"Chris Hogg" wrote in message
...
On Fri, 14 Nov 2008 05:52:25 +0000 (GMT), wrote:
In article ,
cineman wrote:
I seem to recall being informed that farmers use a herbicide on the tops
of
potato's to stop any further top growth, and leave tubers in ground for
storage.
Is this still the practice?
Yes - it's to prevent blight from getting into the tubers. But it
worn't do any harm, as it's only sulphuric acid - which is volatile,
won't affect the tubers, and wouldn't matter anyway!
I balked a bit at 'only' sulphuric acid, as if it was fairly harmless
stuff, although I suppose the OP is concerned about residues from more
sophisticated defoliants contaminating his compost heap.
My neighbour, a farmer, regularly sprays his potato top growth to kill
it. The haulms are actually desiccated, which requires strong acid,
and is quite nasty stuff. It can only be sprayed by a licensed
contractor with rather specialised kit (corrosion proof at least!).
Nor is sulphuric acid volatile (unlike e.g. hydrochloric acid). I
presume it eventually washes into the soil and is either neutralised,
if the soil is alkaline, or contributes to the natural soil acidity,
if not.
But conventional herbicides are also used, e.g. paraquat or it's
agri-equivalent, although they tend to be more expensive. I imagine
the choice depends on the availability of a licensed contractor and
what the overall costs and convenience are.
Which, if either, do 'organic' farmers use, I wonder.
Until very recently I worked as a sower/weeder/harvester/picker of various
crops for a local organic farmer. He doesn't use any of these chemicals.
The potatoes were planted using a small narrow tractor where one drove and
another two dropped the seed potatoes down a couple of chutes off the back.
When it came time to weed, the same tractor was used to churn up the weeds
between the rows. The difficulty was weeding across the rows (that is,
between plants), which we sometimes had to do by hand if there was a bad
infestation of e.g. thistles, which took time.
The potato haulms died off by themselves naturally in the autumn, and then
on one or two days the farmer had a harvesting party: he seconded as many
workers and their friends as he could muster, we all brought our sandwiches
and stuff for the day out, and he drove down the rows of potatoes using a
sort of chain thing attached to his tractor, which dug into the soil and
rumbled all the potatoes out of the soil, and then a gang of us followed
along behind picking the potatoes into skips which we would unload into a
barrow on his tractor for storage in a barn. The potatoes were stored in
heaps on the cement floor of the barn, covered with straw and sacking to
keep out the light. And yes, he paid us too!
I had a wonderful time working there, it was only a couple of years ago that
I gave up because of non-work-related health problems. I know it sounds
like something out of the 19th century, but I loved it. We buy a lot of our
veg. even now from him.
someone