00 – Introduction

Weeds Calendar

A weed is a plant growing where it’s not wanted. That doesn’t mean it’s bad, just bad here. Some weeds can be beautiful. In the suburbs, where most weeds have escaped from gardens into the bush or along waterways, they were once highly-prized ornamentals, grown for their attractive foliage or flowers.

These days, even garden use of such pretty pests as Ochna and Easter Cassia is frowned upon, because of the danger to local habitats when they invade. But that doesn’t make them any less attractive. Seeing them in their original native habitat in South America, Asia, Africa or Europe would be a delight.

The damage weeds do is fairly obvious. Thickets of Lantana, Ochna, Privet and other shrubby weeds crowd out local species and upset the balance. They poison local fauna, and cause erosion. They make areas of bushland into impenetrable scratchy forests, reducing amenity, biodiversity and habitat health.

Camphor Laurel fruit are toxic and can kill birds in great numbers, especially rainforest pigeons. They also suppress local insects and other native plants.

Chinese Elms can quickly become monocultures where virtually nothing else will grow.

Weedy vines grow rampantly up trees and across the canopy, suffocating trees and pulling them down.

Aquatic plants like Wild Taro poison the water they grow in, upsetting habitat for fish, reptiles and frogs.

Less well known are the benefits of weeds. In terms of environmental health, even weeds are better than bare earth. Small birds and mammals forage in patches of Lantana and weedy grasses. The fruit of Ochna is high in fat content, relished by local birds.

But the benefits of weeds are far outweighed by the harm they cause.

In this calendar we have tried to show the most attractive features of some of our worst weeds. Why? Because a beautiful picture is much more likely to create a lasting impression. The irony of something beautiful but bad can help make these examples more interesting and memorable.

When you turn to a new month you may be amazed at the beauty of the image you will be looking at over the next few weeks. Around Easter time you’ll see the flowers of the Easter Cassia and you will be reminded to target these yellow bullies of the bush with a snip of the secateurs and a dab of herbicide. Don’t hesitate — after all, you will still have the glorious photograph to admire, safely away from any vulnerable ecosystems.

Nature is remarkably resilient. Most of our suburban land is seriously disturbed and degraded, but with a little encouragement of the good and some deft removal of the bad, the bush can bounce back.

We hope these weeds will inform you about the enemy in a positive way, and encourage you to restore some of the natural balance in your local area.

To find out more about weeds, visit our web site at www.sown.com.au and check out the “Weeds to Whack” section.

AcknowledgmentsThe stunning photographs in this collection are mostly the work of Mark Crocker using Canon EOS digital cameras with a variety of lenses (principally a 100mm macro). To capture the weeds in season Mark has been out in the catchment with his camera over several years.

Thanks to Dr Don Sands and the Richmond biirdwing recovery Network for the Richmond Birdwing Vine photo (native alternative for Dutchman’s Pipe).

Thanks to Dr Sheldon Navie for help with the text and the photo of the native alternative Pseuderanthemum variabile (Love Flower).

We have had a number of people check the calendar for scientific accuracy, but any mistakes are ours, not theirs.

We could not have brought this project to fruition without the generous support of the Brisbane City Council through its Water Resources and Habitat Brisbane programs.

Special thanks also must be recorded for strong supporters of SOWN including local BCC councillors , local State and Federal MPs.

Local organisations assisting SOWN include Broncos Leagues Club.

Above all, we thank the members of SOWN who spend countless volunteer hours in their local green places, hacking, slashing, cutting, pulling and killing weeds, replacing them with local native species.


Draft Weeds Calendar design
Chinese Elm (Celtis sinensis) Photo: Mark Crocker
Black-eyed Susan (Thunbergia alata) Photo: Mark Crocker
Cat’s Claw Creeper (Macfadyena unguis-cati) Photo: Mark Crocker
Climbing Asparagus Fern (Asparagus africanus) Photo: Robert Whyte
Cat’s Claw Creeper (Macfadyena unguis-cati) Photo: Mark Crocker
Mistflower, Creeping Crofton Weed Mistweed (Ageratina riparia) Photo: Mark Crocker
Ochna (Ochna serrulata) Photo: Mark Crocker
Milk Thistle (Sonchus oleraceus) Photo: Mark Crocker
Lantana (Lantana camara) Photo: Robert Whyte
Dandelion (Taraxacum officinale) Photo: Mark Crocker
Ochna (Ochna serrulata) Photo: Mark Crocker
Billy Goat Weed (Ageratum houstonianum) Photo: Mark Crocker
American Nightshade (Solanum americanum) Photo: Mark Crocker