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For over 25 yearswe develop and manufacture "open" mobilemicrowave ovens. You will be demanding in bothIndustry for special applicationsas well as inhousehold areato theDrying of damp walls and floors and non-toxic pest controlof wood destroyinginsectsandmushroomsincluding dry rot used. With this experience, we have now succeeded in creating a low-cost series for environmentally friendly wood pest control for both pest controllers and those affected who want to solve their problem through self-application and to maintain their values. So you don't just get "Made in Germany" but also the quality seal "Blue Angel" from the Federal Environment Agency according to UZ57a.

Fritz Kohler

Microwave wood pest control - contract or do it yourself?

Above all, this includes a comprehensive remediation concept that not only diagnoses the infestation and the optimal one
control method, but also clarifies the cause of the infestation and takes preventive measures
prevention of re-infestation. Such a qualified restructuring concept requires in-depth specialist knowledge
Biology of the wood and in particular many years of experience. You should not expect this expertise from us,
because we, as developers and equipment manufacturers, will continue to deal more with microwave technology in the future
than with wood and building protection. A wood protection expert can draw up this renovation concept for you. But the
costs money that many do not want to spend. We often hear "only one beam is affected". Out of
experience, we can only recommend consulting such a specialist advisor. But please make sure that
You then also appoint a genuinely independent appraiser. Experts often have executives as well
Companies "in the background" - owned by your own wife or a "good friend". Then the
Independence is already gone, because the recommended actions are often not technically sensible and
cost-effective arguments are selected, but rather for the maximum turnover of the executing company
should lead. From our experience, there are only about half a dozen qualified and really in Germany
independent wood protection experts. One of these described a few biological connections to us,
which we would be happy to give you. See section “Biological Facts About
Wood Pest Control”. If you do not want to invest these consulting costs, you must yourself
get smarter: Among other things, you should know the type of wood pest. You can do this with the help of
Internets quite inexpensive also record yourself. This is relatively unimportant for the microwave application because
most die off with the key values of DIN 68800. But there is also the famous exception, see
Device operating instructions and insect table.
The next step is to determine the infestation - qualitatively and quantitatively. There will be z. B. in museum villages,
who are also struggling with these problems, infested beams are taped with special glue and packing paper in order
then count the exit holes in the next excursion season. In modern German this is called monitoring. So is
a quantitative statement is possible after a few years – if you have that long and/or not by then
whole beam is eaten away. The most widespread detection of infestation consists in the feeding meal under an exit hole
or gnawing sounds. But beware: this is evidence of an infestation, but if you don't hear anything and no
Finding drill dust does not mean that there is no infestation. So it's not easy, if not impossible
locate the affected area. Some detailed information:
The microwave device(s) must be directly in front of the beams /
Objects are aligned and pushed further after the heating phase. The treatment time – at
"normal" beams (approx. 12 - 20 cm) "over the thumb" approx. 1 - 2 hours/m., also depending on the type of wood, installation position
and ambient temperature.
On average, microwave treatment costs about 4 to 10 times that through a contractor
self-application. The difference lies primarily in the service or personnel costs and the
Tax savings, since you do not (yet) have to pay any taxes for your own service. But an executive company
the safety margins (2.5 m beyond the infested area) will also tend to be higher, so be it
warranty reasons or sales considerations.
Since the introduction of the low-cost series, the number of self-users has increased and brought
other advantages too: while the professional pest controller ensures success
owes control, self-users can also be responsible for lower security surcharges. That's how some go
Those affected do not take the path of extensive infestation analysis but e.g. B. in the case of a house borer infestation only after yours
Hearing because they feel primarily bothered by the gnawing noises and fight only the identifiable one
Area with a low neighborhood allowance (e.g. 0.5 m). Although this does not guarantee the entire infestation
is fought (see article "Worth knowing about the spread of wood pests"), but should still be there later
If an infestation occurs elsewhere, you can combat this infestation without additional equipment costs since you
already have the equipment to do so.

