UV light traps - how far above the ground?

[Leptraps at aol.com]

I think I can add a little to this discussion.
 
I have been using traps, both light and bait for many years. Here are a few
suggestions.
 
Light traps will work whether up in a tree or on the ground. However, if they
are placed on the ground and surrounded by vegetation, the light will be
blocked limiting the effect of the trap. I have hung em high and hung em low.
Keep them in a cleared area, whether on the ground, on a stand, or in a tree.
 
When I trap in a prairie the light trap is raised to provide better
reach/distance for the light. I use metal stands 28" tall. Wind on a prairie
will below the ethyl acetate out of the trap causing a poor kill and serious
damage to the specimens. I baffle my traps in the pail to reduce the effects
of the wind. It will also help if the ethyl acetate containers are near the
top of the trap. Ethyl acetate is heavier than air and will disperse more
evenly when raised to the top of the pail (Behind the funnel is the best
location).
 
Raising a trap into a tree will general not increase the total number of
insects that will be drawn to the light, it will however, on occasions,
increase the number of species of moths and you will also take more females
(I have no real explanation for this phenomena). Wind has a far greater
effect on a trap hung up in a tree. Beside the effect of the wind on the
ethyl acetate, the trap will spin and sway. Even when well tethered. Violent
storms with high wind can knock the trap out of the tree. Also, make a
flapper for the exit of the rain drain when you suspend them. This prevents
wind from passing through the trap from the bottom. This will draw out the
ethyl acetate much more rapidly than from the top.
 
You may also try a "Black Light Black" bulb (Dark purple). You will attract
different species due to a different UV light pattern. HomeDepot currently
has the dark bulbs for $9.99. This is a real bargain. The last ones I
purchased were in excess of $29.00 per bulb.
 
I should write a book on this subject!
 
Cheers,
 
 
 
Leroy C. Koehn
202 Redding Road
Georgetown, KY  40324
Tele.: 502-570-9123
Cell: 502-803-5422
E-mail: Leptraps at aol.com
 
"Let's get among em"
 
 
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