Moth sheet - What about the sheet?

Hi,
There is a lot of discussion about lighting to attract moths. But what about the sheet? Are there any recommendations from expert lepidopterists? I’ve read that some people use special sheets that fluoresce under UV light. This does not make sense to me. Fluorescence is the absorption of UV photons that are re-emitted in longer waves. With fluorescence, UV absorption typically emits blue, or green, which is why invisible light under UV makes the object fluoresce visibly bright. In other word, by using a fluorescent cotton sheet, we loose lots of UV radiations. It would make more sense to me to use UV reflective material like a textile with Teflon fibers. I have not read anything in the literature about this. Do you have any ideas?
Julien

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I’m not a lepidopterist, but I’ve used sheets, my t-shirts (a favorite - so easy), and the sadly departed BioQuip’s stand-up moth sheet and I haven’t noticed any differences. I think weather conditions, location, time of year, viewability of the light (line of sight), and a diverse local flora are probably the biggest factors when it comes to attracting insects. I’ve mostly thought of the sheet as a substrate for the insects to land on and make them easily viewable.

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The recommendation I usually see is a cotton sheet. Some of mine are 100% cotton. Lately, 60% Cotton/40% Polyester has been easier to find. Works the same for me. One of my friends has a piece of plywood he painted white. I have used the shiny metal siding of a garage a few times.

When wind destroyed my sheet, I have used a white panel that did not glow and hardly attracted anything. It wasn’t the best time of year for moths, but more showed up on the remains of the sheet nearby. I have read that moths are attracted to the light, not the sheet, but the material fluorescing seems to make a difference.

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Plain ol white bed sheet.

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I use a simple white cotton bedsheet. This is my setup from last year, which went pretty well.

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I haven’t used a sheet yet - nights are not my best time - but from what I see while identifying any plain white cloth will do. I’ve seen some with square weave. I believe the white simply spreads out one light source, and forms a substrate for night insects to land on.

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Some folks like nylon ripstop–particularly because it has a grid pattern (5 mm usually) that you can use to determine the size of the insect.

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Yeah, I think any white sheet would do the trick. White is useful in that it gives a nice plain background which highlights the moth or other insect. Other important thing is to make sure the sheet is secured with weights so that it doesnt blow about. The light which you use to attract moths ideally should be the brightest light source around, so you need to consider the moon as a contender. Other things like weather also factor, I don’t think rain and wind are favorable conditions, but rain can attract other sorts of critters.

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I go with a king sized cotton sheet. I’ve heard of people using dry erase boards too for ease of cleaning.

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Thanks @tiwane and @jciv for your feedback.
@mamestraconfigurata you wrote “I believe the white simply spreads out one light source”, but my point is precisely that cotton do not spread the light source in the UV wavelenghts (it absorbs UV and re-emit them in the human-visible light). So we spend money to emit UV (when using a LepiLED, for example) that we do not fully exploit.
But if the sheet is just considered a place for insects to land where we can easily spot them, ok.

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Ripstop. That was the term I had been trying to describe! The term actually came to me in the middle of the night.

I don’t know too much about the physics of light emission or reflection. Published in 1977, J.E.H Martin ( A42-42-1977-1-eng.pdf (publications.gc.ca) says the “usual” collection method is a white sheet on the ground or suspended vertically with a black light source over or in front of the sheet (p. 16). I did a quick search for light source effectiveness and found this for light traps - Microsoft Word - MEZVol5No1.doc.enson1 (researchgate.net). I suspect the use of a white sheet and UV light source is common because it is cheap, easy, and seems to work. Besides the above, I have no more information about sheet trap effectiveness!
I don’t even know who to ask for further information - I identify moths, and those who collect use either traps or sheets.

White cloth is a thing that people use without knowing anything about science or biology, e.g. to catch bats, moths fly to regular light pretty well, you don’t need only UV, so it works.

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Not stating anything new here, but…

I don’t know about the composition of the fabric, but if you’re thinking about getting yourself a sheet I recommend fabric with a grid pattern for the simple reason that it helps immensely with estimating size in photos.

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I have porch lights on either side of a large sliding door. I hung a sheet on one side and left the other side exposed (wood siding painted dark blue). More moths went to the dark side!
After experimenting with various lights, I settled on one soft white incandescent and one blacklight in each pair of lights in the front & back of my house. Different moths are attracted to each light.
Hey, my neighbors think I’m nuts, but I’m happy. With the exception of the subtle peer pressure to submit photos with a white background. I’m in therapy for that…LOL :grin:

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Interesting experiment! As a moth identifier, it does not matter to me what the background is, as long as the moth is ‘legible’. Cancel that therapy! :grinning_face_with_smiling_eyes:

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Thanks for the reassurance. I think my photos have improved, but am always open to general critiques and suggestions.

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