Worth knowing about the spread of wood pests in wood

Control of wood pests in wood
By Joachim Wießner, expert for wood protection,

Wood is a natural building material and is therefore subject to the cycle of nature. If the natural
The decomposition process with the wood is over, then humus is present. Practically every type of wood and for every one
installation situation, there are suitable harmful organisms that can damage the wood.
The most common insects found in our buildings are the common woodcarid beetle, the spotted one
Rodent beetle and the house longhorn. The house longhorn requires mostly dry wood, with wood moisture content of up to 8% for
are suitable for development. The common woodworm beetle needs at least 16% wood moisture, that
A wood moisture content of approx. 35% is ideal for him. The situation is similar with the spotted nail beetle, the
however, relies on fungus-infested wood for laying eggs.
Due to the renunciation of wood preservatives, infestations by house longhorns have increased again in recent years
living quarters. There the gnawing noise of the larvae disturbs. In order to carry out safe combat,
it is necessary to know the way of life of the house goat.
The house borer infests the wood by the female house borer depositing the eggs in cracks in the wood. have these cracks
a width of 0.2 – 0.5 mm. The depth should be between 1.2 and 1.8 cm, at least that's how long the tube is
of the female house goat.
A minimum of 30 eggs and a maximum of 60 eggs are laid per clutch. Therefore it is technically impossible that in a bar
only a single larva is present.
The house longhorn feeds in the nutritious sapwood. The sapwood can be found on the outside of the component. the
Longhorn larvae can hardly get past the core of pine wood, which means that the infestation is always there
only in the splint area. This also applies to the wood species larch. It is definitely the case with spruce and fir wood
conceivable that the house longhorn also penetrates the mature wood. So if only on the edges of the beam the nutritious
sapwood, the house borer larva is trapped in this timber zone.
In general, however, it always remains directly below the surface of the wood. If the house borer larva has eaten enough, then it has
the so-called pupation weight is reached. It is about 0.25 g per larva. Then the longhorn needs an impulse
from cold to warm, as can be found in normal wooden constructions in spring. This
Pupation impulse causes the house borer larvae to gnaw their way just under the wood surface and there
leaves only a paper-thin layer of wood exposed to the outside air. It forms a pupal cradle and the pupation
takes about 6 weeks. The finished insect then hatches. It bites through the wooden surface and flies out.
Thus, these oval holes are exit holes, not entry holes. The exit holes
indicate that the house longhorn (larva) lived there. He (she) is gone now.
The house goat has natural enemies. One enemy is the woodpecker. If the woodpecker hears the feeding noises of the longhorn larva,
then it prys open the wooden surface with its strong beak and eats the larva. So if one
Longhorn larvae hear a knock on the wood and stop eating. This feeding break can last for several days.
In addition, the bucks sit in different wood depths (in the millimeter range) and in different
tree ring widths. Depending on the nature of the wood here, there is a more or less strong one
Soundboard that amplifies the feeding sounds of this insect. To put it bluntly, it is
Main noisemaker gone, you only hear the other larvae gnawing.
The house longhorn overcomes several meters in the wood in its life. If e.g. B. on a 10 m long rafter
Longhorn larva inserted at one end, it can be stated that after 3 - 5 years the longhorn larva also
may have overcome this 10 m. This can also be deduced from the feeding speed, which the
house borer larvae z. B. present in sample blocks. They are quite capable of growing 1-2 cm im
put back pine sapwood.
In addition, the house borer larva has an unpleasant quality. It can move from one component to the next
gnaw on This usually happens when the components are pressed against each other. Even
Glued laminated trusses are no exception.
In order to combat the house longhorn effectively, precise knowledge of the spread of the house longhorn is necessary.
But that is not so easy to determine. Exit holes only indicate where he has been. Are exit holes
there, insects have hatched. Usually about 50% males and 50% females hatch in the insects.
There is therefore a high degree of certainty that the insects will mate and thus lay eggs again.
Since the house longhorn is now increasingly appearing in living spaces again, it has gone through this pupation impulse
not the temperature change. In this case, the longhorn hatches when the longhorn larva
has reached the appropriate pupation weight. This is practically all year round. That also makes it difficult
the control of the house goat.
If you don't observe exactly when which exit holes were created where, you won't get an overview
about how far the house goats are spread and ultimately also where the active infestation is located.
The rate of development in the wood is also not always uniform. Thus is confirmed to the house goat,
that normal development in fresh timber takes 3-5 years. If you convert that into arithmetic, fly
every year after 15 years at the latest.
It therefore makes no sense for combating with the microwave to only selectively irradiate the wood. So
simply fighting longhorns from afar looks the more difficult it becomes
Assessing a fight if you are familiar with the house longhorn.
The situation is similar with the common nail beetle. Also known as anobium or woodworm
Wood pest needs wetter wood for its development. A typical distribution area is z. e.g. churches,
Garages, trusses, barns, stables and general storerooms that are not heated. That also includes
The woodworm has a number of preferences. It particularly likes to attack oak sapwood. He generally eats inside
wood, i.e. not below the surface. This is because within a wooden component in the geographic
The smallest humidity fluctuations occur at the center. The woodworm prefers this, as does the spotted one
nail beetle. The development time of these insects is given as 3 - 5 years. Here too must be taken into account
that the nutrient content of the wood plays a role, but also the development temperatures. At higher
The woodworm can develop faster at higher temperatures, the development time is around 3 years.
The woodworm has an unpleasant property. He slips out of his own old exit holes. So are
There are black exit holes, but that doesn't mean that the infestation is gone. In addition, he throws
Contrary to the information in the specialist literature, woodworm does not emit any feeding dust. So has a carpenter for years
Observation of an infested piece of furniture found that the woodworms hatched practically no
Eject feeding meal, but the subsequent pest, the blue fur beetle, is mainly responsible for the fact that these
Piles of scavenged dust are formed.
Conversely, this means that you cannot tell by looking at the wood whether there is an active infestation
is present if there is no meal. But if there is scavenger hunt, then at least it is certain that the natural ones
Enemies of the woodworm are present. These natural enemies can multiply all the more, like larvae
from woodworm are present. With that, you can definitely go back based on the found piles of meal
conclude that the woodworm is actively present.
If the wood is now only selectively heated with the microwave, where the piles of sawdust are, then
ultimately only the blue fur beetle is fought there. The actual spread of the woodworm is in none
way covered with it. Again, it only makes sense to irradiate the entire wood. Since the infestation but in the middle
of the component, pitting noises can hardly be heard with larger cross-sections.
The pied beetle relies on fungus-infested wood. It comes from nature for oak heartwood
Intended for fungal attack, but also attacks coniferous wood with fungal attack.
Once the larvae have grown, they can move up to 2.50 m away from the fungal infestation in healthy wood
drill in To put it in practical terms: If the foot area of a truss post is infested by the
spotted beetles, not only the foot area has to be cleaned with the microwave, but starting from there to
Fighting can be carried out 2.50 m above the last exit hole. Usually that means that
entire component is to be treated in the framework.
If this treatment is not carried out over the entire length, then insect larvae can survive. Through
the heat treatment has not changed the wood. The fungus-infested wood remains. The insect larvae don't care
whether the fungus is still alive or has died.
This means that the larvae are given their basic food again if moisture continues to enter and also a
new flight is possible. This is where another aspect of the heat treatment comes into play. through the heat
no preventive protection is created in the wood.
This means that the wood will continue to retain its physical properties if the general conditions remain the same
and thus a new infestation is possible again.
Sufficient experience is required here, based on the external conditions for re-infestation
shut down. Otherwise, the heat treatment must be used as a recurring building maintenance measure
be considered.
In the case of the gnawing beetles, there is also the fact that flour that is not always freshly trickled out by wood pests or their
natural enemies. If wood e.g. B. dries it changes its volume. Due to the change in volume
loosened residues of meal that had become lodged in the feeding tunnels. If there are vibrations in the area, e.g. B.
if a heavy lorry drives past the house on the street, the meal can trickle out. Also
enough experience is needed here to judge such a leak. Monitoring systems are then often used
used, which make it possible to switch between active infestation and spilling meal by shaking
Therefore, before heat treatment of the wood is carried out, it makes sense to find out more about the pests
inform and check on site how large the spread of the pests can be. It therefore makes sense to opt for
seek expert help in assessing such an infestation. On request I can provide you with appropriate
addresses help.

