Fight boxwood pests: Zünsler & Co.

As robust as the boxwood may seem, it is usually not spared from pests. We show how to recognize the symptoms and fight the pests.

When you look at the boxwood (boxy) thinks, when it comes to pests, the box tree moth usually comes to mind first. Unfortunately, he's not the only one who likes to attack our book. We present the various pests and show how to combat them successfully.

Not only diseases affect the boxwood, but also pests can attack it. Small animals eat their fill of our plants and usually leave a sad picture behind. What you can do and who you are actually dealing with is explained below.

box tree moth

One reason for box trees being eaten away is often the caterpillars of the box tree moth (Cydalima perspectalis), originally from East Asia. In this special article, we will tell you how you can identify this malware with certainty box tree moth.

Box tree moth: symptoms

The voracious caterpillars can be found on boxwood bushes from mid-March. The butterflies, on the other hand, are rather inconspicuous with their white wings with brown tips, but their offspring are only too happy to attack our boxwood. The green caterpillars, which are up to 5 cm long, have eye-catching black dots and a black head capsule. First they eat windows in the box leaves and over time the caterpillars eat all the leaves and even shoots. Since they start from the inside of the bush, the infestation is not initially noticeable. The caterpillars later become entangled and your beloved boxwood is finally covered with a spider web-like web.

Tip: Pheromone traps like that Plantura borer trap serve for the early detection of a borer infestation. In this way, you can quickly take active action against the pest.

Combat box tree moths

If you take a close look at your boxwood regularly and also take a look inside the bush throw, you will hopefully recognize the infestation early on, because then combating it is still easy possible. A biological spray like ours is suitable for this Plantura Zünslerfrei XenTari^® outstanding. There have also been sightings of native birds eating the bitter caterpillars, but this is usually not enough.

In addition to biological sprays, you can also collect them by hand or spray the caterpillars with a spray gun Try water jet, but always use gloves to be on the safe side, as the caterpillars release poisons from the boxwood take up. The extent to which these toxins are released by caterpillars is not yet known. Therefore, you should Dispose of the box tree moth larvae better exercise caution. More about the successful Control of the box tree moth you can also read here.

Shoot tip mite on boxwood

Twisted shoots and leaves are attacked by the shoot tip mite (Eriophyes canestrinii) which belongs to the gall mite family. Unlike other gall mites, this one does not cause galls and growths, but rather deformities.

Shoot tip mites: symptoms

The shoot tip mites cause deformation of the boxwood shoots by sucking sap out of the plant cells. This stuns the leaves and shoots of the boxwood, leaving the leaves small, thin, and growing twisted.

Combat shoot tip mites

The shoot tip mites do not pose a serious threat to the box, but are more of an optical problem. If you trim your plant regularly, you shouldn't have much of a problem with these mites. If you find individual shoots with the shoot tip mites, you can also remove them in a targeted manner.

A boxwood variety that is particularly susceptible to these gall mites is 'Green Mountain', but there are also varieties that less sensitive to these mites - these include 'Herrenhausen', 'Faulkner', 'Hollandia' or 'Handsworthiansis'.

Spider mites on the box

Since the year 2000, a relatively new pest that originally comes from North America has been found on box trees in Germany: the box tree spider mite (Eurytetranychus buxi).

Spider mites: symptoms

You can just about spot these little spider mites on the leaves with your eyes, as they are only 0.35 to 0.48 mm in size. The boxwood spider mite can reproduce extremely quickly and form up to eight generations per year. The damage caused by these spider mites can be recognized by bright dots and short lines that look like a comma. This damage is caused by the animals sucking on the plant cells. If the infestation is very severe, the entire leaves will turn light and in the worst case the box tree will drop them completely. The mites can multiply best on box trees when they are sunny and warm locations - but they also occur in shady places, they only multiply there slower.

Fight spider mites

These mites are liked by beneficial insects like lacewings (Chrysopidae) or ladybugs (Coccinellidaei) eaten and also washed from the leaves by summer thunderstorms and thus clearly decimated. However, if they are threatened with a severe infestation, you can use oil-based sprays in autumn or spring against the hibernating spider mite eggs. Unfortunately, no particular varietal differences with regard to this pest could be found in the box varieties.

Boxwood leaf flea on boxwood

Another sucking pest that can affect boxwood is the boxwood flea (Psylla buxi). The larvae and adults are greenish in color and the larvae form a white waxy wool under which they hide.

