To: North American Fruit Explorers <nafex@lists.ibiblio.org>
Subject: [NAFEX] 2,4-D colateral damages
Date: Mon, 30 May 2005 07:55:38 -0400
Hi all:
Last year, we had a thread about the perils of using 2,4-D in the
proximity of grapes, tomatoes and other sensitive plants. It is getting
to be that time of year so I thought I would recap the high points of
the discussion.
The biggest offenders were ignorant neighbors and lawn care services
with broken givadamns. Still, there are a few NAFEXers around (like me)
who like to play with fire and 2,4-D. They are both useful tools under
the right circumstances.
General information:
The amine formulation of 2,4-D is far less volatile than the ester
formulation. The amine formulation is also far less volatile than the
"low volatility" formulation of the ester form, as well. Use the amine
formulation.
Spray at relatively low pressure. Lower pressures create bigger
droplets. Bigger droplets don't blow in the wind like finer mist.
Evaporation is sometimes blamed for simple wind-drift.
Spray in the cool of the evening. Good luck finding cool evenings
during July and August.
Precondition your water with approved farm supply chemicals.
Alternatives include using distilled water from the store, a tsp. of
swimming pool pH REDUCER, or a package of koolaid or other powdered kid
drink with citric acid in it. Conditioning spray water with kid drink
is not recommended if there are any kids around who might be tempted to
drink the spray!!!!
Final suggestion (and my own personal invention), add a cup of sugar per
gallon to your mix water before adding the 2,4-D. There is a chemistry
concept call "partial pressure". Suppose you have a mixture of one part
A to nine parts B. Then the amount of A that evaporates, at a given
temperature, will be 10% of what it would be if the there was no B in
the mix. The sugar will greatly reduce the partial pressure of the
2,4-D. Unfortunately, it will also slow the target's uptake of 2,4-D so
you will need an honest 24 hour no-rain window or you will be out of luck.