The house longhorn beetle

The house longhorn (often popularly known as wood tick) is a wood-damaging insect whose main task is to ultimately destroy the coniferous wood, which is no longer used in nature to generate oxygen, in such a way that it is returned to the natural cycle as humus in its final state. Similar to the woodworm, the longhorn also has a very specific infestation scheme. It is not the house longhorn beetle that is harmful, but the house longhorn larva.

The development cycle of wood-damaging insects, i.e. wood beetles and longhorn beetles, consists of laying eggs in the wood. Egg larvae develop from the eggs. The egg larvae gnaw their way into the wood. In the house longhorn they eat the sapwood of softwood. If the larvae weigh more than 250 mg, they pupate. The beetle hatches from the pupa. The beetle does not eat wood, but only has the task of providing for offspring. Then the cycle begins again.

For a long time, how the long-horned goat finds the wood was a topic that was fraught with many questions. After drying softwood (natural drying takes about 1 year), terpenes and their oxidation products are released from the wood. This smells the house goat man. Entomologists say that the smell can be detected up to 1 km away.

The male longhorn flies to the wood and uses its feeding tools to check whether the surface of the wood is suitable for the larvae to develop in it. This "taste test" shows e.g. B. superficially existing wood preservatives. If the wooden surface is suitable, then the male longhorn emits a scent mark. The house goat females follow this scent mark and mate.