Boxwood flea: symptoms

But how does the infestation of leaf fleas on boxwood show up? The fleas suck on the leaves, excrete sticky honeydew and black sooty mold fungi then settle on it. In addition, the larvae form their white waxy wool coat and thus protect themselves from enemies and from drying out. Fleas sucking on the leaves cause them to become spoon-shaped. The leaf spacings remain rather short and the shoot tips then resemble small heads of cabbage.

Combat boxwood flea

The leaf flea usually does not bother the box tree much and is also eaten by beneficial insects such as spiders, parasitic wasps or lacewings. Removing affected shoot tips is helpful in combating it. However, there were noticeable differences between the varieties, because 'Blauer Heinz', 'Elegantissima', 'Angustifolia' and 'Herrenhausen' showed relatively few symptoms, whereas the varieties 'Pyramidalis', 'Green Mound' or 'Graham Blandy' showed very strong ones exhibited.

Scale insects on Buchs

Especially with ornamental trees, you often have to deal with scale insects or mealybugs. With the boxwood one is particularly often with the comma scale insect (Lepidosaphes ulmi), which also occurs on fruit trees or rose bushes.

Scale insects: symptoms

The comma scale insect is about 2 to 3 mm long and grey-brown in colour. In contrast to other scale insect species, this species forms neither honeydew nor sooty mold, but the sucking activities of the comma aphids impair the growth of the boxwood. In the case of a very severe infestation, it loses its leaves and entire shoots can also die off. Due to the shedding of the leaves, these symptoms are quickly confused with those of boxwood leaf fall, but here you can easily see the lice sitting on the shoots.

fight scale insects

Since the lice cannot spread very quickly on the boxwood, often only individual branches are affected. These can easily be removed by cutting back. However, if the infestation is very large and cutting back is no longer effective, you can Treat the plant with an oily spray spray shortly after the lice hatch in May or June. Be careful not to act too late, however, as once the lice's shields harden, they are no longer very susceptible to treatment.

Boxwood gall midge on Buchs

Particularly in Central Europe, the boxwood gall midge (Monarthropalpus flavus) to fight and this little insect can do a lot of damage.

Boxwood midge: symptoms

Approximately 30 eggs are laid directly into the leaves per female that dies after oviposition. Small larvae then develop from these eggs, which eat tunnels in the boxwood leaves. These burrows, also known as mines, are easy to miss early in the infestation as they only appear as bright spots on the leaves. Later in the summer, the tissue then thickens and light brown spots appear on the upper side of the leaf, which are not very clearly demarcated from the healthy tissue. Galls form on the underside of the leaf, in which the orange larvae are then located, and leaf shedding can also occur. Exactly these galls with the larvae in them are a good distinguishing feature to the fungus of the box tree leaf fall.

Combat boxwood midge

Normally, the gall midges tend to infest older plants and this usually does not cause much damage. However, pruning measures can reduce the infestation pressure and, in the case of a very severe infestation, you can fight the larvae after hatching with insecticides such as Calipso. Here, too, a difference can be seen in the different varieties, since 'Handsworthiensis', 'Angustifolia', 'Herrenhausen', 'Faulkner', 'Rotundifolia' and 'Suffruticosa' less of the boxwood midge to be plagued. On the other hand, the 'Green Mound' variety from Canada is particularly badly attacked by this gall midge.

A brief summary of important boxwood pests

• box tree moth (Cydalima perspectalis)
• shoot tip mite (Eriophyes canestrinii)
• boxwood spider mite (Eurytetranychus buxi)
• boxwood flea (Psylla buxi)
• scale insects (Lepidosaphes ulmi)
• boxwood midge (Monarthropalpus flavus)

Boxwood damage: Frost damage, sunburn and Co.

But not only pests and pathogens can affect your beloved evergreen boxwood. Environmental conditions can also be responsible for damage and the loss of lush greenery. These are so-called abiotic causes of damage, since they are not caused by living organisms. The following abiotic damage can occur on boxwood:

• Frostbite and frost damage to foliage and roots
• frost drought
• broken snow
• sunburn
• salt damage

How you such Boxwood damage due to environmental influences You can find out what you can do to limit the damage and what you should do to limit the damage in our special article.

Everything you about boxwood diseases should know and how to fight them, we will show you here.