Friends of Rietvlei
Newsletter April 2008
Annual General Meeting
This important meeting is going to be held on THURSDAY 8 MAY 2008, at 7.30 for 8.00pm in our Education Centre. All members must please make every effort to attend. You are welcome to bring friends with you.
A very interesting power point presentation on “The Origin of Rietvei” will be given by Niel Van Wyk
Please note that the committee intends to apply to the Directorate of Non- Profit Organisations for formal N.P.O status, but for this application to be successful certain clauses needed to be inserted in our constitution and other amendments made. These amendments turned out to be quite numerous and it was decided to replace the present Friends of Rietvlei constitution with a completely new constitution that will conform to the requirements of both the Nonprofit Organisations Act, Act 71 of 1997, and the Income Tax Act, Act 58 of 1962 as amended.
  This new constitution is to be proposed to members at the AGM – please see website http://www.friendsofrietvlei.co.za for a copy of it. If you do not have internet access please collect a copy from the Rietvlei gate.
Membership Renewal
Along with the AGM comes the need for all Ordinary and Family members to make sure they renew their membership. The membership fees have been increased minimally as will be seen on the attached renewal form. Please use the form by paying at or before the AGM ……………. THANK YOU!!
Our previous Evening Talk was held on Thursday 6 March. Our speaker was Pat Holmes and she spoke on the restoration of fynbos. This interesting talk was augmented by a pamphlet she left for those who are interested in more detail on protocols for restoring lowland sand fynbos.
Remembering Rob Robertson
It was with sadness that the committee heard of the untimely death of an active member of Friends of Rietvlei. Rob died when knocked down accidentally by a car near Milnerton Lagoon. Rob was a sailor at Rietvlei as well as a quiet but determined action man. Rob took up the challenges of fighting developments that would harm the natural and human environments. His flat overlooked the Milnerton Lagoon and he objected to the proposed hotel development at the Milnerton Golf Course, the Milnerton Lagoon Mouth Development and the Potsdam Waste-water Treatment Plant expansion, amongst others. He was extremely thorough and meticulous in researching information and documenting the issues. He spearheaded the Potsdam Action Group, arranging meetings, writing reports and letters, and making sure that the decision makers heard his point of view. We will miss his friendly face and keen mind here on the edge of Rietvlei, but know that he now resides in a far more beautiful place. Our condolences go to Gert and the family.
The Typha Take-over
Bulrushes are taking over. In many of the reedbed areas around Rietvlei bulrushes are displacing other wetland plants, and in the Dolphin Beach ponds the water area is gradually disappearing under bulrush growth. But what is this reed and where does it come from?
Typha latifolia occurs naturally on all continents except South America and Australia, but it has been introduced there and now occurs world-wide; it is one of the most common of all aquatic plants. The reed has many common names in different parts of the world, we know it as bulrush, cattail, or by the British name reed-mace.
Although often a nuisance, they are extremely efficient in removing nutrients from water and are thus very effective filters. Bulrushes grow in wetlands, lakes, river courses, estuarine habitats and even in marshy coastal habitats which is predominantly fresh water. When conditions favour Typha they form dense monocultures, spreading rapidly by vegetative reproduction forming thick mats of rhizomes and plant litter. This impacts on other species by changing the habitat and forcing other plants out; they can rapidly close open water giving other plants few opportunities to establish. Typha seeds are dispersed by winds, in water, on the feet of birds and livestock, or by humans and machinery.
However, Typha is also a very useful plant and is used for many things. It is used as thatch for roofing; woven into mats, chairs, hats, etc; it is a source of fibre for rayon and a greenish brown paper; it is used as torches and tinder for making fires; the flower clusters are used for stuffing pillows and mattresses, and for insulation, dressing wounds, and lining diapers. Typha stands provide important food and cover for wildlife and birds, establishing habitat for many waterfowl. Many parts of the plant is also edible for human consumption and are an important source of protein in many parts of the world; rhizomes are dried and ground into flour or eaten as cooked vegetables; young stems are eaten raw or cooked; and the pollen is used in baking. Because of its very effective water filtering properties, Typha is widely used in artificial ponds to filter effluent and stormwater runoff in many parts of the world, including Cape Town.
Controlling excessive Typha growth is extremely difficult and can be quite costly, particularly in natural systems. Various methods have been tried and tested all over the world, but there is no easy way to control the plant.
Herbicides can be effective when applied when the plant is flowering, but the disadvantage is that the decaying plant material accumulates and results in hypertrophic conditions, this plant material also provides a good substrate for regrowth of Typha. Some herbicides may also have negative effects on other plant and animal life in the system.
Mechanical removal is difficult because of the depth and volume of the rhizomes, but it can be effective in reducing the size of infestations. Manual removal works best on small seedlings when they can be easily pulled out of the damp soil.
The best way to control Typha seems to be using fire and physical cutting in conjunction with flooding. If the reeds are burnt and/or cut when water levels are low, and then flooded, growth is considerably inhibited. An effective control can be achieved by a combination of mechanical and hand cutting at the end of the growing season and when water levels are low, two clippings about a week or two apart will achieve best results, but then the cut area must be submerged as soon after in at least 8 to 10 cm of water when water levels rise again.
Something will have to be done about the Typha growth in certain areas of Rietvlei, but any control operation will be costly and time-consuming. Using fire will help a great deal, but there are inherent dangers that must be considered. Access to the affected areas for cutting or mechanical control is not always easy and further complicates control operations.
Compiled by Niel van Wyk from various sources.
Snippets
Our chairman has volunteered to be on the Ward 4 Committee of the Blaauwberg Subcouncil. He will be keeping up with Council matters that affect the environment.
The pumping of water from the North Vlei onto the Central Pan has been successfully done this summer and the Central Pan is submerged. One must question the long term sustainability of and impact to the seasonal wetland habitat. The long awaited Estuary Rehabilitation Plan has still not begun. The CAPE Estuaries co-ordinator has indicated that the consultants should start their work in May.
Milnerton Racecourse Conservation Area - The grysbok capture and relocation, and the controlled burn of the northern half of the southern area, have been undertaken in April. Due to logistical reasons these happened in April instead of ideally March, but luckily the absence of rain in April allowed these activities to occur.
Thanks go to Chevron Refinery for sponsoring envelopes for the posted newsletter.
Friends of Rietvlei 2006-2011. All rights reserved. • Developed by Blue Cape Media • Hosted by Snowball Effect (Pty) Ltd