A diverse ecosystem of trees, shrubs and wildflowers is what koalas need
Our koala tree planting projects, in central Victoria, include 35 to 40 species of plants. But why? Koalas only eat one species of gum-tree, don’t they?
No!! And anyway, there’s more to a koala planting than just food trees.
Koalas eat many, many species of eucalyptus. In the You Yangs we have recorded them eating every single species of eucalypt that grows there – including non-native species! We have seen them eating Lemon-scented Gum, Swamp Yate, Sugar Gum, Bushy Yate, Spotted Gum and Brown Mallet.
So on every tree planting site what we usually plant is approx 3 to 5 eucalyptus species. We only plant those gum trees that should naturally occur there. Some are highly-preferred koala eating trees (primary browse trees), others are only eaten by koalas occasionally. But all are important.
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Here’s a list of the eucalypts we often plant for koalas, and why:
River Red Gum Eucalyptus camaldulensis
Primary koala browse tree | Beneficial Insect tree | Mammal food & shelter plant | Bird food & nest plant | Draws deep underground water to surface
The number one primary browse tree for koalas in the You Yangs and Little River areas. Probably also the most preferred koala tree in the Moorabool and Barwon River systems. Has a very wide distribution, along rivers, creeks and drainage lines all over Australia especially the drier areas.
Melbourne Yellow Gum Eucalyptus leucoxylon connata Endangered
Primary koala browse tree | Beneficial Insect tree | Mammal food & shelter plant | Bird food & nest plant | Draws deep underground water to surface
The second most-preferred eating tree for koalas in the You Yangs.
Red Box Eucalyptus polyanthemos
Secondary koala browse tree | Beneficial Insect tree | Mammal food & shelter plant | Bird food & nest plant | Shade tree
Only eaten by koalas occasionally in the You Yangs, however it is important to plant this tree as it is a very important shade tree for koalas on hot days. Flowers heavily, very important for birds.
Grey Box Eucalyptus microcarpa
Secondary koala browse tree | Beneficial Insect tree | Mammal food & shelter plant | Bird food & nest plant
This tree is eaten by koalas occasionally in the You Yangs, but not very common in our research area. It was probably a much more important koala food tree on the Balliang Plains, where it was once very common. Flowers heavily, very important for birds including the endangered Swift Parrot.
Yellow Box Eucalyptus melliodora
Secondary koala browse tree | Beneficial Insect tree | Mammal food & shelter plant | Bird food & nest plant | Draws deep underground water to surface
Important primary browse tree for koalas in the You Yangs, though not very common in our research area. Naturally grows adjacent to River Red Gum on fertile moist areas. Very important for birds.
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The trees we plant are carefully considered one year before we begin planting. The tree order is designed to suit the site location. We only plant the trees and shrubs that once grew there naturally.
Aside from the eucalypts we also plant a wide range of species, genera and families of plants. Some assist the gum trees to grow fast and strong (nurse plants), other trees help koalas survive hot days, others encourage beneficial insects and lizards, others feed birds that help pollination and forest health. A koala forest without these other creatures does not work.
An ecosystem is a 3D jigsaw: take a lot of pieces out and the whole thing gets floppy and falls apart.
Nurse Plants for Koala Trees:
Nurse plants help other plants to grow, either by slowing the wind, controlling erosion, fixing atmospheric nitrogen into the soil so it can be used by other plants, or by attracting beneficial creatures or repelling pests. Here are some of our favourite nurse plants:
Black & Silver Wattle Acacia mearnsii & A dealbata
Shade tree | Nurse tree | Beneficial Insect tree | Small mammal food plant | Bird food plant | Nitrogen fixer
These large wattles grow very fast, and often the largest plant in the project after 2 years. They slow the wind, provide shade and moisture for the eucalypts. Their beautiful heavy flowers attract beneficial insects and birds. Their seeds feed cockatoos, bronzewings and ants. Seedlings start popping up in just a few years. They only live about 15 years, and even when they are dying they are still providing food for Sugar Gliders and birds – their abundant sap is rich in sugars and keeps many animals alive during winter.
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Trees for koalas on hot days
On hot days koalas often seek shelter in leafy, shady, non-eucalyptus trees.
Blackwood Acacia melanoxylon
Shade tree | Beneficial Insect tree | Small mammal food plant | Bird food plant | Nitrogen fixer
This is also a large wattle, but this one is very long-lived and slow growing. Also flowers heavily and attracts insects, birds and small mammals. A very important shade tree for koalas on hot days.
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Plants that attract beneficial insects
Sweet Bursaria Bursaria spinosa
Shade tree | Beneficial Insect tree | Bird nest plant
A very important component of our landscape that has been mostly lost. This beautiful slow-growing tree can live to hundreds of years old. It has sweet-scented white flowers that attract insects including jewel and scarab beetles, copper butterflies and wasps and bees.
Read more in these fantastic blogs: https://www.recreatingthecountry.com.au/bursaria-spinosa-sweet-bursaria.html and https://tanyaloos.com/sweet-bursaria-in-masses-of-flower/
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Smooth, Pale and Black-anther Flax-lily Dianella longifolia var longifolia & var grandis, and D revoluta
Beneficial Insect plant | Small mammal shelter plant | Bird food plant
These plants grow as tussocks that slowly keep spreading. Their beautiful blue flowers attract Blue-banded Bee, Teddy Bear Bees and carpenter bees. Small mammals use tussocks as shelter. Birds eat the blue berries.
