I was watching a college station with a garden teacher and he was saying that for some blights you need to clean your lopers or pruners off between each limb cut if you don't want to transfer viruses. So that is worst case scenario cleaning between branches of same plant. He said a rubbing alcohol solution was to be sprayed on your cutting tool. I don't remember if he said it was mixed with water. I just remember him saying 10% but that could be the nature of the alcohol itself. Hope that helped a tad.

Good folk of different persuasions here question/debate how/whether to do this. But it doesn't hurt, so far as I know, to disinfect as you go, and I do it myself.

I think three I've tried are alcohol, chlorine bleach, and Pine-Sol. Alcohol should be cut to 70%; chlorox type bleaches are generally effective if you can smell them, and Pine-Sol has the instructions on the bottle. Alcohol is drying, chlorox is corrosive to tools, and I don't know of any ill affects of Pine Sol other than odor, so that's what I've been using. But I still rinse, dry and clean and lubricate my nippers after hitting them with any of the three.

I haven't given much thought to shovels and trowels and such. Maybe I should, but that seems to me a case where environment matters more than technique, whereas things that happen above ground can be too easily hit by any and every caprice and ya gotta watch 'em every step of the way!

Good luck,

M

I use one of those mini butane torches, about the size of a deodorant stick. It starts instantly when you click the trigger, kills all viruses and bacteria, and doesn't rust or corrode my tools. A quick pass burns the fuzz off wooly aphids so I can kill them with oil soap spray.

I use Lysol Disinfectant Spray to disinfect my pruning tools. At least one study I saw (maybe more, can't remember) claimed it was the least corrosive and one of the most effective treatments for this. It is very convenient (even for a chainsaw chain), and I haven't noticed any damage (corrosion or rust) at all to any of my tools. I don't always use it, but I do use it where disease is suspected or when working with sensitive plants. I also carry alcohol wipes in my truck to clean "gunky stuff" off my pruners as needed.

I don't think there's a single commercial orchard that uses disinfectant as part of normal pruning regimen except maybe for pruning out fire blight and black-knot. I never use it and have never regretted it.

When I prune out black-knot, I hit the wounds with chlorathalonil these days. It is possible that between cuts there'd be some value in disinfecting. Return infections always seem to be at sites of gall removal, however, even when there are other pruning cuts made at the same time on any given plum tree. Otherwise galls appear at points where there are no wounds. If I saw infection at the clean cuts I would begin disinfecting in earnest.

I tend to ignore recommendations that are passed on without the scrutiny of actual research. I'd be very interested to see some research on this issue- even as it applies to FB shoot removal.

If I do decide to start using disinfectant I'll run with the Lysal suggestion. Bleach had always been the material I've seen suggested, but I can see how that might be hard on metal.

I leave my tools on a bench in an open porch. Allows ordinary sunlight to disinfect.

The Bottom Line
 Choose a disinfectant that is effective, readily available and affordable, relatively safe to
handle, and wonÂt harm your tools or clothing. Many household cleaners fit this description.
 Be sure to clean tools of dirt, debris, etc. before disinfecting.
 After dipping your pruning tools, be sure to wipe away excess disinfectant to avoid injuring
the next plant.
 A longer soaking may be needed for pruning surfaces that are not smooth.
 Like pruners, increment borers should always be sterilized before and after use.
 Never use disinfectants on pruning wounds; they are phytotoxic and cause more harm than
good

Here is a link that might be useful: The Myth of Cloroxed Clippers