Planting new trees after diseased tree taken out?

[silverfork]

I've got a very diseased Pear tree in my garden, which I've finally decided to take down, after repeated attempts to revive it, by pruning, feeding etc. It's quite old, and gnarly, with split and damaged bark. It bears fruit which look OK to begin with, then don't swell much before they shrivel up into little black pear effigies. I've never had a single fruit from it in 4 years. I've got a bare root Doyenne du Comice pear (from Lidl this week) and an Apple (in a container at the mo) to replace the old tree. Is it OK to plant them near the site of the old tree, but not in the same soil? Are the new trees likely to get the same disease, and what is it? It doesn't seem like the pictures of scab I've found. The bark looks like Canker (but I thought that was for plums etc). I have tried to research this on the net, so any wisdom gratefully recieved. I can't put the new trees far from the old one, as my garden isn't that big.

[snuffer]

I had an old pear tree that had (I think) canker. Sounds like yours; split bark, withering fruits etc. When I replaced it I dug it up being careful to ensure that I got all the old root out. I then removed some of the soil and replaced it with plenty of compost mixed in with new soil taken from another part of the garden. A new pear tree was then planted in almost exactly the same spot as the old one. It has now been in for about three years and up to now I have had no problems.

Don't know if the text books reccomend planting in the same place but so far so good.

[FB.]

For what it's worth, I'm wondering if your pear tree has FIREBLIGHT.
If it is, you have a very serious problem. It attacks pear trees and will also attack many apple trees. Young trees with blossom are most at risk and can be killed in a matter of weeks with the right conditions. Young wood (less than 5yrs old) is reported to be especially easily infected.

Do some research on Fireblight and see if it resembles your problem.
If it is confirmed, you will have a lot of trouble controlling it.
There are some fireblight resistant fruits around (I don't think there are many resistant pears), so all is not lost, but you may need to get them from specialist nurseries.
Looking through my notes:
Some apple varieties with resistance:
Blenheim Orange - virtually immune
Bramley - high resistance
Liberty - high resistance
Norfolk Beefing - high resistance
Golden Delicious - moderate resistance
Spartan - moderate resistance
Kidd's Orange Red - moderate resistance

You will also need a FB resistant rootstock:
M7: moderate resistance
MM111: moderate resistance
MM106: some resistance

The pear variety "Seckle" has reported FB resistance. Unfortunately, few pear rootstocks have much resistance and the FB may kill the roots of a young tree in a matter of a few weeks.


If you exclude FB as a problem, then carry on as follows:

If possible, plant the new trees away from the root spread of the old tree. The old tree roots probably extend a bit further than the visible part of the tree.
If that's not possible, you should dig a large hole; down to the subsoil (1-2ft deep) and wide enough to accomodate twice the root spread of the new tree (3-4ft).
Replace the old soil with new soil and compost (take some topsoil from somewhere else in your garden; away from the old tree).

The apple ought to be much less at risk of problems than your pear. Comice is a strong grower, so it's vigour should help to get it established even if there are some residual disease problems from the old tree.

[silverfork]

Wow. Thanks for the heads up on Fire blight, FB. I don't think it is that, but it's hard to tell now all the leaves are gone, so I'm going to contact DEFRA to rule it out.

[silverfork]

Fire Blight

Thanks for the tip. After researching Fire blight on the net and finding a DEFRA leaflet, I rang Defra up and eventually spoke to a very helpful chap. The verdict was its not Fire blight, but if there was any real doubt he would have sent me a testing kit to be sure. As it is, he thought the canker had taken hold as the tree was dying anyway. He thought replanting with apple and pear trees should be fine, as they would be healthy trees, and the canker shouldn't be an issue. He was keen to point out that I should rule out Honey fungus when taking out the old tree though.