Lanzarta Hylobius control - Your Questions Answered

Lanzarta is approved in the UK for both nursery treatment (one application), prior to planting out in the forest, along with up to two applications to the growing trees in the forest. 

Lanzarta works primarily through ingestion. When the weevil feeds on treated plant tissue, it ingests the active ingredient which disrupts muscle function; that prevents further feeding and eventual fatality.

Once a foraging weevil has consumed Lanzarta treated bark the action to stop further feeding is relatively quick. You may still see some activity of affected weevils on trees, but they will no longer be feeding or causing further damage. Over a period of days the weevil will die.  

Lanzarta provides a long residual action, with trials showing efficacy up to 4-5 months after treatment.

Nursery application is the treatment of lifted bareroot saplings using a closed cabinet application technique, before they are planted out into the forest. 

For nursery application Lanzarta must be applied using a closed cabinet system. Spray equipment should be set up and calibrated to apply the label approved rate of 6 ml of Lanzarta concentrate per 100 trees. 

Use a recommended spray mixture of one litre of Lanzarta product in 333 litres of water (0.3% solution), apply at a rate of two litres of pre-mix solution per 100 trees. 

Lanzarta protects the bark of the sapling from insect feeding damage. The aim is to target the entire stem bark and to retain the spray on the stem. 

Avoid spray from hitting the root zone of the sapling during treatment or running down onto the roots. Do not over wet the stem bark with excess spray solution that could lead to run off and wasted product. 

The recommended application  rate of two litres of 0.3% pre-mix solution per 100 trees should minimise the risk of spray loss.

Lanzarta treated saplings can be planted out as soon after treatment as required. Holding treated saplings for transplanting in cold storage will help to retain the efficacy of Lanzarta for longer after planting. Treating saplings destined for high-risk situations later in the season will maximise early protection in the forest. 

Where trees have been treated in the nursery before planting out, forest applications should not be made until at least 60 days after planting. 

In practice, saplings should be adequately protected by the nursery application for the duration of this period (typically 4-5 months protection).In most seasons and situations, plantings are unlikely to come under intense weevil pressure during this time.  

This will be entirely governed by the level of pest pressure and the forester’s assessment of damage risk. The nursery treatment is intended to give effective early protection, but if heavy infestation is identified or the risk is very high, an application later in the season may be required. 

Only one application of Lanzarta is permitted in the forest in any one season, irrespective of whether a nursery treatment has been applied or not.

Only two in-forest applications of Lanzarta can be made in the lifetime of the tree for Hylobius control. It is up to the skills and experience of the forester or agronomist to decide when those two applications are made to best protect any specific site in the early years of establishment, according to specific situation or seasonal pest pressure. 

The label caveat is that only one Lanzarta application is permitted per calendar year and a minimum of 180 days between applications.

No, a maximum of two applications can be made in the forest for Hylobius control in the lifetime of the tree.

Lanzarta is approved only for knapsack application in the forest. Mix Lanzarta at a rate of 3 ml of product per litre of water (0.3%), and apply 20 ml of the diluted spray mix per tree.

Do not apply more than 180 ml of Lanzarta product per hectare - equivalent treating  3000 trees per ha at a rate of 20 ml/tree using a 0.3% diluted spray mix. For higher stocking densities adjust the application rate per tree to avoid exceeding the maximum application rate. 

Accurate application is a key factor in the success of Lanzarta control of Hylobius damage. The aim of the treatment is to provide all round coverage of the entire bark of the sapling, to optimise control of adult weevils feeding on the bark.

Coverage at the stem base and branch nodes is especially important.

Syngenta application trials and independent research in the UK indicate that using a narrow fan pattern nozzle can achieve higher levels of product deposition on the target stem. 

Treatment to both sides of the sapling would expect to see higher all round spray deposition, although in trials the results showed no significant difference in levels of damage compared to spraying on just one side.

Targeting of spray at an angle to the upright stem will significantly increase coverage of the bark, compared to spraying from directly above the plant only,

Experience of treatments in Europe suggest the use of twin-nozzle horseshoe design lance attachment could provide improve all round coverage of the sapling.

In all instances the operator’s skills in accurately and consistently delivering 20 ml of spray per tree is recognised as crucial, which emphasises the importance of training and regular checks.    

Operators should refer to the label and respect the guidelines regarding suitable protective clothing when handling the concentrate or applying the product.

In trials, Lanzarta has shown superior efficacy compared to standards indicating a 60% reduction in incidence (number of bites) and an 85% reduction in the severity (how damaging the bites were).

Lanzarta has an excellent environmental profile. It has low impact on beneficial insects when used as directed.

As with all pesticides, proper resistance management is important. The unique mode of action of Lanzarta and the limited number of applications help to manage this risk.