Description

The suborder name Rhopalocera refers to their antenna and means “clubbed horn”. Their antenna is different from those of moths. They are generally very colourful. Their wings are covered in tiny, overlapping scales, hence the “Lepidoptera” classification. Bright wing colours usually warn off predators; some wing patterns will provide camouflage when the butterfly is resting and some will mimic other species which may be known by predators as one to avoid. Butterflies have modified mouthparts that enable them to suck up nectar. The proboscis is like a long straw and is coiled up when not in use. They are very similar to moths but there are some general differences although there are exceptions: Butterflies antennae tend to be thin with a club at the tip- moths have feathery antennae Butterflies tend to fly around during the day - moths are generally nocturnal Butterflies hold their wings together above their bodies when they are resting- moths usually hold their wings flat or folded Butterflies are usually more colourful than moths.

Adult size: 12-30 mm wingspan

Out and about

Springtime is when butterflies emerge from their pupa and then lay eggs which in turn means that caterpillars will be hatching late spring and over summer and autumn. This time of year has many flowers out for the adults and lovely new growth on plants for the caterpillars to eat. Butterflies are found all over the world, except in Antarctica.In Australia there are approximately 400 species found in virtually every habitat and widespread throughout the country.

Reproduction and Life cycle

Butterflies go through complete metamorphosis, having four stages in their life cycle: egg, larva, pupa and adult. The female will lay her eggs on plants where the caterpillars will have a ready source of food. Some butterflies lay eggs singly; others will lay them in clusters. Eggs are laid in spring, summer or autumn, depending on the species. Caterpillars are extremely vulnerable to predators so the females will lay hundreds of eggs as only a small percentage will reach adulthood. Environmental factors and species will often determine how long it takes for the eggs to hatch. Once the larvae hatch they begin eating leaves and continue to eat, moulting several times and growing rapidly until they are fully grown. They will then make a cocoon in which to pupate; transforming from a caterpillar to a butterfly emerging in spring. The average lifespan of a butterfly is two to three weeks.

To deter

To control

Action is taken against the larvae. See the entry on caterpillars for more information.

Plants to repel

Chamomile / Dill / Hyssop / Mint / Rosemary / Sage / Southernwood / Thyme / Land cress (Barbarea vulgaris) can be planted near brassicas as a ‘trap and kill’ plant.Moths and butterflies are attracted to this plant, favouring it over brassicas, and lay their eggs on it. When the larvae hatch and begin to eat it they will actually be poisoned and die. Land cress belongs to the mustard family, and is also known as winter rocket, bittercress, herb Barbara, upland cress.

Plants to attract

Ajuga / Astralagus / Heather / Lavender / Red clover

Predators

Birds are the main predator of butterflies but other insects will prey on the larvae - Ground beetles /Lacewings / Tachinid flies / Parasitic wasps / Assassin bugs. Trichogramma wasps will parasitise the eggs

Why they are both Beneficial & Pest

Butterflies themselves are not a pest as they don’t eat plants feeding instead on nectar and pollen. In fact they are important pollinators of plants. It is their larvae, the caterpillars, that can cause so much destruction. As with many insects in the garden, it is important to observe just how much damage is being done and if it is really a concern. Ideally, we should discourage them from laying the eggs on our vegetables in the first place, The caterpillars of all butterflies need to eat something, but many of them don’t harm our vegetables and the adults are extremely beautiful. For example the larvae of the Orchard swallowtail butterfly (Papilio aegeus) occasionally does a small amount of damage to citrus trees, but not enough to really be a pest. Some are pests of specific plants, such as the Cycad blue butterfly (Theclinesthes onycha) and Cabbage white butterfly (Pieris rapae). The cycad butterfly has never bothered us, but if you are attached to your cycads then you would want to watch out for it. We’re always on the lookout for the cabbage white butterfly, as it can do extensive damage to vegetable crops.