possible silverleaf in plum tree?

magicbastarder

is this silver leaf? it's a victoria plum; it was damaged in wind a few years ago and has two main boughs now, and the healthy leaf is from one bough and the unhealthy looking ones are from the other (and that's the bough where the damage occurred).

probably not the best time to cut that bough off, but i was reading that if it is silverleaf, i need to take off the affected section lest it spread to the whole tree - though it may well be too late for that.

standardg60

Yep looks like silverleaf alright, if you cut an affected branch there will be dark staining in the wood. Now is the perfect time to remove the bough as the disease spores are not/less active in Summer (which is why pruning of Prunus is only recommended at this time of year).

Cut back until you reach clean wood, hopefully it hasn't migrated into the trunk or other bough.

magicbastarder

cheers - i cut back to a couple of inches from the other bough, and still was getting this, so i suspect we may be getting a new tree at some point.

standardg60

Pity, you might get another couple of years out of it, burn or get rid of anything you do remove, don't leave it lying around.

magicbastarder

yep, it's going up on the roof of the shed to dry. too small to do anything with but burn it.

Jim_Hodge

https://www.boards.ie/discussion/comment/119203548#Comment_119203548

Don't leave the wood to season. Burn it ASAP before spores can be carried elsewhere. Likewise all leaves and twigs.

magicbastarder

well, RIP tree. problem now is there's a (over-vigorous) damson growing about six foot away, so i can't exactly hack away at the stump of the plum tree. do silverleaf spores stay in the soil a long time?

the damson was meant to grow to 3m IIRC, but it's easily double that height. but we never tried pruning it really as we were conscious of spreading the silverleaf to it.

standardg60

The fungus will continue to grow on the stump so cover with plastic or carpet and throw some soil on to suppress the release of spores. Not sure how long the spores survive in the ground but they've stayed viable for weeks when kept dark and cool in studies.

As for the damson chances of infection when pruned on a dry calm day in summer are pretty low, as the cut branches seal in as short as 24 hours because the sap flow is good. In contrast with little to no flow in winter that's when they become more susceptible, and nature being nature that is the time the fungus knows is best to spore!

magicbastarder

cheers, the main concern i'd have right now would be trying to remove the stump, if i hacked at roots i could spread the disease to the roots of the damson tree - as mentioned, it's maybe six foot away so the roots probably overlap.

pruning the damson is going to be an issue regardless, i reckon we were sold a mislabelled rootstock, so it will be an ongoing chore to keep it to the size we'd expected.