Sunday, February 26, 2012

Grasshopper Trap

Researched a bit and learned of some known grasshopper attractants.  Canola oil, molasses and the color yellow.

Some insect traps I've seen consist of an illuminated plastic panel over a tub of water.  The insects fly toward the light, hit the plastic and fall into the tub.

Combining these ideas into my concept of a grasshopper trap...

For the past few years at my workplace there has been a pet garden spider nesting on the facility generator or the generations of the original spider's offspring.  I find it fascinating to catch a grasshopper to place in the spider's web and watch it go to work.  All the insect research I'm doing has sparked my memory of things to incorporate into designing what I think will work well as a trap.

Many times I've seen grasshoppers fly straight into a pane of glass or wall and fall straight to the ground.  If they are attracted to the color yellow as I've read and to the odor of canola oil and/or molasses, this concept should make a good trap.

The yellow rectangular riser, set into a collection funnel, is hollow with mesh ends.  We should be able to soak a rag or something with the attractant and have it hanging inside the riser so the odor vapors can freely circulate out of the mesh.  I can just imagine a grasshopper flying straight into the riser, perhaps thinking it might land on a food source but find the surface is too slick to grip and it simply falls through the gap between the riser bottom and funnel, into the bucket.

Worth a try!

To form a steep side funnel needed for this concept, suitable for attaching to a five gallon plastic pail lid I just discovered that coroplast will not bend enough to form the funnel shape when cut, so another material will be needed.

In the meantime, here is how to form a funnel or cone shape out of flat stock...

The top portion is showing starting with flat stock.  A flat, thin piece of wood is used for a marking jig by drilling three small holes. 

The bottom or set pin hole will determine the center starting point by which the lines will be drawn to form the pattern.  A small screw or nail will keep it in place in the exact center of our 3' wide stock, 3" from the bottom edge at all times during marking the lines.

2.5" up from the set pin hole we drill another hole large enough to insert the point of a pen or marker and likewise 17" up from the set pin hole we drill another marking hole.

Set the set pin and draw the lines, starting from the bottom edge of the stock on either side and go all the way to the other side.  The stock will need to be at least 20" tall, a little extra won't hurt and make it easier to cut out the final shape.

We should end up with a 34" diameter overall with a 5" diameter center opening.  Mark straight lines from the bottom corners to 2.5" up from the bottom to the center opening line and trim off as shown in the bottom portion of the drawing above.

If we use a flexible, smooth plastic material other than coroplast.  It will bend and form a cone or funnel shape with overlapping edges we can secure with rivets or drill holes and insert zip ties, keeping in mind to run them diagonally to prevent spots which might provide foot-holds for grasshoppers.  We don't want any escapees!

We should then be able to easily cut a hole for the funnel in a plastic pail snap lid. 

I will update this post when there is something to show and tell. :)

Ok here's an update of the built prototype as of 3/3/12...

Instead of using the original art concept I decided this configuration would provide more surface area and at the same time give a better opening below for any hopper that decides to fly headlong into the walls where "decoys" of yellow duct tape have been applied.  Will be trying this soon as hoppers start hoppin as it warms up.  Plan on using a canola oil spray as attractant. It's supposed to stimulate a cannibalistic feeding frenzy according to research.  

A view from above.  The bucket lid, funnel and decoy walls are all attached with zip ties.  A screened opening was made onto the bucket for viewing and ventilation.  Three holes are drilled at angles through the bottom and lower sides of the bucket to secure the whole unit to the ground with tent stakes in windy conditions. 


  1. Charlie, I was wondering how well your trap works? I assume since this was posted in February you have had a chance to test it? I am verry interested in finding a way to catch and collect grasshoppers.

    1. Hi, ummm no I have gotten busy with a project and haven't given it a proper test. Lots of hoppers out though so i should set it up and find out! Thanks for the reminder!


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