Common name: Mediterranean pine shoot beetle
Scientific name: Tomicus destruens
Order: Coleoptera
Affects: Pine forests of Pinus pinaster, P. halepensis, P. radiata and P. pinea
Main season: Autumn, Winter and Spring
The Tomicus genus consists of seven species of coleopterans from the subfamily Scolytinae (Curculionidae) that cause damage to species from the Pinus, Abies, Larix and Picea genera. They are distributed throughout much of the Palearctic region, having been introduced into North America in the 1990s.
Tomicus destruens is considered to be a primary or aggressive species, that is widely distributed in forests. This species attacks P. halepensis, P. pinaster, P. pinea and sometimes P. nigra.
Pinus halepensis affected by Tomicus destruens
T. destruens measures 3,5 - 4,5 mm long and has a black head and thorax. The elytrons are brown, just like the legs. Oviposition takes place in the maternal galleries, in incisions made by the female on both sides of the gallery. The eggs are white and approximately 0.5 mm in diameter.
Physical appearance of Tomicus destruens
The number of eggs laid by the females can vary between 60 and more than 200. The larva is apodous and curved. It is also white with a brown head. When the larvae hatch, they barely reach 1 mm in length, but in the 4th and final larval stage their length is equal to or slightly greater than that of the imagoes.
The pupa grows at the end of the larval galleries, inside the pupal chamber. They are found on the bark or between the bark and the wood. These pupae are whitish and already show the visible appendages of the imago.
T. destruens has two clearly different stages in its life: the first stage is under the bark of weak trees,where copulation, egg laying and development of the new generation take place. The second stage is in the branches of the crowns of healty pine trees , where the imagoes feed.
T. destruens begins to fly from mid-September until the maximum temperature is below 20 °C, which may also occur during short periods of time from December to February when it can fly. Between October and December, they lay the eggs of the first generation which will emerge in March.
When the maximum temperatures in February or March rise above 20°C again, reproductive flight also begins anew, producing the second generation of eggs being laid. This generation will then emerge in May or at the very latest, early June. Both generations are siblings because they come from the same parental generation.
Reproduction begins after finding a host tree through sense of smell (at long distance) and sight (at short distance). Once located, the females begin to bore a hole in the tree trunks and thick branches. Each male enters after each female and following copulation, stays behind the female getting rid of sawdust whilst she excavates the vertical and uniramous gallery. The female lays each egg individually, in small incisions on either side of the gallery and then blocks the hole to stop predators from getting to the eggs.
A pair of Tomicus destruens inside a subcortical gallery
A few days later the larvae are born and start to perforate galleries that are perpendicular to the maternal galleries, filling them with sawdust and excrements as they pass by to stop predators from entering. The larva goes through four stages, later changing into a pupa inside a small chamber underneath the tree bark, which can leave a mark in the wood. The dyspigmented preimagoes, remain for some time in the chamber, to later go outside through a hole that they perforate in the bark.
Small branches perforated by Tomicus destruens and blown down by the wind
After that, they fly to the crowns of the trees and insert themselves into the pith of dying branches, to feed on them and mature sexually. The imagoes remain in the tree crowns throughout summer, moving from one branch to another. The tips of the branches are very often severed, falling to the ground. The parent generation also needs to spend some time feeding on branches between the egg laying in Autumn and again in Spring.
The Tomicus produces two types of damage: in the subcortical galleries of the tree trunks and thick branches; and galleries in the branches of the crowns. Attack on the tree crowns is irrelevant, given that the trees they attack have enough vigour to regenerate the losses. On the other hand, attacks on the tree trunk are always fatal, because fungi are introduced through the maternal galleries and especially the larval galleries, causing degradation of the phloem surrounding the gallery. In addition, whilst the larvae feed, a mechanical destruction of the phloemic channels is produced.
They select trees or parts of the trunk, with bark that is not too thin or too thick. They do not tend to attack in replanted areas. The attacked trees are easily recognisable because of the volcanoes of yellow resin that surround the entrance holes. Sometimes trees can be found with rejected attacks, alive, but with volcanoes of resin.
Galleries and volcanoes of resin
They prefer to reproduce in trees that are in the early stages of deterioration, mainly due to lack of water, competition with other trees, damage by fire or mechanical damage. They behave like primary or aggressive species, capable of killing quite strong trees and do not usually attack previously attacked trees by other bark beetles (except for very rare cases, such as Pinus pinaster being attacked by Ips sexdentatus).
In the absence of occasional damage, such as fires or drought, the trees at most risk of attack are those that are found in poor, not very deep soil with hardly any rain and too many trees per hectare. Frequent attacks on very old trees (>80 years old) have also been detected, it is possibly linked to the trees aging. Another risk factor is the forest work involved in clearing and extracting trees. In some cases, attacks have been registered in healthy trees.
