HomeRaspberriesRaspberries: Leaves are physically damaged (chewed, holes, etc.)

Raspberries: Leaves are physically damaged (chewed, holes, etc.)

Several insects feed on leaves of raspberries, and their feeding patterns are distinctive. These include:

Raspberry leaves are a favorite food of Japanese beetles.

Six japanese beetles on raspberry leaf. Beetles that are sitting along are sticking one leg out into the air.

Two japanese beetles mating on a raspberry leaf. Leaf appears chewed with multiple holes torn in tissue.

Raspberry leaves with multiple round-oval beetles on leaf surface. Beetles are size of pennies, with shiny bronze shell and shiny green head. Lower leaves are sketelonized with only veins remaining.
Japanese beetles on raspberry bush. Photo courtesy of Heather Faubert, URI Extension.

More raspberry Japanese Beetles (White Grubs) information

Raspberry fruitworm (Byturus unicolor) prefers red and purple raspberries. Fruitworm adults limit their feeding to between the veins, skeletonizing unfolding leaves.

Raspberry bush with developing fruit and green leaves. Some leaves have no leaf tissue in-between veins. Thin strips of leaf veins can be seen near eaten sections as the tender tissue surrounding veins was eaten first.
Raspberry fruitworm damage to leaves. Photo courtesy of Heather Faubert, URI Extension.

Adults also feed on buds, and open flowers but the damage is usually minimal. Eggs are deposited on swollen unopened flower buds, inside buds or on developing fruit.

Close-up of closed raspberry buds. A brown-bodied beetle is hanging upside-down on one bud; beetle is same size as raspberry bud. A single green egg is on the raspberry bud. The egg is an elongated pill shape with rounded corners and is as long as a raspberry thorn. .
Adult raspberry beetle and a single egg on the unopened bud.

Larva hatch and bore into the receptacle tissue. When harvest fruit is picked larva often remain attached to the cup-like interior of the fruit and become a contaminant to harvested berries.

Raspberry fruit with a tan larva sitting on drupelets. The stem and receptacle is half-way removed from the fruit, and the receptacle is marked by a grooved tunnel traveling down into the fruit. The larva is roughly as large as a raspberry drupelet and appears stripy from its many body segments.
Raspberry fruit with raspberry fruitworm larva on surface. Note the tunnel in the receptacle.

More raspberry fruitworm information

Raspberry Sawfly (Monophanoides geniculatus) larvae can be very damaging to raspberry leaves. On rare occasions of heavy infection, only the larger veins remain uneaten.

Raspberry leaves with long, serrated holes eaten into interveinal tissue. The leaf veins remain uneaten.
Raspberry leaves showing characteristic sawfly damage.

 

Microscopic image of raspberry leaf underside. Two eggs are attached beside the vein. Eggs are translucent, and golden-green in color.
Raspberry sawfly eggs.

 

A green caterpillar covered in green-yellow spines sitting on a leaf.
Raspberry Sawfly (Monophadnoides rubi) larva.

More raspberry sawfly information

Leafminers affect blackberries more than raspberries. They also belong to the sawfly family. Leafminers will consume tender inner-leaf tissue. Damage is most visible when leaves are held up against the light.

A white larva on a leaf surface surrounded by pieces of black, pill-shaped frass. Larva looks similar to a maggot, with angular junctions between body segments and a black, triangular head. The larval body is translucent and a black stripe of frass is visible inside of its body.
Blackberry leafminer (Metallus rubi) larva.
Backlit raspberry leaf with large swaths of translucent tissue. Translucent tissue is irregularly spread across the bunch of leaves. Damage is rarely evenly distributed across the central vein.
A blackberry leaf with characteristic leafminer damage.

More leaf miner information