Chemical and Non-chemical Control Options for Hylobius

Pine Weevil (Hylobius abietis) are a major problem on forestry restock sites and a particularly heavy outbreak can destroy up to 80% of plants.

Historically, plants were sprayed with insecticides either on the nursery or in the field in order to prevent or limit attack, however, there are increasing calls for the use of chemicals in the natural environment to be restricted meaning that alternative options need to be explored.

At Alba, we provide chemical treatment options when requested by the customer under controlled conditions on the nursery, however, we believe that other methods can be just as effective with far reduced environmental impacts.


Chemical Control Options for Hylobius – Alba is one of the only nurseries in the UK to have a mechanical spray race for the application of insecticide.


We can offer a full plant spray or a reduced top-spray in conjunction with the use of WEENETS.

The accuracy allowed by the use of a mechanical spray machine means that the chemical remains effective for an extended period in the field, providing the following benefits:

  • Applied with maximum operator safety precautions
  • Every tree is treated
  • No need to carry out first season field inspections
  • Reduced need for top-up field sprays
  • Reduced health & safety risk associated with field spraying
  • Minimal environmental impact


Alba has recently partnered with ICL to provide MERIT to the forestry sector.

MERIT FOREST is the only systemic pesticide for the control of Hylobius – it acts by both contact and systemic action.

The active ingredient – Imidacloprid – disrupts the nervous system of insects, but not mammals. Treated trees will not affect non-target insects.

Considerable testing of the product has taken place, with impressive results. A pre-planting application helps to reduce the gnawing damage caused by Hylobius to conifers during the year of application and significantly reduces severe tree damage and death versus untreated plants or even Alpha Cypermethrin.


MERIT FOREST is very gentle to the treated plant and does not damage new growth. It is also comfortable to use and handle when planting, with no allergic reaction to the user.


Non-Chemical Control Options – we believe that a number of non-chemical options can be explored in order to reduce the impact of Hylobius.

GOOD SILVICULTURAL PRACTICE including the use of containerised plants that lend themselves to excellent early establishment can be beneficial in the fight against Hylobius. This allows plants to get above the invading weeds and to become strong and girthy enough to withstand weevil attack. The application of controlled release fertilisers at the time of planting also boosts early development. Alba provides a range of fertiliser products that cost 3.1p per plant and the benefits of containerised trees are discussed below.

Extended Planting Season

Planting can be carried out throughout the year, provided there is sufficient moisture in the ground.

Ease of Planting

Hand planting is speeded up as the planters do not have to contend with different sized root systems. The uniform nature of the root plugs also lend themselves to mechanical planting.

Excellent Early Establishment

Rapid early growth also enables the plant to get above the invading weeds – saving time and money on early crop care. This can be supplemented by the application of our specially developed fertiliser.


ALBACOTE is a controlled release tree fertiliser specifically developed and tested for UK forestry. It is a blend of NPK suitable for all types of trees and sites which will release slowly ensuring excellent establishment and growth and does not leach out under excessively waterlogged conditions.

10g is applied to each tree at planting and one 1.5kg bag will cover one full tray or bag of Alba stock.


WEENETS have been developed by Alba as a step towards reducing the amount of chemical used in the forest and to protect newly planted trees against  Pine Weevil.

The lightweight net is fitted to the tree at the nursery – each net is individually positioned around the root plug and lower part of the stem. Once planted out, the roots and side shoots can easily grow through the net and develop normally.

Planters have found the netted trees even easier to plant than regular stock.


WEEBARS can be used in conjunction with the WeeNet, the WeeBar plastic collar patented by Alba acts as a physical barrier to prevent weevil climbing the stem of the plant. Still in the trial phase, the collar is fitted at the nursery and incurs minimal additional costs per plant to the customer.


Contact our Sales team on 01620 825 058 or to discuss further.