Particular attention must be paid to the periods of intense and prolonged drought, as they influence in Tomicus destruens not only attacking individual trees, but also large masses of forest. Between 1994 and 1996, nearly 40,000 hectares of pine forest were affected after a prolonged drought in the Region of Murcia.
Abandoned wood from forest work is the perfect material for Tomicus destruens to reproduce on, and once the population density has reached high levels, this species could become a real threat for other trees and forests. With regard to the pest situation, at first the dead trees appear to be alone or in small circular areas. The population of the insect grows rapidly and the outbreaks change into continuous patches, which are more extensive every time.
Visual diagnosis is based on the presence of volcanoes of yellow resin on the tree trunks and thick branches. Normally this symptom is detected after the crown suddenly turns yellow. By removing the bark, the presence of the species is confirmed. This discolouration is produced in advanced stages of infestation, when the parent and part of the offspring generation have abandoned the host.
This makes controlling the pest all the more difficult. By working solely on the part of the offspring population and practically nothing on the parental generation, the treatments for cutting down and debarking a tree are only partly effective. In very weak or cut down trees no volcanoes of resin form, so diagnosis can only be carried out by removing the bark on the trees and identifying the galleries.
There are two types of damage, with different methods of management.
EXTENSIVE DAMAGE, in forest areas. The following levels of damage have been suggested:
Grade 0: Stand with some dead trees, possibility of rejected attacks.
Grade 1: Stand with dispersed dead trees.
Grade 2: Stand with dead trees and some small dispersed circular areas.
Grade 3: Stand with clear evidence of large or many small circular areas tending to mass mortality.
Grade 4: Mass mortality.
LOCALISED DAMAGE in public areas, such as parks and gardens.
Grade 0: Some dead trees and rejected attacks on others.
Grade 1: Death of less than half of the trees.
Extended damage: Grade 1
Localised damage: Grade 2
Localised damage: Grade 2
Localised damage: Grade 2
In forests, 1 CROSSTRAP® MINI should be placed every 20 hectares and separated at least 1000 m from each other. For surfaces that are less than 20 hectares, at least one trap should be placed per stand or forest. The traps should be placed in areas with good visibility, such as forest borders, forest trails or firebreaks. Windy areas should be avoided, as the wind makes it more difficult for the insects to fly and could damage the traps. Detection traps should cover the environmental variability of the monitored forest.
As a rule, the traps should be placed and active between mid-September and mid-April. These periods could be shorter for the years that have a very warm early autumn and early spring.
Phenology of Tomicus destruens
For monitoring, wet captures are recommended as they allow for the precise identification of the captured insects. For this purpose, fill the collection cups with 10 ml of diluted propylene glycol (10 or 20%), or where appropriate, vehicle antifreeze may be used. This liquid is used for killing the captured insects, as well as preserving them, as long as it does not dissolve too much with the rainwater, in which case it should be replaced. It is recommended to collect the captures at least every 15 days.
Example of trap installation for the DETECTION AND MONITORING of Tomicus destruens, in a forest area of 1500 hectares, with 35 traps installed along forest trails and firebreaks and with a distance between traps of 1000 m.
In forests
To intensify monitoring, traps should be placed at a distance of 100 and 500 metres between each other, following forest trails, firebreaks and forest borders.
The density of traps can vary between 0,3 and 3 CROSSTRAP® MINI traps per hectare. They can also be installed inside forests, as long as they are not too dense. For exhaustive monitoring dry captures are recommended, using the collection cup with a stainless steel mesh base and a slippery product. This collection cup stops the bark beetles from escaping, as they cannot climb out due to the slippery product. Although, it allows the entrance and exit of the predator Thanasimus formicarius, who devours the captured insects. This minimises the impact of trapping useful fauna.
Example of trap installation for the EXHAUSTIVE MONITORING of Tomicus destruens, in a forest area of 1500 hectares, with 35 traps installed along forest trails and firebreaks and with a distance between traps of 500 m.
In parks, gardens and residential areas
Managing Tomicus in parks and gardens presents some peculiarities that differentiate it from controlling this pest in forest environments. The biggest risk of attack on ornamental trees is caused by mechanical damage. Attacks due to the destruction of roots that are more or less severe are very common. They are produced through excavation work surrounding the trees. In general, ornamental trees are not very susceptible to attacks by Tomicus, provided that they are maintained in the same conditions in which they grew in. Sometimes, putting in or removing irrigation systems in parks and gardens can provoke attacks from these insects.
Controlling Tomicus in these circumstances should be very effective, as the aim is to reduce tree mortality to zero. Therefore, the effort to trap these insects must be intensified as much as possible, so that 3 CROSSTRAP® MINI traps per hectare can be used. These traps must be checked weekly.
