In addition to the popular yellow boards, there are also blue insect catchers. Blue boards have proven particularly useful for thrips, where the blue glue traps are a useful tool for monitoring infestation.
You can use different adhesive panels to monitor and control insect infestation. Certain colors are more attractive to different insect species. For example, thrips (Thysanoptera), which are a common pest in greenhouses or on indoor plants, react particularly well to the color blue. Below you can find out how best to use the blue, sticky traps, how they work and what you have to consider when using blue boards.
What are blue panels?
Blue boards are adhesive boards that are primarily used for early infestation detection and pest monitoring. There are boards made of cardboard and plastic, but they are all coated with sticky insect glue. In the case of a severe pest infestation, it sometimes also makes sense to combine the use of blue panels with beneficial insects. In the case of a heavy infestation with thrips (Thysanoptera), you can combine the blue panels with predatory mites (Gamasina), for example. In principle, however, the color blue is enough to attract the insects, which then stick to the glue.
Tip: At first glance, thrips can easily be mistaken for fungus gnats. The latter can be recognized by their staggering flight and the fact that they are much more likely to fly to the color yellow than to the color blue. This is why they are easier to identify with yellow panels, such as our Plantura yellow panels, instead of blue panels. Control is then carried out with entomopathogenic nematodes such as our Plantura SF nematodes.
Use blue panels correctly
The blue glue boards are commercially available in different sizes. You can attach them in different ways: either you stick the blue boards directly into the ground, attach them to a stick or you hang the blue boards on a stickwire up. In any case, the panels should always be placed close to the infested or endangered plants.
Blue boards are hung between plants to identify and monitor infestation with specific insects. In principle, however, blue panels are not used for pest control, but only for infestation control.
Pest Control Blue Boards
The blue color of the panels primarily attracts insects from the order Thysanoptera, i.e. thrips. The panels work particularly well with Californian flower thrips (Frankliniella occidentalis).
, for example.
Trials show again and again that thrips in particular are attracted to the color blue. Since thrips also like to infest plants such as passionflower (Passiflora), whose flower is partly blue, the attractiveness of the color could provide an explanation. Insects are generally attracted to colors that signal to them, for example, that food is waiting for them.
When using it, however, it should be noted that such panels can only decimate an infestation, but are not sufficient for pest control. Some flies always escape the panels and are therefore able to reproduce further. Blue glue traps are primarily used to detect an infestation as early as possible so that countermeasures can be initiated quickly and more serious damage can be prevented. They are also good for monitoring combat success.
Blue signs as a danger for beneficial insects?
But if these panels attract insects, one can actually assume that not only unwanted animals but also beneficial ones are attracted and stick? Fortunately, the thrips is a typical greenhouse and living space pest and bees, bumblebees and Co. very rarely stray there, so you don't have to worry too much about using it there. In the field, on the other hand, it is more common for beneficial insects and even small birds to stick to the traps. So if you do want to use the panels outdoors at some point, you should think twice about it.
Make blue boards yourself
Who not toIf you want to go to the hardware store to get the blue adhesive boards, you can of course also make them yourself. Simply cut out pieces of the right size from blue construction paper and laminate them. In this way you can customize the blue panel according to your needs.
Then use a stapler to punch holes in the blue boards so that you can easily attach them later. Then the panels have to be made sticky. To do this, you can use a mixture of half a kilogram of sugar and half a liter of water. Boil this until it becomes a sticky mass. Spread this mass on the blue boards - and your self-made blue boards are ready.
Tip: It's easier if you already buy a ready-made insect glue that you can also paint on your colored boards.
You can of course also carry out experiments with the glue boards you have made yourself and try out different colors and combinations of several colours. The plaques can also be reused by simply scraping off the trapped insects with a spatula and applying a new layer of the sugar mixture.
There are not only blue boards, but also glue boards in other colors. Our Plantura yellow charts indicate, for example, an infestation with fungus gnats (Sciriadae), whiteflies (Aleyrodidae) or winged aphids (Aphidoidea). We have summarized more about the different types of glue boards or the use of yellow boards in two separate articles.