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View Full Version : Viscum Album erradication help.


Stevie Ray
04-13-2005, 02:13 PM
I have a client with a severe case of Viscum (Mistletoe) in a walnut tree. I have heard (without any proof thus far) there are some products available which act as systemics. Is there any truth to this? Other than cutting it out, are there any other methods. Possibly topical fungicides if the systemic is a myth? Thank you in advance for your assistance.

Garth
04-18-2005, 01:41 PM
I have a client with a severe case of Viscum (Mistletoe) in a walnut tree. I have heard (without any proof thus far) there are some products available which act as systemics. Is there any truth to this? Other than cutting it out, are there any other methods. Possibly topical fungicides if the systemic is a myth? Thank you in advance for your assistance.

To my knowledge Viscum is a parasitic plant that will not be treatable with systemics or fungicides. As it form the symbiotic relationship with the host, it absorbs nutrients from the xylem it has tapped into. Therefore, systemics will protect the mistletoe in the same way as the host. Manual removal is the most effective way of removing it.
Of note, there has been some prominent physicians studying the effects of mistletoe on cancers and HIV. Some of the reports I have read have been very positive particularly from a group of German and Canadian scientists.
Take into account that when you remove the plant you'll have to seal the wound to prevent anything getting into the tree, and poisons will likely affect the tree as well as the target.
Prune out the branch of the infested tree at least 1 foot below where the mistletoe is attached. If it has attached itself to the trunk or a branch to large to prune, cut flush with the surface. It will slow the growth of the parasite but it will grow back. To stop it from growing back eliminate the light. Wrapping black polyethylene plastic over the wound and wrapping it with flexible tape helps. There is some control using plant growth regulators with ethephon.