The Blue Scale Card is disposable cardboard with the standard UC grid design, which facilitates counting of the trapped Western flower thrips (Frankliniella occidentails). The card comes pre-coated with Stikem glue and is folded in half so that the glue is on the inside. To activate, reverse the fold (to glue-side out) and attach the wire. The Blue Plastic Card can also be used to trap Western flower thrips. FlyTac (sold separately) is applied to the surface of the Blue Plastic Card to make it sticky. The semiochemical lure is attached to the wire, which is used to hang the trap on the crop.
The semiochemical-impregnated disc, used to attract the Western flower thrips to the scale card, is known as the W.F.T. PheroLure®. The W.F.T. PheroLure® needs to be replaced every six (6) weeks. Any additional W.F.T. PheroLure® should be kept in their individual foil pouches in a fridge in order to prolong their shelf life before use.
How, where and when to hang traps
- How: Always hang the card 1.2 to 1.8m high and 30cm into tree line for tree crops, or above the crop canopy in case of row crops. The W.F.T. PheroLure® should hang 90mm above the scale card, preventing it from touching the card. This will allow for maximum airflow, to distribute the semiochemical molecules (which are heavier than air), across the orchard/field. Hang the trap out of the way of farm implements, the direct reach of spray machines and irrigation systems, as well as away from roads, as the dust will cover the sticky liner and dry out the glue. Secure the trap firmly to the pole/stand/plant so that it does not sway in the wind. Identify each trap by a trap/block number for later reference.
- Where: A layout of the field/orchard will assist in the correct placement of cards. In fields that are uniform with respect to topography, size and windbreaks, hang traps at a density of 1 trap per 1 – 2 ha. This is the maximum area that can be monitored by a single trap. A higher density may be necessary in unevenly shaped fields/orchards, fields/orchards with excessive slopes or hollows where the prevailing wind may adversely affect trap catches.
- When: Tree crops: at beginning of production season.
Field crops: one week after germination or transplanting date.
Inspection and maintenance of traps
- Inspection: The cards should be inspected weekly on the same day of each week (7-day intervals). Cover the sticky sides of the plastic card with cling wrap. Avoid creases in the cling wrap for easy identification of insects. The number of Western flower thrips caught on the card, together with the card number and date needs to be recorded.
- Maintenance: Collect cards once a week and replace with new scale cards. Move W.F.T. PheroLures® to new cards. Only replace W.F.T. PheroLures® every six (6) weeks.
Disposal of lures
W.F.T. PheroLures® need to be replaced every six (6) weeks. Used W.F.T. PheroLures® can be disposed of in the garbage. No special precautions are required as W.F.T. PheroLure® is considered of no concern to human and environmental health.
W.F.T. PheroLure® is sold in individual foil pouches at 3 per bag.