Citrus Gall Wasp
The Citrus gall wasp, known in the world of science as Bruchophagus fellis, is a native insect pest of Australia that feeds on the Australian finger lime or Citrus australasica. Traditionally, it has infested citrus trees in the regions of Queensland and the central and norther coast of NSW, but it is now found in the citrus trees that grow in the central inland. Recently, even backyard trees planted in Griffith City, Sunraysia, and the Riverland areas found it troublesome.
Characteristics of the Citrus Gall Wasp
Citrus plants are susceptible to attacks from the citrus gall wasp, however lemons, grapefruit, Troyer citrange, and rough lemon seems to be its important prey. Easily identify the infestation of these pests by familiarizing yourself with its characteristics as listed below:
no special trait a part from the regular type of wasps
exhibits a black body
red tinted eyes which covers most of the regions of its head
brown translucent wings
insects injecting larvae on your trees
Symptoms of Plants Infected with Citrus Leaf Miner
The disaster brought by the Citrus Gall Wasp begins when the female citrus gall wasp starts laying its eggs on the narrow stems of the citrus trees. It will take it only two to four weeks to hatch before it starts feeding on the branches of your precious citrus plants for nine to ten months. When this happens, you will notice swelling of stems that leads to the formation of small galls or pockets on your plants.
Seasonal Damage of the Citrus Gall Wasp
The Citrus Gall Wasp matures during late spring, which is also the beginning of the burrowing on the leaves of your trees. This is the time when you will see the adult gall wasp laying eggs on the stems of your plants and pestering the new young stems.
Citrus Gall Wasp Control
If this is not properly addressed, then it is very much possible that your plant will lose its vigor and die. You may choose to use one of the following methods to help eliminate these pests from your trees:
Chemical Control
Methidathion or Supracide is the only chemical that is registered to help control the spread and growth of the citrus gall wasp. It is sprayed on plants to help control its growth, nevertheless it will not completely eliminate these pests on your plants.
Typically, this treatment is applied on the trees for four weeks to guarantee that these pests will not mature and spread further damage on your citrus plants.
Cultural Control
To help reduce the infestation of the citrus gall wasp, some farmers make use of the following cultural approaches:
hedging operation
pruning operation
skirting operation
reduction in the amount of spring leaf flush used by farmers
reduced amount of fertilizer as research shows that those with high fertilizer seem
to attract more citrus gall wasps
reduced use of under-tree sprinklers because higher humidity attracts the growth
and spread of these wasps
Biological Control
Use of parasites and predators may also be used to control the growth and production of the citrus gall wasp. These include the following:
Megastigmus brevivalvus
M. trisulcus
Bugs for Bugs located in Munduberra, Queensland is the only commercial of parasitoids tat will help naturally eliminate these pests from your citrus plants. However, this comes in limited supplies and is only available during late October until early November. It is best to request this in advance from them if you do intend to safeguard your plants from these types of infestations.
Prevention and Monitoring of the Citrus Gall Wasp
It is highly recommended that farmers check the plants they buy from possible symptoms of citrus gall wasp infestation. If the notice any of these, then they may immediately return it to the seller for it to be replaced. This is the best preventive measure one can do in order to help rid your plants from these pests.