Question

[Tim Mangan-Kansas]

About a week ago, landlord Ross Blanchard made a post on one of the facebook forums about wet nests in gourds. Following is a portion of his post.

"One of the biggest sources of moisture is the drain holes. Before you dismiss this, run a simple test. Make sure hanging holes are plugged. Put a tissue in the bottom of the gourd and simulate rain for 5 minutes. Water surface tension on a sphere gets faster on slick gourds. Water sticks to the sphere until it encounters a surface that breaks the surface tension (I.E. drain holes plus water rushing from other sides of the gourd.) It looks like a 1/2 fountain inside the when it's raining hard. With the wick effect on the nest materiel you have a soaked nest in the matter of hours. A wet nest turns into a breeding ground for the mites and the gourd becomes a steam room in the heat. Gourds that swing free have a real problem when you combine strong wind and hard rain. The wind forces the gourd to hang at an angle and water flows directly into the nest area thru the drain holes. Possible fixes, plus, how I have kept my gourds dry and mite free for the last 3 years.
1. Flooring inserts at least 1/2 in. Helps but wick effect in some cases.
2.Sand paint the whole gourd. Breaks up water surface tension but wick effect in some cases.
3. Plug the drain holes. Works quite well but it makes me nervous. Unique weather in the South could create conditions where you need the water drained.
4. What I do that works.
a: Use 4" PVC and cut 1in. length and glue with LEXEL around drain holes.
Works well with gourds that swing free.
b: Use top from cottage cheese cup cover and cut the center out and glue with LEXEL around drain holes. Works great on Troyer Horizontal but only lasts 2 years because sun and weather.
c: My current favorite. Screening Spline used to keep wire mesh in frames. Make sure it is the rough kind because the water jumps over the smooth. Put a circle of LEXEL glue around drain holes and put your spline materiel on top of glue.
d: 1/2 in cable. Works but very hard to install.
e: Sphere type gourds with drain holes must be mounted solid."

What he states makes sense to me and I plan on making a modification to my gourds in the off season regarding the bottom drainage holes on my THG's. I have been thinking of possible alternatives to the screen spline and cup covers. My question is, do you think putting a piece of traction tape over the drainage hole and then re-drilling the hole through the traction tape would have the same effect? Any other thoughts as to what might work?

Tim

[Matt F.]

Gourds that swing free have a real problem when you combine strong wind and hard rain. The wind forces the gourd to hang at an angle and water flows directly into the nest area thru the drain holes.

Great findings by that gentleman Tim!
The two things that make me think to the contrary however, of what he stated in reference to swinging gourds are:
1. The rain is going to be falling in the same direction as the wind that's pushing the gourd, so the swinging gourd's bottom will always be pointing away from the rain.
2. I would also think that the centrifugal force (though mild) generated by the swinging action of the gourd, would assist in expelling any water that did get in, out through the drain holes.

[Tim Mangan-Kansas]

Matt:
Appreciate the reply. At my site, all of my gourds are mounted so they do not swing during high winds.

Tim

[Mhoover]

Maybe gluing a piece of nylon mesh screen over the holes would break up the sheeting effect and allow the rainwater to fall away from the gourd before it reached the drain holes. The nylon mesh would also leave the drain holes open enough for water to drain out if it collected in the bottom of the gourd as well as allow air to enter the gourd and help dry out the wet nest material.

[DornCounty]

seems this theory would be easy to confirm with a nest cam.

If it does prove to be true.. this could be relatively easily designed out of new gourd with a "drip Edge" around drainage holes.

[blanchar40]

Matt F. the problem isn't centifugal force. It is water surface tension on a slick globe surface. It sticks like glue. Even dew ends up at the bottom of the globe. Uneven drain holes don't have to use the wick effect - water just flows in.

[Matt F.]

Matt F. the problem isn't centifugal force. It is water surface tension on a slick globe surface. It sticks like glue. Even dew ends up at the bottom of the globe. Uneven drain holes don't have to use the wick effect - water just flows in.

Got it.
That is a really great set of findings, and solutions you put together.
Prior to your report, I would've never have thought of water traveling up, and into the drain holes, like you found.

[blanchar40]

My question is, do you think putting a piece of traction tape over the drainage hole and then re-drilling the hole through the traction tape would have the same effect? Any other thoughts as to what might work?

Tim

Tim - If you by traction tape you mean the anti-skid tape with sand on it, then I think it will work well. I had an Excluder gourd up this summer with 1 drain hole in center surrounded by anti-skid tape. No moisture, no nest changes, & 6 fledges. I plan on testing this with more holes next year.

[Tim Mangan-Kansas]

Ross:

Yes, that is what I meant about the traction tape. However, instead of placing it around each drainage hole, I was going to put the tape over the holes and then make new holes through the tape.

Tim

[4th Gen Martin Fan]

Tim/Ross,
Are you proposing the traction tape on the outside of the gourd?
Mark.

[Emil Pampell-Tx]

Matt F. the problem isn't centifugal force. It is water surface tension on a slick globe surface. It sticks like glue. Even dew ends up at the bottom of the globe. Uneven drain holes don't have to use the wick effect - water just flows in.

What are uneven drain holes? I have mine in a circle at the bottom of the gourd.

It also may depend upon the size of the drain holes. I use some 3/8in and some 1/2in holes. I find it hard to picture water running up into the drain holes on my gourds, which are fixed so they do not swing..

I use pine needles, and I do not think that they have the wick properties.