ENTRAZONE 400 WG – Fast action where weed control matters
Written by Robby Pienaar
Head of Technical & Product Development
Weeds do not need much time to become expensive. Whether competing with a young wheat crop or establishing beneath an orchard, broadleaf weeds intercept light, consume water and nutrients, and draw on resources that should ultimately contribute towards yield and quality.
The challenge becomes even greater when difficult broadleaf weeds survive the initial weed-control programme. A few scattered plants can quickly develop into established populations, replenish the soil seedbank and create a recurring problem for future seasons.
For farmers, effective weed management is therefore about much more than keeping fields looking clean. It is about protecting crop potential early, preventing weeds from gaining a competitive advantage and stopping difficult species before they become tomorrow’s problem.
This is where ENTRAZONE 400 WG provides a valuable additional tool.
1. ENTRAZONE 400 WG – targeted broadleaf weed control
ENTRAZONE 400 WG is a water-dispersible granule herbicide containing 400g/kg carfentrazone-ethyl, a triazolinone herbicide.
It is registered for the post-emergence control of broadleaf weeds in wheat and barley in the Western, Southern and Eastern Cape, as well as for directed weed control applications in perennial crops including deciduous fruit (apples, pears, peaches, plums and nectarines), table and wine grapes, citrus and macadamias.
What makes ENTRAZONE 400 WG particularly useful is its rapid contact action.
Unlike systemic herbicides that must move extensively through the weed before symptoms develop, ENTRAZONE 400 WG acts directly on the plant tissue contacted by the spray. The result is the characteristic rapid burn-down of susceptible broadleaf weeds following application.
But what actually happens inside the weed?
1.1) Mode of action: disrupting the weed’s cell membranes
Carfentrazone-ethyl is a PPO-inhibiting herbicide. ENTRAZONE 400 WG controls susceptible weeds through membrane disruption initiated by inhibition of the enzyme protoporphyrinogen oxidase (PPO).
Once this process is disrupted, susceptible plant tissue is rapidly damaged. The visible result is fast necrosis and burn-down of the foliage contacted by the spray.
1.2) Coverage matters
This speed is one of ENTRAZONE 400 WG’s most noticeable characteristics in the field – but it also highlights an important principle:
Because ENTRAZONE 400 WG works only where spray reaches the plant, coverage is critical. In wheat and barley, the label specifies ground application using a correctly calibrated boom sprayer delivering 200–400ℓ/ha, at 100–200kPa, to obtain even distribution.
In orchards and vineyards, approximately 200ℓ/ha spray mixture should be applied with equipment and nozzle selection aimed at achieving thorough weed coverage while minimising drift. Applications should not be made when wind speed exceeds 10km/h.
1.3) Broadleaf weeds in wheat: hit them while they are young
Early weed competition can compromise the establishment of a cereal crop before the full effects become visible. Allowing broadleaf weeds to develop alongside wheat means that moisture, nutrients, light and physical growing space are being shared during an important period of crop development.
ENTRAZONE 400 WG provides farmers with a post-emergence option for tackling this competition. The registered weed spectrum includes important species such as wild radish (Raphanus raphanistrum), spiny emex (Emex australis), musk heron’s bill (Erodium moschatum) and pimpernel (Anagallis arvensis), amongst others.
Timing remains critical. ENTRAZONE 400 WG should be applied while weeds are young, actively growing and not under stress. Weeds subjected to unfavourable growing conditions may be less susceptible, while applications made to young weeds provide a better opportunity to achieve thorough coverage before plants become large and difficult to control.
1.4) Not only for cereals – strengthening orchard weed control
Weed management beneath perennial crops presents a different challenge.
Orchard weeds have less direct competition from a dense crop canopy and may therefore establish substantial biomass. Difficult broadleaf species can also survive conventional knockdown programmes, forcing growers to make repeat applications or use additional control measures.
ENTRAZONE 400 WG can be used as part of a directed orchard weed-control programme in deciduous fruit, vines, citrus and macadamias. It is aimed particularly at difficult weeds such as small mallow (Malva parviflora), flax-leaf fleabane (Conyza bonariensis) and stinging nettle (Urtica dioica), with the ideal treatment stage being actively growing weeds approximately 10cm high.
2. Stewardship protects tomorrow’s weed-control options
Every effective herbicide should be treated as a resource.
Repeated reliance on the same mode of action places selection pressure on weed populations and increases the risk of resistant biotypes becoming dominant.
ENTRAZONE 400 WG should therefore form part of a broader resistance-management programme in which herbicides with different modes of action are rotated or appropriately combined. Fields should also be monitored regularly so that suspected resistance can be identified early.
3. Fast action. Proven performance. A valuable partner in weed management
Good weed control is rarely the result of a single decision. It comes from identifying the problem early, selecting the right product, applying it at the correct growth stage and ensuring that the spray reaches its intended target.
ENTRAZONE 400 WG combines rapid PPO-inhibiting contact activity with proven local field performance, giving farmers a valuable tool for the control of difficult broadleaf weeds in cereals and perennial crops.
When applied at the right time with good coverage and as part of a responsible weed-management programme, ENTRAZONE 400 WG delivers fast, reliable control where it matters most – protecting the crop and its yield potential.
ENTRAZONE 400 WG – hit difficult broadleaf weeds where it counts.