Caterpillars and Bugs on Roses: Spotting 16 Common Pests

Rose pests have the property that they are often difficult to recognize, because only a few of the voracious pests are of an impressive size. In addition, they differ only slightly in appearance. Therefore, recognizing the damage pattern often leads to the goal more easily. Because not every pest immediately leads to total failure or has to be fought with full force.

Who is harmful?

Rose pests are mostly flying insects. However, it should be noted that the adult insects, whether beetles or moths, are often not the actual pests, but rather their offspring, because the plants serve them as nutrition in the nursery. However, danger lurks on two sides. On the one hand by the offspring, which will be sexually mature in the following year at the latest, and by the adult insects that have chosen the plants as hosts for the offspring. Therefore, it is advisable to pay attention to both generations, to take preventive measures so that egg laying does not occur in the first place. Natural predators usually help best with this form of defence, as they ensure a natural balance in the garden.

Occurrence of the rose pests

The distribution of the various pests varies. Some appear nationwide, some only regionally. Overall, however, it can be stated that the pests are spreading geographically, not least due to the rising temperatures. According to the calendar, rose pests can be expected from spring. Since some of the rose pests also develop two or more generations per year, the danger can extend into autumn (September, October). You should therefore regularly check the roses for pest infestation until autumn, especially if this is not the first infestation.

cutting tool and disposal

With many rose pests, it is often sufficient if they are removed mechanically or if the affected parts of the plant are cut off. However, you should not dispose of them in the compost, because some offspring continue to develop splendidly there. It is better if you dispose of the waste in the household waste. In order to rule out the risk of transmission as far as possible, you should always ensure that the cutting tool is clean. It is therefore advisable to clean it, even between cutting, even if it seems tedious at first glance.

Deformations, leaf damage, galls

This group includes pests that you can identify by the external appearance of roses. In this way, the rose petals are eaten or the buds are damaged. Galls are often referred to as nodules because they grow in place of buds or on leaves or stems. sit shoots They serve as nurseries for some insects, i.e. the offspring are located inside the galls in more or fewer chambers.

Leafcutter Bees (Megachile)

Damage:

• Circular to oval feeding marks on the leaf edges
• local leaf loss
• Material cut off is used by the bees to create nesting sites
• Breeding places not at the rose (possible up to a distance of 100 meters)
• Nourishing the offspring from the rose

Measures:

• Damage rather small
• No action necessary

A notice: If you do not take action here, you will help these wild bees, which look similar to the normal honey bee, but do not form colonies.

Common rose gall wasp (Diplolepis rosae)

The common rose gall wasp belongs to the gall wasp family (Cynipidae).

Damage:

• Gallen, also called rose apple, bedeguare or sleeping apple
• spherical swellings instead of rosebuds at the middle or upper end of the shoot
• five to ten centimeters in diameter
• many colored mossy to hairy outgrowths (greenish, yellowish reddish)
• Rose gall chambers are used for larval development

Measure:

• remove with one cut

Common rose chafer (Cetonia aurata)

Synonyms: Rose Beetle, Golden Shiny Rose Beetle

Damage:

• flower feeding

A notice: This beetle species is protected in Germany. However, it doesn't do much damage either.

Gold macaw (Euproctis chrysorrhoea)

Damage:

• Eggs are laid on the underside of the leaves
• around 250 pieces per clutch
• elongated scrim: 2 x 0.5 centimeters
• covered with golden yellow after-wool
• Rather inconspicuous
• found in the outer, upper crown area
• Caterpillars hatch after two weeks
• scraping damage on the upper side of the leaf
• give off threads
• together with other leaves: fist-sized nest
• after hibernation: feeding on buds, then leaves (defoliation)
• Pupation in June on leaf or stem

Measures:

• remove the webs in winter

Lesser rose chafer (Phyllopertha horticola)

Synonyms: Garden chafer, June beetle

Damage:

• Eating marks on leaves and rose petals
• late May to late June

Measures:

• collect bugs

Rose leaf gall midge (Wachtliella rosarum)

Damage:

