Spraying rhododendron.

[bulltaco]

Hi,

I've scoured around but can't find a definitive answer about nozzles and pressures for spraying rhoddie regrowth after cutting.

 

Can anybody advise or point me towards info on this please?.

 

Using a CP15 sprayer, roundup pro @2% and mixture b @2%, whats the best nozzle/pressure combination? - fan/cone, 1bar/3bar?.

[bulltaco]

One of my lads was watching a contractor the other day using a green fan nozzle with Roundup Pro at 1 litre to 10 litres water and 3 bar pressure, which seems a bit much?.

[Big Bolt]

I know it all depends on the amount to do, but i mix 50/50 plus wallpaper paste and dye and paint it on 99% kill rate so i dont get much regrowth.I have never rated roundup any good for regrowth on rody , just wait till it gets a bit bigger and paste it again

Edited August 25, 2010 by Big Bolt

[Charlieh]

FC current best practise for foliar sprayging is 20% glyphosate mix and 2% mixture b

 

here is an interesting pdf, it doesnt answer your specific questions but i found it of interest for this area of work http://www.forestry.gov.uk/pdf/Argyll_Bute_rhododendron_2008_best_practice.pdf/$FILE/Argyll_Bute_rhododendron_2008_best_practice.pdf

[porky]

Roundup should be 10%, wetting agent 2%, yellow cone is probably the best nozzle to use.

[porky]

Just read that FC link and it does say 2% Roundup for foliar spray

[Charlieh]

yep sorry ignore me, still on the first coffee of the day, its 20% for stump treatment

 

I have only done stump treatment on fresh cuts, never used it for foliar application, Has anyone used dyes in tank mixtures, to make treated stumps easier to spot, its not a route i have gone down but would be interested in identifying suitable dyes to use

[porky]

I always put some red dye in the mix when doing stumps as it makes it easier to see where you have been. It fades after few days.

Tried it on foilar spraying but it doesnt work very well.

[bulltaco]

Thanks for the input all.

I hadn't seen that FC practice note, very interesting. Didn't know that you're only allowed to spray regrowth under 1.3m.

I too was thinking a yellow full cone nozzle with a 1 bar FCV would be about right.

Cheers.

[porky]

. Didn't know that you're only allowed to spray regrowth under 1.3m.

 

Thats a H&S issue, you dont want to get Roundup in your face!

 

If you end up spraying at 2% Roundup solution can you let us know whether it was succesful. It would be good to know it works in practice. The less you need to use the better.