Weeds of the Cooks River Valley – draft


Weeds of the Cooks River

The Mudcrabs currently work on 15 sites along the Cooks River. Many of these are bush regeneration sites. Regeneration usually involves 3 primary activities for our volunteers. Depending on the site these are:
Landscaping – terracing and major site preparation (contractors)
Planting native species – selection and timing are important
Weeding – an on-continuous process until site viability is established

Weeding is the primary activity that The Mudcrabs volunteers are involved with. It is through targeted weeding that we allow space for the native plantings and remnant natives species to re-establish and develop an ecosystem that reflects the original state of the bushland that was the Cooks River Valley.

Identification of priority weeds and applying the right strategy will yield the best results. This section is designed to help new-comers to bush regeneration understand what we do on the various sites and how they can help. Gaining skills in weed identification is an important capability for our volunteers. Most of our bushcare activities start off with an identification of what weeds we will target for the session and what techniques we will employ to remove these weeds.

Our experienced botanists and bush regenerators have put together a list of the weeds that we target across our Cooks River sites. Being able to identify these and understand how to eliminate/manage them really helps is reestablishing native zones that support and encourage the return of original ecosystems.

Below is a table of the main weed targets. Which ones we focus on in a session is determined by how numerous/obvious they are and how soon they are to throwing seed or replicating. Some weeds (annuals) have a short life-cycle (seed, grow, drop seeds, die) e.g. Ehrharta, others are are long-lived (perennial) and reproduce continuously e.g. Trad.

In our weed table we have selected the top 62 weed species and have assigned a “Significance” to each one:
1) means a focus weed that we remove whenever we encounter it
2) means that we consider whether it is worth the effort of removal
3) means that the weed is relatively uncommon in the Cooks River valley but worth removing when we encounter it.

Common NameScientific NameSignificanceFlowering/Seeding
Turkey RhubarbAcetosa sagittata1
Crofton WeedAgeratina adenophora1
Madeira VineAnredera cordifolia1
Moth VineAraujia sericiflora1
Balloon VineCardiospermum grandiflora1
CeltisCeltis australis1
Green CestrumCestrum parqui1
Camphor LaurelCinnamomum camphora1
Seaside DaisyErigeron karvinskianus1
Cockspur Coral TreeErythrina crista-galli1
Coral TreeErythrina X sykesii1
Yellow Ginger LilyFiedychium gardnerianum1
Honey LocustGleditsia triacanthos1
English IvyHedera helix1
Kurnell CurseHydrocotyle bonariensis1
Coastal Morning GloryIpomoea cairica1
Blue Morning GloryIpomoea indica1
LantanaLantana camara1
HoneysuckleLonicera japonica1
Primrose WillowLudwigia peruviana1
Mickey Mouse PlantOchna serrulata1
African OliveOlea europaea ssp. africana1
Asthma WeedParietaria judaica1
KikuyuPennisetum clandestinum1
Asparagus FernProtasparagus aethiopicus1
BlackberryRubus fruticosus spp1
Chinese TallowSapium sebiferum1
CassiaSenna pendula var. glabrata1
Potato VineSolanum jasminoides1
RhusToxicodendron succadenaneum1
TradTradescantia albiflora1
Weeping Love-grassEragrostis curvula1
African Fountain grassPennisetum setaceum1
Golden Wreath WattleAcacia saligna2
Box ElderAcer negundo2
Giant ReedArundo donax2
Carpet GrassAxonopus affinis2
Common CouchCynodon dactylon2
Panic VeldtgrassEhrharta erecta2
Lemon-scented GumEucalyptus citriodora2
Fishbone FernNephrolepis cordifolia2
Climbing AsparagusProtasparagus plumosus2
Buffalo GrassStenotaphrum secundatum2
Mist-flowerAgeratina riparia3
Tree of HeavenAilanthus altissima3
Whisky GrassAndropogon virginicus3
Mother-Of-millionsBryophyllum delagoense3
Live PlantBryophyllum pinnatum3
Cabomba, FanwortCabomba caroliniana3
Flick WeedCardamine hirsuta3
Ribbon Plant, Spider PlantChlorophytum comosum3
Pampas GrassCortaderia selloana3
Cape IvyDelairea odorata3
Silky OakGrevillea robusta3
JasmineJasminum polyanthum3
Baby SmilaxMyrsiphyllum asparagoides3
Japanese KnotweedPersicaria capitata3
Canary Island PalmPhoenix canariensis3
Lippia, Carpet WeedPhyla nodiflora3
PolygalaPolygala myrtifolia3
Black LocustRobinia pseudoacacia3
Blue PeriwinkleVinca major3

Weeds & Removal Strategy

Most of these weeds can largely be managed via hand weeding. We try to get to them before they throw seed. As many are annuals, we can interrupt the seeding cycle and significantly reduce their impact and give the native plants an advantage.

Kikuyu is a particularly challenging weed along the river as it is very vigorous and spreads quickly in optimal conditions. This virulent weed species continues to be a primary focus at many of our Mudcrabs sites along the river.

Weeding References

Native and Weed Look A-likes – Hornsby Council
Common Riverbank Weeds – Greater Sydney
Sydney Weeds Network
Bushland Weeds of Sydney – AABR

Weed List – for site surveys