3 ms·

Interesting that higher concentrations can be less effective? Did I get that right? Sounds complex. And complexity doesn't always mix well with the virality / p

Interesting that higher concentrations can be less effective? Did I get that right? Sounds complex. And complexity doesn't always mix well with the virality / popularity of a narrative.

anenefan 4y ago
I should mentioned the coastal damage episode in a separate paragraph for clarity. The two herbicides are quite different, one kills woody weeds very effectively at minute amounts, the other is a residual grass type herbicide which can modify the action of other herbicides like paraquat. Sugar cane growing farmers in the region around my locale and to the south, including Mackay and Sarina, in the past frequently used the diuron herbicide mixed with paraquat when cane shoots had regrown a foot or higher after harvest or in plant cane to subdue and kill competitive grasses between the rows of sugar cane. Since most farmers are on a very tight budget it's applied generally in a manner that it stays on target, excess diuron that hits soil will bind with it ... however those using the dry formulation there was a significant risk, undissolved particles that might remained on dead plant material could have been flushed into streams by heavy storms (depending on landscape, more than 2 or 3 inches of rain in a moderately short period) and out to coastal areas. The decline in mangrove health, didn't make much sense to me where the river or outflow areas often didn't seem as affected as other areas ... illegal disposal seemed a better option ... but of course finding out a well funded group were using it to excess and the kicker was not over soil where excess might bind but in fact in a flowing river system, the real culprit seemed very obvious. Metsulfuron Methyl is part of a family of herbicides that kill woody plants at just a level tablespoon per acre, so one can expect a spill to wreck havoc. I became quite fearful of its use approx end 90s or early 00s after hearing and then reading of an incident reported in South Australia where an accident during its cartage had resulted in spill of the herbicide and subsequent wide area that was damaged. I can not find a reference to that online at the moment. What I found instead was a report of unintended off target damage, be that spray or other, no quick links specified how the herbicide found its way into the off target trees. [1] Around 2015 or so I realised that in good weather - appropriate spraying conditions, Metsulfuron Methyl is not very mobile in the soil profile, after someone mistook a near full pound box (half kilo) of the dry formulation herbicide in dissolvable satchels, for a diuron alternative and used the entire box in a spray mix to apply a two foot band over 400 to 500 yards of fence line. I was only informed three or four months later and I immediately went for a sticky beak expecting to see dead trees all around - to my surprise even a couple of new weeds had grown up in the sprayed band, not many but a few ... I made a point of checking for a couple of years to see if any acive product was mobile in the soil and affecting the trees close by. I didn't note any. [1] https://www.epa.nsw.gov.au/reporting-and-incidents/report-pollution/contacts-chemical-radiation-pollution/girraween-incident https://www.epa.nsw.gov.au/reporting-and-incidents/report-po...

Interesting that higher concentrations can be less effective? Did I get that right? Sounds complex. And complexity doesn't always mix well with the virality / popularity of a narrative.

anenefan 4y ago

I should mentioned the coastal damage episode in a separate paragraph for clarity. The two herbicides are quite different, one kills woody weeds very effectively at minute amounts, the other is a residual grass type herbicide which can modify the action of other herbicides like paraquat. Sugar cane growing farmers in the region around my locale and to the south, including Mackay and Sarina, in the past frequently used the diuron herbicide mixed with paraquat when cane shoots had regrown a foot or higher after harvest or in plant cane to subdue and kill competitive grasses between the rows of sugar cane. Since most farmers are on a very tight budget it's applied generally in a manner that it stays on target, excess diuron that hits soil will bind with it ... however those using the dry formulation there was a significant risk, undissolved particles that might remained on dead plant material could have been flushed into streams by heavy storms (depending on landscape, more than 2 or 3 inches of rain in a moderately short period) and out to coastal areas. The decline in mangrove health, didn't make much sense to me where the river or outflow areas often didn't seem as affected as other areas ... illegal disposal seemed a better option ... but of course finding out a well funded group were using it to excess and the kicker was not over soil where excess might bind but in fact in a flowing river system, the real culprit seemed very obvious. Metsulfuron Methyl is part of a family of herbicides that kill woody plants at just a level tablespoon per acre, so one can expect a spill to wreck havoc. I became quite fearful of its use approx end 90s or early 00s after hearing and then reading of an incident reported in South Australia where an accident during its cartage had resulted in spill of the herbicide and subsequent wide area that was damaged. I can not find a reference to that online at the moment. What I found instead was a report of unintended off target damage, be that spray or other, no quick links specified how the herbicide found its way into the off target trees. [1] Around 2015 or so I realised that in good weather - appropriate spraying conditions, Metsulfuron Methyl is not very mobile in the soil profile, after someone mistook a near full pound box (half kilo) of the dry formulation herbicide in dissolvable satchels, for a diuron alternative and used the entire box in a spray mix to apply a two foot band over 400 to 500 yards of fence line. I was only informed three or four months later and I immediately went for a sticky beak expecting to see dead trees all around - to my surprise even a couple of new weeds had grown up in the sprayed band, not many but a few ... I made a point of checking for a couple of years to see if any acive product was mobile in the soil and affecting the trees close by. I didn't note any. [1] https://www.epa.nsw.gov.au/reporting-and-incidents/report-pollution/contacts-chemical-radiation-pollution/girraween-incident https://www.epa.nsw.gov.au/reporting-and-incidents/report-po...