plus something that was relatively noise-free. In the end
I decided on the “DynaTrap Insect Trap.” This trap uses
the warmth and glow of a UV light to lure in flying insects.
It has a strong yet silent fan that vacuums insects into
a retaining cage. The one I bought provides
coverage for a half acre of property,
which is more than enough for my small
backyard.
YEAR ONE
In mid-August I positioned the trap
in a central location in my backyard. I
turned it on at dusk and turned it off
in the morning when I would gleefully
count the ‘spoils’ from the night before.
During the first weeks the trap was
capturing up to three or four moths a
night. Considering each moth is capable
of laying up to 6,000 eggs, I figured that
after one night I was already ahead of
the game. As the week progressed the
capture rate increased to as many as
seven or eight a night.
As the summer waned and turned to fall, this
number declined. By early October daily inspection of
the trap saw no moths. Finally, around mid-October, the
trap was retired for the season. Next year’s borer season
could not come fast enough as I was eager to see the
results of this experiment.
YEAR TWO
As the iris season started, my primary indication
that our borer population had been reduced was the
reduction in damage to the iris fans. Early evidence that
the iris borer larvae are present is notches in the leaves.
Previously when I noticed these notches I would cut the
fan down to the rhizome. This year I cut back 50% fewer
fans. It would seem our “DynaTrap” experiment was
working!
I also made another observation relating to when the
iris borer moth starts to fly. Most material I have read
states that the moth starts to fly in mid-August. However,
I found evidence to suggest it may begin earlier. In mid-
July, while I was tending a clump of irises a borer moth
emerged out of the ground and flew away. That night I
set up the trap to see what would happen. The following
day I had three borer moths. In the days that followed
only two or three additional moths were captured. After
that there was nothing until the end of August when
the number of captured borer moths jumped
dramatically.
Since early results of this experiment
were promising I bought a second
trap so I could have one in the
front yard and one in the backyard.
I’m sure my neighbors had borer
moths lurking on their property and I
wanted to capture as many as possible.
YEAR THREE
There was a further reduction in the
number of fans that needed to be cut
back due to borer damage. It was at this
point that I made yet another observation.
Since the second “DynaTrap” had been
positioned in an iris bed, I noticed that the
irises surrounding the trap had the highest
level of borer damage. I hypothesized that
perhaps the moth was laying its eggs before it
entered the trap. As a result I now position this trap in an
area away from my iris beds.
YEAR FOUR
In May, as I was sitting on the patio with my partner,
we both commented on the fact that our irises had
never looked healthier. Clumps of irises were larger with
a greater number of bloom stalks plus their foliage was
notch-free. The best part was that after three seasons of
using the trap my old “hobby” wasn’t consuming as much
of my time as it used to. The “DynaTrap” may not have
completely eradicated the iris borer problem, however, it
has reduced the numbers by approximately 90%. I would
recommend that iris lovers who live in “borer country”
try this method of control. It’s chemical-free and you will
also catch mosquitoes and lawn moths at the same time.
If you decide to get your own trap I would be
interested in your results. You can email me with your
story at tlaurin@rogers.com. Otherwise, if you have any
questions let me know. Happy borer trapping!
d
Summer 2018 AIS Bulletin 49