Why use Catch T?

Why use Catch T?

Catch T is a simple and effective, white, double sided, sticky trap, used for the monitoring of apple (Hoplocampa testudinea) and pear sawfly (Hoplocampa brevis). Apple and pear sawfly can cause devastating damage to top fruit. The damage is caused when sawfly larvae feed on the developing apple or pear fruitlets in late spring. The sawfly damage eventually causes fruit to drop from the tree, ultimately reducing crop yield.


What is Catch T?

Catch T is a white sticky tape trap which is used for monitoring apple and pear sawfly in orchards. Each pack contains two rolls of Catch T. Each roll consists of 100 m long x 15 cm wide Catch T tape.

Front view of Catch T tape.

Each roll of Catch T is 100 m long x 15 cm wide


How does Catch T work?

Catch T has been developed with a specific shade of white  that is particularly attractive to the sawfly  and does not reflect white UV light. The shade of white in Catch T acts as a ‘super blossom’ to the sawfly adults, luring them away from the blossom on the trees. Catch T is the same shade of white as the Rebell White trap. The Rebell White trap has been widely used by growers and is proven to be highly attractive to sawfly species.


What is apple sawfly (Hoplocampa testudinea)?

Sawflies belong to the order Hymenoptera, the same family as bees, ants and wasps. Both the male and female adults have black upper bodies and are orange underneath. Female apple sawfly adults are larger than the males and have a noticeable brown ovipositor (saw-like) which is clearly visible.

The neonate larvae are whiteish in colour and have a black head with clearly visible eyes. Once fully grown the larvae are around 12-13 mm long and have a brown head. Apple sawfly larvae have three pairs of true legs on the foremost segments and six pairs of prolegs on abdominal segments 2-7.


What is pear sawfly (Hoplocampa brevis)?

As with the apple sawfly, the pear sawfly also belongs to the order Hymenoptera. The adult pear sawfly is yellowish in colour and also has a noticeable ovipositor. The larvae are cream to yellowish in colour, with a yellowish head. The final instar reaches approximately 10 mm in body length.


What damage do apple and pear sawfly cause?

The apple and pear sawfly cause damage to the fruit when the young larvae burrow into the flower receptacle, often just beneath the skin, which appears as a ribbon scar. Later larval stages burrow into the fruit, making large holes as they go. Once the sawfly larvae have burrowed into the fruit they feed on the flesh and seeds and cause the fruit to drop during early summer.


What are the symptoms of apple and pear sawfly?

Early symptoms of sawfly feeding damage can look like a ribbon scar on the fruit. This sawfly damage is superficial and is caused when the early instar stages mine around the developing fruitlet. Once the larvae are older they burrow inside the fruit, the fruit can appear swollen or deformed in shape. A round hole can often be seen near the calyx, that is surrounded by wet frass.

Apple tree showing damage by apple sawfly.

Apple sawfly damage


What pest can apple and pear sawfly be confused with?

The codling moth (Cydia pomonella) causes similar damage to that caused by the apple and pear sawfly. Both pests leave significant holes in fruits, however the codling moth larvae tend to be seen later in the season. Codling moth larvae differ from sawfly larvae in appearance by having five pairs of prolegs, as opposed to six pairs of prolegs that sawfly larvae have. The frass of sawfly larvae is also wetter than that of lepidopteran larvae such as codling moth.


What is the life cycle of apple sawfly?

The apple sawfly is univoltine, meaning it only has one complete life cycle per year. The adults emerge just before the pink bud stage of early flowering varieties (BBCH 59) and fly during the blossom period. After emergence the females soon start laying their eggs singly in the receptacle of flowers using their saw-like ovipositor. Females tend to lay their eggs once temperatures have reached 11°C. The larvae take between one and two weeks to hatch out, which usually occurs shortly after petal fall.  

The neonate larvae hatch and mine into the fruitlet, causing the symptomatic ribbon scar. Later larval stages tend to move to other developing fruit, burrowing and feeding on the internal tissues and seeds. These larvae create large holes in the fruit which are filled with wet frass. The infested fruit will eventually fall from the tree.

The larvae go through five larval instars in total. The final larval instars occur during late June to early July.  At this point they drop to the ground and form cocoons in the soil where they overwinter.  The apple sawfly then pupates in the spring.


What is the life cycle of pear sawfly?

The adult pear sawfly begin emerging from the soil at the pre-bloom stage, with the majority emerging over a seven day period. The females lay their eggs singly towards the centre of the calyx with their saw-like ovipositor. After one to two weeks the eggs will hatch, and the young larvae will emerge. The larvae burrow into the developing fruitlet feeding on the flesh and the seeds. The larvae of pear sawfly can enter and exit several fruits over a period of 24 to 34 days. The larvae go through five different instars in total.

Once the larvae reach the final instar (May to mid-June) they drop to the soil where they burrow and form a cocoon. The pear sawfly remains in the soil until the following spring when they pupate and emerge as adults. As with the apple sawfly, the pear sawfly only has one generation per year.  


Why should I monitor for apple and pear sawfly?

If left untreated, apple and pear sawfly can cause significant levels of damage. There is only a small window of opportunity for approved plant protection products to be applied to orchards. Using Catch T to monitor the pest allows growers and agronomists to make well informed decisions on the timing of applications of pesticides.


How can I control apple sawfly and pear sawfly?

Only insecticides that are that permitted for use in top fruit can be used to control apple and pear sawfly. Pesticides must always be recommended by BASIS qualified advisors.


How to use Catch T?

Catch T rolls need to be cut to lengths of approximately 0.8 to 2.0 metres to make individual catch tapes. The length of catch tapes used will depend on the height and spacing of support wires in orchards if they are present.

Catch T should be fixed vertically between two horizontal support wires. It is important to keep the tapes taught between the wires and to allow sufficient overlap at the top and bottom so that the catch tapes can be stapled in position to secure. It is recommended that Catch T tapes are fixed at a minimum of 1 metre above the ground. Apply Catch T at regular intervals throughout the orchard and stagger in a ‘zig-zag’ fashion between rows. After flowering, remove Catch T immediately to prevent unwanted catches of pollinators and beneficial insects.

Andermatt recommend using a rate of between 150 and 250 catch tapes per hectare. The lower number of catch tapes can be used in younger orchards or orchards with lower pest pressure. The higher number of catch tapes should be used in older/denser orchards or if the orchards are known to have historically high pest pressure.


Catch T tape hung vertically between two wires.

Catch T should be hung vertically between two wires in the orchard


When should I apply Catch T?

Catch T should be applied shortly before blossom, to ensure that the Catch T tapes are in place in time for apple and pear sawfly emergence.


Is Catch T safe to use?

Catch T is non-toxic but for ease of use we recommend wearing suitable gloves.



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