Ahri Snapshots

Some excellent research conducted by Stephen Hole, under the watchful eye of Professor Steve Powles at the University of Adelaide in the mid-1990’s investigated the microbial degradation of propyzamide and another similar herbicide, carbetamide. Enhanced microbial degradation is where the soil bacteria that can eat a particular herbicide build up to very high levels so when the herbicide is applied it is broken down very quickly, effectively reducing the half-life of the herbicide.What they found was:Where carbetamide or propyzamide were used twice in the same winter growing season, the second application was roughly half as effective as the first.In another study, carbetamide efficacy was reduced from one growing season to the next when it had been applied to a field for seven consecutive years prior to the field research.Four years without carbetamide returned soil bacteria levels to similar levels to untreated soil.What has not been found so far:Any evidence of enhanced degradation of propyzamide that pers