Growers are being advised to stay vigilant for willowherb and to take action to control the weed in cereal crops this spring.
Neglecting the issue early in the season could lead to significant yield losses at harvest, according to agricultural sciences company FMC.
Willowherb has become a more prevalent issue in recent years, most likely due to the shift towards minimal tillage or no-till methods.
These practices help soil structure, but they also provide an environment where certain weeds, including willowherb, can thrive.
Mathew Hutchings, commercial technical manager at FMC, says the absence of deep soil cultivations allows perennial weeds like willowherb to spread and establish roots deep in the soil.
“Changes to crop rotation patterns may have also caused the spike in willowherb being identified by agronomists,” he explains.
“The lack of options for control in some crops, especially those that are less competitive, may allow willowherb to spread and become more prevalent."
Mr Hutchings explains that the waxy coating on willowherb leaves serves as a natural barrier, limiting the absorption of certain herbicides.
This is especially evident with glyphosate, as the wax layer can repel the herbicide, hindering its ability to penetrate the plant tissues effectively.
The most effective way of tackling willowherb, and other broadleaf weeds this spring, will be to use sulfonylurea herbicides (SU) with the active ingredients metsulfuron and tribenuron, adds Mr Hutchings.
“Using an SU such as Ally Max SX will tackle the weed by quickly slowing down the rate of growth, before they become competitive," he says.
“SUs have been a key component of the arable toolbox for 40 years and to this day they continue to prove themselves on-farm.
"The enhanced spectrum of weed control they offer for spring cereal crops is invaluable and they should continue to be used even when new weed challenges appear.”