This distinguishes the house longhorn from all other wood-destroying insects, in which the females make the decision as to which wood is used to lay their eggs. That's what Dr. Plarre from BAM in Berlin found out about 10 years ago.

The females then look for narrow cracks 0.2-05 mm wide on the surface of the wood in order to lay the eggs in these cracks with their laying tube. The cracks must therefore be so narrow that the eggs emerging from the laying tube are immediately held by the walls. After laying the eggs, the female dies, the male dies about two weeks after mating.

The larvae develop from the egg larvae. These egg larvae must be able to gnaw their way out of the egg shell and into the wood. Since the crack is very narrow, they can accordingly wedge themselves in this crack in order to apply the necessary force to gnaw into the wood. At this point at the latest, the destruction of the sapwood in the coniferous wood (wood erosion) begins.

The house longhorn larvae also take up proteins in the wood, among other things. The age of the coniferous wood does not play a major role. In the case of sticks from the 13th century, the BAM in Berlin found that the larvae used feed completely normally and show a completely normal increase in weight.

However, the development there is no longer quite as rapid as in completely fresh coniferous wood. while e.g. For example, in pine sapwood that has been felled for about 2 years, the longhorn larvae pupate within 2-3 years, in old spruce wood they may survive for 10-15 years until they have reached the pupation weight.

Pupation weight is ultimately the key to allowing the larva to pupate. To do this, it usually also needs a stimulus, which consists in the fact that after the cold winter, spring is slowly arriving and the wood is getting warmer. Then the larva eats under the surface of the wood, leaving a paper-thin skin. She then eats a pupa cradle that is free of meal meal.

This is where the finished beetle develops. This takes about six weeks. The beetle then bites through the thin layer of wood to get out. So there is an oval hole in the wood that is about 6-8mm long and 4-6mm wide. After hatching, the longhorn flies away. The house longhorn beetle no longer eats wood, but instead looks for a mate to reproduce. The cycle is then closed.

The body is bulging so that the house borer larvae can move in the wood. The house borer larva eats the wood and regularly turns around and pushes the meal to the rear. When eating, it produces barrel-shaped droppings, also known as droppings. This dung does not decay through aging, so even in centuries-old wood, these dung rolls can still be used to determine whether the house longhorn (or other longhorn beetle) had lived in that wood.

Females lay up to 350 eggs, with clutches of 50-60 eggs being common. Wood with a wood moisture content of more than 8% is accepted for laying eggs. It is therefore also possible that even dried wood can be infested by the house longhorn.

The house longhorn larva loves warmth. It likes to look for warmer places on the roof, i.e. the south side of the roof surface, around the chimney, skylight etc.. As the larva grows through feeding on the wood, it gets bigger and bigger and therefore has to shed its skin regularly.

It is important that the house longhorn larva is very shy of light when eating. It will not eat any openings in the wood surface. Therefore, in the case of an active infestation by house longhorn larvae, no meal is pressed outwards. The infestation can only be seen after the hatching of the first generation at the exit holes.

The house borer infestation is always a welcome pest for a quick deal. For this reason, DIN 68 800 Part 3, which regulates the control of wood pests, first requires that living infestation be proven. Live infestation can be detected by e.g. B. exit holes are marked and then checked at regular intervals of one year whether there are new exit holes.

It is easier if the gnawing sounds can be heard. The fine scratching in the wood can be heard especially on warm evenings in late summer. Then it is certain that there is a living infestation and it can be combated.

It is repeatedly claimed by certain circles that the house goat is threatened with extinction. This is a misconception. Since fewer and fewer wood preservatives have been used in practice for preventive protection, the number of houses infested with house longhorn has increased. The careless handling of unprotected wooden surfaces in the great outdoors also offers the male longhorned goat ideal egg-laying sites.

But even in living rooms, it is not uncommon for the house longhorn to use exposed ceiling beams to lay eggs. Of course, that devalues a property.

The longhorn beetles are cold-blooded. This means that they are only able to fly above a certain temperature. Before that, they can only crawl. The departure temperature is around 23 °C. Therefore, the infestation of wood only takes place when the temperature of 23 °C has been exceeded for a longer period of time. That is from May to August. By the end of September at the latest there will be no more living billy goats. In this respect, if building habits change and the house is set up in the fall, preventive wood preservatives could be dispensed with if the wood in the building itself that could be attacked is clad.

However, this natural preventive protection contradicts today's building habits. Therefore, the house goat will always accompany people when building a house.

insect table

Schädlingsbekämpfung Mikrowelle
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