Restoring You Dam: A Guide to Managing Persistent Weeds
Q. Could you please identify these weeds for me and advise what product would eradiate the weeds and clean our Dam. The dam is approx 50m and approx 1m depth in the middle.
ANSWER
The health of your dam is currently compromised by a persistent combination of aquatic weeds: the emergent cumbungi reeds, the surface Potamogeton sulcatus (pondweed), and the water primrose. These species are not easily eradicated, particularly cumbungi’s ability to spread via rhizomes and its long-dormant seeds. However, with a an ongoing management plan, you can reclaim your dam and minimise future weed outbreaks.
Our Recommendations for a Healthier Dam:
Weed Control with AQ200: Your first step is a thorough treatment to suppress the existing weed growth. We recommend using AQ200 in conjunction with a wetting agent. For dense infestations, a comprehensive application is necessary: use 5 litres of AQ200 and 2 litres of wetting agent, which will treat an area of 1,250m² to 2,500m².
Application Process: Prepare your spray solution by mixing 400ml of AQ200 with 150ml of wetting agent in 100 litres of clean water. Apply this mixture with a robust spray, ensuring you drench the plants rather than creating a fine mist. Continue until all affected areas are treated. Any remaining solution can be used for targeted spot treatments.
Important Application Tip: Use clean water. Sediment can neutralize AQ200, rendering it ineffective.
Important Note on Water Usage: Please observe a 10-day withholding period after treatment. During this time, the water is unsuitable for drinking, irrigation, or use by livestock and pets.
Addressing Nutrient Imbalance with Muck Breaker: To counter the underlying issues that fuel weed growth, introduce Muck Breaker tablets. Apply 4 tablets evenly distributed every two weeks for the initial six weeks, then switch to a monthly application of 4 tablets.
Muck Breaker is designed to break down accumulated organic matter and reduce nutrient levels in the water. This directly combats the nutrient-rich environment that encourages algae blooms and perpetuates weed cycles, also contributing to improved water clarity.
Facilitating Recovery and Targeted Treatment: Around 14 days after your initial herbicide application, begin the process of physically removing the decaying weed matter. Should your dam water be particularly turbid, consider using a flocculant to help settle suspended solids. Three days post-flocculant application, re-treat any persistent weeds, paying special attention to the roots of water primrose and pondweed.
Long-Term Preventative Care with Aquatic Blue: To maintain long-term dam health and prevent future weed dominance, consider a semi-annual application of Aquatic Blue. This product works by reducing UV light penetration, which naturally slows the rate of photosynthesis in aquatic plants, offering a preventative measure against emergent and submerged weed growth.
