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Mosquitoes in water butts - olive oil?
JLodge
Posts: 26
I have discovered several mosquitoes in my water butts, after a search online even with a tight fitting lid they still find a way in. So the alternative is a tablespoon of olive oil to create a barrier so that the larvae can't breathe when in the water. The advice is to 'skim' the oil every few weeks, but I haven't found anywhere how you're meant to skim the oil off. Can anyone advise please?
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I use the smallest amout of soap &/or washing up liquid. The larvae use the surface tension to cling on. So little that I just leave it. It's biodegradable.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
As an aside, I have 2 x 200L butts and a 600L IBC daisy chained in that order, the overflow for the IBC goes into a 100L butt which acts as a buffer tank for the dripper hose that waters all of my hedging. I initially just had the IBC overflow going straight to the dripper hose but found out pretty quickly that a buffer tank was needed.
Just a drop on the finger is enough. You can see it spead out, and the larvae sink and drown. Very satisfying.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
They are all basically the same type of chemical. They all reduce the surface tension of water. A dish washing up liquid would emphasise detergency, that is the emulsification of fats. A foaming agent would create foam that in machine dish washer would be unnecessary, but in hand dish washing would show when its action is becoming exhausted. A rinse aid would emphasise the reduction of dish-to-water tension which is related to viscosity, so that the water drains quickly.
In something as crude as mosquito larvae-killing whatever you have to hand is good enough. I use liquid soap in my bug spray, just because I had bought that for some other horticultural reason. Normal household soap or detergent is OK.
Coincidentally surfactants also can act to prevent insects breathing. A bit like olive oil, but a different mechanism.
I hope that this is understandable. Please ask if I can expand on any aspect.
BTW. What can you tell me about water drop photography? In a current TV commercial, a coin is thrown into the Trevi Fountain. The upward bounce of the water (there must be a technical term) does seem to be particularly high.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
When I first attempted drop art I realised pretty quickly how difficult it is to capture the drop, so bought a specialist bit of equipment that you connect to your shutter trigger so that you can dial in the timing as well as alter different aspects of the drops. The base liquid needs to have lower surface tension (dishwasher rinse aid added) and the dropped liquid needs higher viscosity (Xanthan Gum added). I like to use a UV light source, so modified 2 flash guns to only emit UV and used Tonic Water as the drop liquid.
I also included a non-drop art image of a sunflower that I did using UV light (UVIVF - UltraViolet Induced Visible Fluorescence).