• Leaflets of the rose folded along the midrib
• Galls initially greenish, later reddish-brownish
• on upper shoots or to find leaf layers
• inside: legless larvae of the rose leaf gall midge
• Oviposition in late spring on the central axis of the leaves

Measures:

• collecting the leaves

Rose leaf scroll wasp (Blennocampa phyllocolpa or Blennocampa pusilla)

leaf scroll wasps (Blennocampinae) belong to the sawfly family (Tenthredinidae). They are often associated with the roller wasps (Tiphiidae) confused by name, but there is no relationship between the Hymenoptera. Within the real sawflies there are different subfamilies, such as the leaf scroll wasps (Blennocampinae).

Damage:

• curled leaves
• by the laying of eggs by the female rosette scroll wasp on the edges of the leaves
• Larvae hatching: between April and June

Measures:

• Remove affected leaves immediately and dispose of with household waste

Rose blossom weevil (Mecorhis ungarica)

Synonyms: Bud picker, raspberry blossom picker

Damage:

• cut stem below half of the bud
• Females lay an egg in each bud
• Larvae feed on the inside of the bud
• new generation in June and July: still feeding on the leaves

Measures:

• drooping or Burn fallen buds or safely dispose of them in the household waste

Rose brush wasp (Arge rosae; argue ochropus)

Synonyms: Yellow bow tie, sewing bow tie

Damage:

• Oviposition at the top of the rose shoots
• 15-20 pieces in a row
• seam-like structure (name!)
• tan spots
• twisting shoots
• Larvae eat leaves (from leaf margin to midrib)

Measures:

• Remove larvae mechanically
• Cut off shoot tips with clutches

Rose flea beetle (Luperomorpha xanthodera)

Synonyms: flea beetle

Damage:

• adult beetles: pollen and nectar, feeding on flowers
• Larvae in the root system of the plants (suspected)

Measures:

• usually no control necessary

Arrow owl (Acronica psi; Arconycta psi; Apatele psi)

Damage:

• leaf feeding of the caterpillars

Measures:

• mechanical removal of the caterpillars

Black sawfly (Endelomyia aethiops; Caliora aethiops)

The plant wasp also belongs to the real sawflies, more precisely to the subfamily of the Heterarthrinae.

Synonyms: rose sawfly

Damage:

• Scraping marks on the leaf edges and leaf tops
• "holes" in the rose petals
• Leaves are "skeletonized"
• Infestation recognizable from May or June
• Roses that are particularly endangered: Field rose (Rosa arvensis), Dog rose (Rosa canina)

Measures:

• Remove affected leaves and shoots immediately and dispose of with household waste

leaf miner

Under the so-called Miner damage is to be understood as a form of damage that is inside the shoots. Because in this case the offspring does not eat externally, but "drills" feeding tunnels into the shoots. This so-called Mining tunnels are not so easy to recognize from the outside. But often the entry point is a good indicator of the infestation.

Downward Rose Shoot Borer (Ardis brunniventis)

damage picture:

• short mining tunnels at the shoot tip
• up to 5 centimeters long
• Shoot tip snaps off and dies

Upward-climbing rose shoot borer (Blennocampa elongatula)

• Mining tunnels in the direction of the Triebspitze
• up to 10 centimeters long
• Drill hole often under a spike
• Crumbs of feces at the drilling hole
• Egg-laying from April

Fight:

• Cut off affected shoots down to the healthy wood

Rose leaf miner (Coptotriche angusticollella; Emmetia angusticollella, Tischeria angusticollella)

damage picture:

• Upper side of leaf: light colored space mines
• e.g. T.: whole leaf affected
• inside the mine: light-colored larva
• easily recognizable in the backlight

Fight:

• remove affected leaves

Rose jewel beetle (Agrilus cuprescens)

damage picture:

• mining larvae in the shoots of roses
• discoloration of the shoots
• spindle-shaped swelling of the shoots
• cracks on the surface
• shoots break off
• reduced sprouting or complete failure
• dried buds
• Beetle hatches in June, feeding damage (negligible)

Fight:

• Cut back affected shoots

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