CLomazone
Trade Name: Command 360 ME
Registration status: This herbicide is not registered for use in orchards.
When to suspect injury: Injury from herbicide residues may occur in newly-planted orchards when cucurbits or soybeans were grown in the previous year, or between young trees. Injury from drift from neighbouring fields may occur under windy conditions. If you notice symptoms of bleaching, especially in the growing point, look carefully at neighbouring fields, and at weeds in the treated area.
Herbicide Information: Knowing how the herbicide works will help to determine the likelihood of injury from either direct application or drift. Consider how the herbicide works in plants, behaves in soils and what symptoms are common in other plants.
Chemical Family: Isoxazolidinone
Site of Action/Group: Diterpene synthesis inhibitor (WSSA Group 13)
General Symptoms in Plants
- Following PRE emergent application in neighbouring fields
- Susceptible weed seedlings emerge but are bleached and after a few days become necrotic
- Following POST emergent application
- Susceptible annual species at later growth stages may show signs of foliar bleaching
Symptoms in Fruit Trees
- Where drift is suspected, leaves will show bleached spots where spray droplets landed
- If trees are planted into land previously treated with clomazone, growing points may show bleaching if residues are high enough
Uptake and Translocation
- Primarily absorbed through the roots
- Translocated through the xylem in the plant
Persistence
- Soil texture impacts residual and product efficacy
- Some rotational restrictions apply
- Relatively immobile in soil; microbial decomposition is the main path of dissipation
If you suspect herbicide injury, laboratory analyses of herbicide levels in plant tissue are necessary to confirm the presence of herbicides, although symptoms may be helpful in diagnosing which herbicides caused the problem.
Both damaged and healthy plant tissues should be analyzed, because comparison levels are not readily available for many herbicides. Contact your lab for instructions on which plant parts should be sampled, how to handle and ship the sample, and what costs are involved to ensure an accurate and timely diagnosis.
