- As in other Lasius species, there is a short period in spring with a reduced level of predatory activity. Nontheless, Lasius brunneus is better characterized as an aphid-tending species.
- The number of workers within the colony is unknown but likely to be very high. Probably > 10,000 in a mature colony.
- The location, both of the ants as well as the aphids, is under the bark, especially at the non-exploited zone of the cork. This renders extremely difficult, if not useless, any insecticide spray treatment.
- Biological control is not considered applicable. No natural enemies are currently known for Lasius brunneus.

The obvious option is, therefore, the use of delayed-effect baits This is currently the control treatment of choice for other pest ants, like the Argentine ant Linepithema humile (Mayr) whose societies are constituted of huge numbers of individuals and the feeding of whose workers is mainly liquid-based.
Preliminary field tests have been carried out. Baits with molasses as excipient were highly attractive. Consumption of baits was independent of the physical localization of baits within the tree (base of trunk, mid-height of the trunk, or where the trunk branches out).

The application of baits was carried out by means of darkened Eppendorf containers, additionally covered with opaque paper, to reduce the quantity of light inside the container. This was done to counter the light-avoiding escape reaction, characteristic of these ants. In the summer of 2004 we tested the effectiveness of baits based on clorpirifos (0.075%), which had been shown to be effective in laboratory. During 2005, new baits were used: a) an artificial diet with borax (6%) as active ingredient, b) commercial Blattanex® baits, and c) a new experimental bait without molasses and with clorpirifos (2%; Mylva CORP.). Finally, during 2006, different carriers were used using the boric acid as active matter (Mylva CORP.) at two different concentrations (3 or 5%). The higher boric acid concentrations gave only very partially satisfactory results.

Considering the location of the ants underneath the cork, we have to resort to indirect indicators in order to measure the effect of the treatments. The replacement of sawdust in the vertical slits by the workers of Lasius brunneus to protect themselves from the light, constitutes a direct and easy to measure variable. The process is as follows: 1) for every tree, the cumulative length (cm) of sawdust in the vertical slits and cracks is measured; 2) sawdust is then eliminated with a brush; 3) the bait treatment is administered; 4) the replacement of sawdust is checked every two weeks until hibernation begins; 5) a last measure is taken the following year in summer. The rationale assumption is that the lesser is the replacement of sawdust, the better is the state of the colony. For control trees, bait administration (step 3) is not applied.