Example of trap placement for the control of Tomicus destruens, in an urban area with public parks containing pine trees (0,8 ha), with 4 traps installed in selected locations.
CROSSTRAP® MINI traps and ECONEX TOMICUS DESTRUENS 60 DAYS kairomone diffusers, which we will hang on the trap using one of the lateral holes on one of the PVC trap vanes.
ECONEX TOMICUS DESTRUENS 60 DAYS has two kairomonal attractant diffusers to attract male and female Tomicus destruens + 2 clips to hang the diffusers on the trap.
Diffuser A, contains 25 ml of a-pinene with a purity of 98%. The release rate is 0,3 grams per day at 20°C.
Diffuser B, contains 100 ml of ethanol with a purity of 96%. The release rate is 2 grams per day at 20°C.
The diffusers are in a blister pack, with a duration of 60 days and are individually packaged in aluminium sachets with a specification label. Once taken out of their packaging, the diffusers need no activation or opening, just placed correctly on the trap.
packaging and diffuser A
packaging and diffuser B
ECONEX TOMICUS DESTRUENS (60 days)
Kairomone diffusers for the attraction of both sexes of the species Tomicus destruens, with a duration of 60 days in normal field conditions.
Code: UIPHOVA250
ECONEX TOMICUS REPELLENT 120 DAYS
Repellent diffuser for Tomicus with a duration of 120 days.
It is a benzyl alcohol diffuser containing 100 ml of product. This product acts as a repellent of T. destruens. It has been shown to reduce captures of between 70% and 80% in traps baited with T. destruens attractants and with these diffusers compared to the same traps without this repellent.
Its recommended use is for the protection of individual trees at risk in parks, public or domestic gardens, as well as singular and monumental trees.
ECONEX TOMICUS REPELLENT 120 DAYS
Tomicus repellent diffuser with 120 days duration.
Code: UIPHOVA308
To optimise its efficiency, it is recommended to install a CROSSTRAP® MINI trap baited with the kairomonal attractant ECONEX TOMICUS DESTRUENS 60 DAYS, near the trees that need protecting. A minimum distance of 20 m must be kept between the trees and the trap, to ensure that the insects go to the trap and not to the trees that need protecting.
A diffuser must be installed every 4 linear metres of the tree trunk, until the appearance of the thin bark. The diffusers should be installed by nailing them to the knots or other areas of deadwood on the tree.
Diagram of ECONEX TOMICUS REPELLENT 120 DAYS diffusers being installed and protecting a tree about 20 m high.
Example of installing repellents and traps to protect individual trees against Tomicus destruens in gardens. The distance between the trap and the tree with repellents is 50 m.
The CROSSTRAP® MINI trap is a state-of-the-art forest trap that was developed in an R&D project (University of Murcia – ECONEX) with the aim of developing traps and attractants for forest insects.
The trap consists of a 33 cm diameter polypropylene lid with a central carabiner attached to a steel spring. Two reinforced PVC vanes are held in place by four steel springs in the lid's upper section. They are used as elements of dynamic suspension, acting as shock absorbers against the force of the wind exerted on the trap, preventing it from breaking in the forest. They are also attached at the bottom to a 30 cm diameter polypropylene funnel. The lower part of the funnel is fixed to the collection cup with screws.
The vanes, funnel and collection cup are treated with a slippery product that increases the number of captures considerably, preventing the insects from escaping.
The CROSSTRAP® MINI trap can last for up to 7 years due to its structure and highly resistant components. The unfolded trap measures 33 cm diameter x 100 cm high. Once folded, it is 33 cm diameter x 40 cm high, making it easier to transport.
CROSSTRAP® MINI WITH WET COLLECTION CUP (with slider)
CROSSTRAP® MINI WITH WET COLLECTION CUP is the latest generation in cross-vane traps to help capture forest pests.
Code: UIPFETA226
OMDF register number (Ministry of Agriculture of Spain): 153/2013
CROSSTRAP® MINI WITH DRY COLLECTION CUP (with slider)
CROSSTRAP® MINI WITH DRY COLLECTION CUP is the latest generation in cross-vane traps to help capture forest pests.
Code: UIPFETA204
OMDF register number (Ministry of Agriculture of Spain): 153/2013
The trap can be used with two types of collection cup: CROSSTRAP® WET COLLECTION CUP for wet captures and CROSSTRAP® DRY COLLECTION CUP for dry use or live captures.
The CROSSTRAP® WET COLLECTION CUP has a capacity of approximately 2 litres and a drainage system at the top that prevents it from filling with rainwater.
The CROSSTRAP® DRY COLLECTION CUP has the same capacity and measurements as the CROSSTRAP® WET COLLECTION CUP. It is provided with a stainless steel mesh at the bottom to drain away 100% of the rainwater and ease air circulation.
