Macdonald Catchment Black Willow Monitoring

The Willow Warriors MacDonald River Black Willow monitoring project commenced in September 2008 when 2 members of the willow warriors’ landcare group and 6 Students from Pacific Hills Christian School at Dural, doing their Duke of Edinburgh Bronze Award, had a willow treatment training day on the lagoon on the St Alban Common. On the way home willow warriors Ian and Jeff, noticed many black willow seedlings that were growing into view amongst the reads along the river and decided a monitoring paddle along the river was urgently needed. The river needs rain in the catchment so you can paddle the river otherwise it is a series on ponds in the sandy bottom and occasion drifts of deep soft sand making the walk challenging. In November 2008, after some rain, we organised a four day camp on the river with the group from Pacific Hills Christian School at Dural and we were also joined for two days by 5 DofE candidates and Jono from Macmasters Beach SLSC. Over the four days we paddled and walked the 23 kilometres from the Upper MacDonald Bridge to St Albans Cemetery treating about 800 black willows and mapping another 70, where we ran out of time to treat them. This included many female plants that were in flower as dispersing seed at the time we treated them. We poison the willows using roundup bioactive, and with our trusty tool kits, which include chisel and mallet, folding saw and secateurs, we either cut and paint, scrap and paint, or stem inject the willows. We have done another 3 trips to do follow up and extend the treatment down to Lower Macdonald and the junction with the Hawkesbury River. We have contributed 740 volunteer hours in total and treated 1,100 black willows. In addition we have had two other activities on the St Albans Common Lagoon treating an estimated 500 black willow stems on private land at the southern end of the lagoon. This has contributed another 70 hours to the project. We have also started working our way up Mogo Creek treating the isolated black willows up along the creek and have treated 50 to date on four properties. There are two other major black willow sites to be treated in the valley over winter 2009. One is a partly treated large gallery of seven year old plants on private land on the western side of the St Albans Common Lagoon. The second is a number of black willows scattered around a side lagoon on the eastern side of the valley upstream of St Albans. In late 2008 a contractor was flown into the junction of Yengo Creek and the MacDonald River to treat a gallery of seedlings at that point and then walked back to higher MacDonald monitoring the river for other black willows. Because of this gallery and the number of black willows we have found along Mogo creek we will need to do a walk or paddle from further up the catchment probably walking in from the Putty Road to ensure we have found the upper limits of the black willows. The Macdonald River and Mogo Creek start within the Yengo NP which is part of the Greater Blue Mountains World Heritage Area and the spread of black willows up the river would diminish these world heritage values. Downstream of the World Heritage Area the river flows through a valley that was settled in the early 1800’s and along with land at Wisemans ferry was one of the first successful food growing areas of the new colony of NSW. Prior to the 1950’s the river was navigable up to St Albans and the area now occupied by the St Albans Common lagoon was pasture and peach orchids With heaving logging in the area, poor land management practices and several years of heavy flooding in the late 1940’s and early 1950’s the river is now heavily silted. Also sand deposited where Mogo Creek joins the Macdonald have formed the lagoon on the Common. St Albans common is one of two remaining “Commons” in New South Wales. With commoners in the valley entitled to use the common to graze livestock. Black willows were probably introduced into the valley in the late 1960’s by someone growing them as plantation timber but unlike the poplars, where only the male trees were planted, both male and female trees were grown and they spread by windblown seed throughout the valley. In the mid 1990’s some landowners tried to control the black willows on their property learning from their mistakes as they went. In 2001 the community received funding from the Department of Land and Water Conservation to start the control of the Black Willows. This was not enough to complete the treatment and this was followed by a couple of years of government department restructuring where funding was not followed up. Then with a grant from the NSW Environmental Trust 2005-07 about 20,000 black willow saplings and seedlings were treated along the river from Yengo Creek to Wrights Creek and on the St Albans common and adjoining land. This grant was followed by a grant from the Hawkesbury Nepean CMA in 2007 to treat some more of the black willow seedlings in the St Albans Common lagoon. There was also a riverbank restoration funding program from NSW Fisheries, Hawkesbury City Council and the Hawkesbury Nepean CMA in 2007 which supported some ongoing treatment and monitoring. Black Willow mainly spread by windblown seed and a single tree can produce tens of thousands of seeds each spring and which can be blown over 50 km from the source. The primary treatment has taken 10 years to complete and apart for individual landowners monitoring their own property for new black willows and contractors treating them when working on other river restoration projects for landowners there has been no catchment wide monitoring project. As a result the untreated black willows have continued to re-infest sites cleared of black willows and the new black willows have grown over two or three years to an age where they started producing seed. I say this because this project demonstrates a few weaknesses in the current approach to weed management generally in New South Wales which are resulting in funds being wasted. • There does not seem to be any weed reporting system for mapping of weeds to ensure when funds are allocated that there is adequate resource to find and manage re-infestation for other seed sources. • Funding is allocated for short term treatment projects based on how much interested landowners can contribute rather than what is need to control the weed. And usually there is no resources allocated to combat re-infestation from other seed sources. • Funding and control programs are based around land tenure. Whilst a mosaic of restoration projects means not all animal habitat is rebuilt at the one time, it does mean a landowner who does not want to control the weeds on their property will re-infest adjoining properties and those landowners can suffer from burn out. This project demonstrates how groups of recreation river users like canoeists, fishermen and bushwalkers, can contribute to river restoration projects by assisting with monitoring activities. Through this they can build relationships with public and private landowners and so gain access to the river. When we have completed the primary treatment we intend to monitor the river and side lagoons annually in autumn for the next four years to ensure we find and treat all black willows growing into view through the Phragmites reeds. As the black willows are at the age where they can produce seed by the time they grow the 2 meters or more, into view in the Phragmites. We will then need to monitor the river for the next 6 years bi-annually or until we find no new black willows We are also monitoring the Hawkesbury River, side creeks and side lagoons to protect the investment by the landowners, our volunteers, the NSW Environmental Trust and the Hawkesbury Nepean CMA. But that’s another story. We would like to acknowledge the support we received for this project from the Macdonald Valley Association, NSW Environmental Trust, Hawkesbury City Council staff and the Hawkesbury Nepean Catchment Management Authority and of course our volunteers

 

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