Andermatt Biocontrol PheroNorm TMA Mode D'emploi page 18

TETRA
Pheromone trap for monitoring the Swede midge
( Contarinia nasturtii )
Background
The Swede midge attacks all species of brassicas, but also
rapeseed and other cruciferous plants. It has 3 – 5 genera-
tions per year. Wind protected and moist places are most
prone to attack. At the beginning of May the first generati-
on of the swede midge flies in from fields in which brassicas
rapeseeds have been grown the previous year.
Numbers of traps
Two pheromone traps per plot ( replace the trap case and
the lure after 4 – 6 weeks )
Positioning
About 2 m from the edge of the plot. The traps should
be placed as close as possible to plots that were planted
with brassicas /rapeseeds in the previous year. Recommen-
dation: Clearly mark the location of the trap in order to
relocate it.
Installation instructions
Keep pheromone dispensers sealed in original bags in
freezer until use! Fold the trap by bending the two sides
along the main prescored lines ( raw side outside ). Close
the trap at one upper corner with a staple. Place the lure
in the center of the trap and staple it ( the capholder should
hang freely in a vertical position about 0.5 –1 cm over the
bottom of the trap ). Then staple the remaining trap corner.
Attention: Do not touch the lure with your fingers, as this
will reduce its efficacy. Remove the laminated sheet of the
sticky paper, slide it with the sticky side up into the trap
and attach it with a paperclip on one side to the bottom
of the trap.
Time of application / damage point
Treatments should be carried out if needed at the onset of
Swede midge flight activity.
As a warning system, flight can also be monitored in last
year's cabbage plots. The timing of treatments for a cab-
bage / brassica plot should be based only on midge flight
activity in that specific cabbage / brassica field. Depending
on distance between plots, Swede midges can take from
several days to over a week to travel from a previous
year's plot to a newly planted cabbage field.
The sticky paper should be replaced at least weekly, during
the flight period. Important: Do not fold the ends of the
trap upwards! To hang the trap you can use a 60 cm long
bamboo stick. Attach the trap with the enclosed piece of
wire to a nail or a slit in the wood and stick the bamboo
at an angle of about 60° into the ground. The trap should
hang about 30 cm above the ground. If the sticky paper
gets too dirty, replace it with a new one. The lure remains
active for about 4 – 6 weeks. After this period the lure and
the trap should be replaced.