CROSSTRAP® WET COLLECTION CUP (with slider) 2 L
Collection cup for wet catches, located at the bottom of CROSSTRAP® traps.
Code: UIPFETA156
CROSSTRAP® DRY COLLECTION CUP (with slider)
Collection cup for dry use, or live catches, located at the bottom of CROSSTRAP® traps.
Code: UIPFETA157
CROSSTRAP® DRY COLLECTION CUP
View from below
In forests, the number of traps is determined by the area to be covered and by the network of roads, firebreaks or accessible forest edges. For exhaustive monitoring, trap densities of between 0,1 and 0,3 CROSSTRAP® MINI traps per hectare is recommended, separated between 100 and 500 linear metres, for which we recommend the use of a GPS during installation.
In parks, gardens, recreational areas, domestic outdoor gardening or small forest areas ( <5 ha ), trap densities can be greatly increased up to 3 CROSSTRAP® MINI traps per hectare.
In these locations, the death of just one tree is shocking enough to intensify trapping, so that as many insects as possible are captured.
The diffusers must be stored in their original packaging in a cool and dry place and separated from food and drinks.
To preserve the diffusers for long periods of time, it is recommended to keep them in the refrigerator at 4 o C in which case they will last for 2 years. Or they can be kept in the freezer at -20 o C for 4 years.
ECONEX TOMICUS DESTRUENS 60 DAYS
Corrugated cardboard box of 100 units.
Box size: 0.60 x 0.40 x 0.35 m (length x width x height).
Box weight: 23.5 kg.
No. of boxes per pallet: 20
Pallet size: 1.20 x 0.80 x 1.95 m (length x width x height).
Pallet weight: 477 kg.
Pack of 5 units
Box of 100 units
(20 packs x 5 units)
ECONEX TOMICUS REPELLENT 120 DAYS
Corrugated cardboard box of 200 units.
Box size: 0.60 x 0.40 x 0.35 m (length x width x height).
Box weight: 17.5 kg.
No. of boxes per pallet: 20
Pallet size: 1.20 x 0.80 x 1.95 m (length x width x height).
Pallet weight: 357 kg.
Pack of 10 units
Box of 200 units.
(20 packs x 10 units)
CROSSTRAP® MINI WITH WET COLLECTION CUP (with slider)
Corrugated cardboard box of 8 units.
Box size: 0.60 x 0.80 x 0.48 m (length x width x height).
Box weight: 11.30 kg.
No. of boxes per pallet: 8
Pallet size: 1.20 x 0.80 x 2.05 m (length x width x height).
Pallet weight: 100 kg.
Box of 8 units.
CROSSTRAP® MINI WITH DRY COLLECTION CUP (with slider)
Corrugated cardboard box of 8 units.
Box size: 0.60 x 0.80 x 0.48 m (length x width x height).
Box weight: 11.30 kg.
No. of boxes per pallet: 8
Pallet size: 1.20 x 0.80 x 2.05 m (length x width x height).
Pallet weight: 100 kg.
Box of 8 units.
ECONEX CATALOGUE OF PRODUCTS AND SERVICES FOR FOREST PESTS
Catalogue in PDF format with 94 pages. An essential reference book about the biological behaviours of the main forest insect populations. It also includes solutions from ECONEX to solve the problems caused by these insects through the use of traps and specific attractants.
Download the catalogue by clicking on the image.
ECONEX TOMICUS DESTRUENS 60 DAYS LEAFLET
The leaflet can be downloaded in PDF format by clicking on the image.
ECONEX LEARNING CENTER
ECONEX puts at your disposal the first open knowledge center that brings together everything necessary to implement pest biocontrol in your crops. We have developed different types of resources to share with you the knowledge we have acquired during our more than 38 years of experience. Each of them is designed to respond, in the best possible way, to different questions related to pheromones, attractants, repellents and insect traps.
To access ECONEX LEARNING CENTER click on the image.
SANIDAD AGRÍCOLA ECONEX, S.L. only guarantees the composition, formulation and content of the products, taking responsibility for the direct, immediate and exclusive damages caused in the composition, formulation and content of the products sold. SANIDAD AGRÍCOLA ECONEX, S.L. will not be held responsible for damages produced by factors beyond the company’s control that have either totally or partially contributed. For instance, the weather conditions, usage or mixing with other products, amongst others. In addition, SANIDAD AGRÍCOLA ECONEX, S.L. will provide recommendations and information supported by extensive and meticulous research and tests; which must be taken into account by the customer when using the products. The customer will be responsible for any damage caused, in whole or in part, for the total or partial non-observance of the instructions provided. Furthermore, the customer will be responsible for all that is referred to as the performance of the products; which comes from total or partial non-observance of the instructions and information provided by the company.