Yellow-banded Dart Ocybadistes walkeri butterfly needs this plant.
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Common & Clustered Everlastings Chrysocephalum apiculatum & C semipapposum
Beneficial Insect plant
These plants can spread over the ground in good seasons, producing beautiful yellow papery flowers.
This plant attracts the Australian Painted Lady butterfly.
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Woolly New Holland Daisy Vittadinia gracilis
Beneficial Insect plant
This plant grows very fast, flowers and seed heavily in the first year. We had them in tree guards, and just 12 months later the plant had filled the guard and grown into a triangular shape, and was covered in seed. Wind dispersed the seed, so we are sure that many baby daisies will be popping up everywhere!
Attracts native bees
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Showy Podolepis/Plains Copper-wire Daisy Podolepis jaceoides/linearifolia
Beneficial Insect plant | Erosion control
We have been very impressed with the tenacity of this plant in heavily disturbed, scoured areas depleted of topsoil. Plus the flower is huge!
Attracts native bees.
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Plants that feed native birds
Berry & Nodding Saltbushes Atriplex semibaccata & Einadia nutans
Beneficial Insect plant | Weed suppressor | Small reptile food plant | Bird food plant | Erosion control
Saltbushes are very important plants in our region – they are mostly ground-covers, they can thrive under trees, and they produce nutritious fruit that is very important to many birds and reptiles. Birds including Silvereyes, thornbills, Crimson Rosellas eat the fruit.
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Lightwood Acacia implexa
Beneficial Insect tree | Small mammal food plant | Bird food plant | Nitrogen fixer
Similar to Blackwood, but more hardy. It’s not as shady, but we can plant this in slightly drier sites than Blackwood, and it grows a bit quicker. Flowers and seeds very important food source for birds and insects. Like all wattles, makes nitrogen available in the soil.
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Tree Violet Melicytus dentatus
Beneficial Insect plant | Erosion control | Bird & reptile food plant
We plant heaps of this tough little plant. From windswept rocky sites on the plains, to shady fertile sites along rivers, this plant can manage and thrive where others give up. I’ve seen it less than 1 m tall, but probably many years old, in dry stone walls at Wurdi Youang – it was the only thing that survived sheep grazing. These small, prickly shrubs were visited by Superb Fairy-wrens, White-fronted Chats and Red-browed Finches, and I suspect some of them may nest in there.
I’ve also seen it 3m tall under old River Red Gums right on the banks of the Little and Moorabool Rivers. Turns out, there are probably two species – Melicytus dentatus, the taller and medium-sized, river-loving species: https://vicflora.rbg.vic.gov.au/flora/taxon/8c04cf97-95bf-425f-8a8f-f23f874c01ef and
Melicytus angustifolius subsp. divaricatus, the small, sometimes ground-hugging form that occurs mostly on the Victorian Volcanic Plain west of Melbourne. https://vicflora.rbg.vic.gov.au/flora/taxon/b1ebb93d-cc0a-427e-a59c-dd739fb7ab8d
The plant has sweet-smelling tubular flowers that are loved by small honeyeater birds and butterflies, and berries that are eaten by small lizards, birds including Crimson Rosellas and Currawongs.
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Plants that suppress weeds
Hop Goodenia Goodenia ovata
Beneficial Insect plant | Weed suppressor | Erosion control
We have been very impressed by the rapid growth and weed-smothering ability of this plant, even planted on very rough granite sandy soil. At You Yangs North, several are holding their own against Galenia – a very tough weed to control. At Moorabool Tributary, after just two years, many are 1.5m wide shrubs.
This plant attracts the beautiful Meadow Argus Junonia villida butterfly.
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Cut-leaf Daisy Brachyscome multifida
Beneficial Insect plant | Weed suppressor | Erosion control
If you want a showy little performer, and you have a woodland site in central Victoria, this plant is a ripper. It flowers almost all year! We’ve had tiny seedlings in tubes, flowering while we plant them.
This study by RMIT in Melbourne found Cut-leaf Daisy to be the native plant that attracted the most butterfly species. Skippers Hesperiidae, Little Blues : Lycaenidae , and Small grass-yellow Eurema smilax were all recorded visiting the flowers. https://researchrepository.rmit.edu.au/discovery/delivery/61RMIT_INST:ResearchRepository/12248008430001341?l#13259332060001341
Butterflies are particularly important to koalas, because they pollinate plants, including eucalyptus trees. Koalas need a constant supply of healthy gum trees, some young, some mature and some old – as each group provides them with something different and necessary. Young trees are sometimes easier for koalas to climb, old trees provide fantastic shade and insulation on hot days from their huge trunks. The rainwater running down the trunk and branches (stemflow) of an old eucalyptus tree may have special qualities – and this is how koalas drink.
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Read more about, and see species lists, for our specific tree planting projects here: https://www.koalaclancyfoundation.org.au/koala-tree-planting-projects/
