[moonbug33]

Hope I am posting this in right section.......I have a fairly long border hedge about 20 metres or so full of rhododendron that has taken over. The hedge has a few holly tress that I want to keep and develop. I have started cutting some of the plants....some are more like trees and then I will treat the stumps with "roundup."
Is this the right approach or should I be doing this another way?

[walltoall]

You got a job on your hands alright. Kerry is moidered with rhodendron which although it looks wonderful for about two weeks in June is otherwise a totally useless species. I found this site for you, which I found quite fascinating ......

http://www.plural.freeuk.com/bonskeid/conserve/rhodo.html

Basically it is as you suggest, slash and burn and Roundup plus a sticky medium. Note that they cut back to short stumps but waited for a year or two for new growth to appear before applying the Roundup. This makes sense because the Roundup is best taken up by leaf growth, travels down into the root system and kills. Painting cut stumps with it won't work for you.

The root system for rhodendron is kinda like the rhisome method used by your scutch grass, which is why it is hard to eradicate.

Best of luck

[moonbug33]

Thanks for that..............I was also reading how they use a similar approach in The Killarney National Park, thankfully I only have a long ditch type hedge to deal with. I really want to sort this out this year before it becomes a true monster.

[michael brenock]

roundup is not much use in trying to kill off rhodos. Cut the stems as low down as possible, bore a few half inch holes in them 6-8 inches deep and fill with Nitrogen fertiliser.
michael brenock horticultural advisor(retired)

[moonbug33]

Thanks.....that sounds like like a good approach...... I will try that.