Dead plum tree

  • 5 Replies
  • 8947 Views
*

JTh

  • Hero Member
    • Email
Dead plum tree
« on: July 28, 2016, 04:17:41 PM »
Some friends have a place on a nearby island here in Halkidiki. They have a plum tree which was full of plums; this summer, suddenly, the tree died, they say it looked OK one day, the next day it was dead, with all the fruit still hanging there. Does anybody have an idea what could lead to this sudden death?
« Last Edit: September 11, 2016, 01:47:03 PM by JTh »
Retired veterinary surgeon by training with a PhD in parasitology,  but worked as a virologist since 1992.
Member of the MGS  since 2004. Gardening in Oslo and to a limited extent in Halkidiki, Greece.

*

MikeHardman

  • Hero Member
    • www.mikehardman.com
Re: Dead plum tree
« Reply #1 on: September 10, 2016, 10:23:26 PM »
Really sudden plant death can be caused by gas - either a leak from a man-made gas supply or a natural emission (mainly in volcanic terrain). Such a gas leak would probably also kill adjacent plants. If only the plum tree is affected, and there are other plants adjacent, gas won't be the cause.

But perceived sudden death in woody plants can also be the last stage of a longer-established problem. A canker, for instance, can gradually work its way round the trunk, and the tree can get-by surprisingly well until the canker completes the girdling. Initially, that will stop the flow of sap to the roots, but then the roots stop working and the supply to the leaves (and any fruit) ceases. Various fungi and other pathogens can cause similar effects, with relatively sudden decline and death eg. Armillaria (honey fungus), and Phytophthora.

Plums are susceptible to more diseases than most trees (a feeling; I don't have data to back that up). Silver leaf (Chondrostereum purpureum), for instance, goes for Prunus (but that's unlikely to be the agent in your case, as it usually kills a tree a branch at a time).

It would be worthwhile prising up bark at soil level and excavating the roots a bit, looking for signs of fungal bodies. If some are evident, they may be the causative agent. They could also be secondary, but it might be a bit soon for secondary infections to establish and get to a recognizable fruiting stage. It is important to check for fungal pathogens, as they could spread to other trees or shrubs.

Some refs:
- http://www.petercoppin.com/factsheets/pests/plantdie.pdf
- http://www.cotswoldtreesurgeons.co.uk/sudden-tree-death
- https://ask.extension.org/questions/305929

Mike
Mike
Geologist by Uni training, IT consultant, Referee for Viola for Botanical Society of the British Isles, commissioned author and photographer on Viola for RHS (Enc. of Perennials, The Garden, The Plantsman).
I garden near Polis, Cyprus, 100m alt., on marl, but have gardened mainly in S.England

*

JTh

  • Hero Member
    • Email
Re: Dead plum tree
« Reply #2 on: September 11, 2016, 02:02:03 PM »
Thank you, Mike, I suspect the tree had suffered for a while before they discovered that it was dead. It is probably a good idea to remove the tree as soon as possible and burn it, after having checked for the signs you mentioned.

We had a plum tree here in Norway for quite a few years, it was always full of of plums. One day we a had a storm when the plums were ready to be harvested; the whole tree just fell over and we discovered there  was hardly any root at all, it was a wonder it had been alive that long. It was very easy to harvest the plums that year.
« Last Edit: September 11, 2016, 02:32:51 PM by JTh »
Retired veterinary surgeon by training with a PhD in parasitology,  but worked as a virologist since 1992.
Member of the MGS  since 2004. Gardening in Oslo and to a limited extent in Halkidiki, Greece.

*

MikeHardman

  • Hero Member
    • www.mikehardman.com
Re: Dead plum tree
« Reply #3 on: September 11, 2016, 02:16:49 PM »
You're welcome Jorun.

Easy pickings - :)
At olive picking time, it is common practice here to prune the trees at the same time (if necessary), and to do so before picking the fruit from those branches. I do it myself now.

Large trees must surely make noise by virtue of the rapid rate of sap flow in the trunk on a hot summer day. I've seen photos of a big oak by a canal which was almost girdled by a barge chain that had been wearing away at it for years. How much quicker must the flow be in the remaining good part?
That sort of thing makes me wonder if there is knowledge and diagnostics to be had from putting a stethoscope to a tree and listening to the sounds of the sap flowing, timber creaking, etc. 
Maybe your Norwegian plum tree would have sounded sickly before it fell...

Mike
Mike
Geologist by Uni training, IT consultant, Referee for Viola for Botanical Society of the British Isles, commissioned author and photographer on Viola for RHS (Enc. of Perennials, The Garden, The Plantsman).
I garden near Polis, Cyprus, 100m alt., on marl, but have gardened mainly in S.England

*

JTh

  • Hero Member
    • Email
Re: Dead plum tree
« Reply #4 on: September 11, 2016, 02:36:11 PM »
We have a new plum tree, it is loaded with plums which are ripe now. Maybe I should get my stethoscope out to check the sound of the sap flowing.
Retired veterinary surgeon by training with a PhD in parasitology,  but worked as a virologist since 1992.
Member of the MGS  since 2004. Gardening in Oslo and to a limited extent in Halkidiki, Greece.

*

Fleur Pavlidis

  • Global Moderator
  • Hero Member
Re: Dead plum tree
« Reply #5 on: September 13, 2016, 09:20:01 AM »
Just don't do it when there are any passers-by to see you!
MGS member, Greece. I garden in Attica, Greece and Mt Goulinas (450m) Central Greece