain.
• The assessment schedule consists of a mean score of pellet integrity.

Weather
The following weather data was recorded at Roodebloem's weather station from 28 October 2015 to 25 November 2015:

• Total Rainfall: 42.4 mm
• High Air Temperature: 33.2 ºC
• Low Air Temperature: 7.5 ºC

The average temperature was high over the test period. This allowed the pellets to dry out between irrigation times. It is likely that this reduced the deterioration of the pellets. The test will be repeated during winter to compare the deterioration under cooler moist conditions.

See Appendix A for complete weather data.

Results
In terms of determining whether the data demonstrate ‘shower/rainproof’, it is not possible to be prescriptive in this report in terms of an absolute number as much depends on the scale and types of assessment used.

But, however assessed, the data was able to demonstrate a significant delay or a significantly slower rate of decline in pellet integrity compared with a reference product and that for the duration of the test the integrity remains such that the snail bait pellets are still viable, palatable and unlikely to significantly disappear into the soil structure.

Mold
Mold growing on snail bait pellets will make them less appetizing for molluscs and will cause snail bait pellets to deteriorate faster. On day 6 of the Roodebloem trial, we witnessed significant mold growth on both our competitors' products.

IMAGES of Arena 101 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 102 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 201 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 202 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 301 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 302 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 401 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

IMAGES of Arena 402 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

Images of Arena 501 at DAT 1, 3, 7, 10, 14, 15, 17, 21 & 28

Appendix A
Download the rainfall charts for Roodebloem over the test period
October rainfall chart.pdf
November rainfall chart.pdf

Table 1 Pellet decline at 14 DAT

 Table 2 Number of dead Brown Garden snails (n=10) at 15,17,21 & 28 DAT

Table 3 Number of dead White Dune snails (n=10) at 15,17,21 & 28 DAT

 Table 4 Total Number of dead Brown snails (n=10) after 28 DAT

 Table 5 Total Number of dead White Dune snails (n=10) after 28 DAT

Table 6 Total Number of dead Brown and White Dune snails (n=10) after 28 DAT


Table 7 Total Number of dead Brown and White Dune snails per product (n=20) after 28 DAT


Key Findings of primary test (0-14 DAT)

• Sluggem Prima showed the least amount of deterioration over this time
• Sluggem Standard ranked second, followed by Competitor A
• Competitor B deteriorated the most over this time

Key Findings of secondary test (14-28 DAT)

• Sluggem Prima and Standard killed the most amount of brown and white snails, followed by Competitor A. Competitor B ranked lowest on this criteria.
• Competitor A killed the most amount of brown snails, followed by Sluggem Standard and Sluggem Prima. Competitor B ranked lowest on this criteria.
• Sluggem Prima killed the most amount of white snails, followed by Sluggem Standard and then Competitor A. Competitor B ranked lowest on this criteria.