Bad Weekend

[FB.]

The long drought has caused me to water some of my young half-standard fruit trees, to ensure their continuing establishment.
I took a walk around them for a close inspection today and found six of them dead or dying.

One Discovery apple tree on MM111 rootstock, had died from presumed drought stress, despite regular watering.

One Ardcairn Russet on M25 rootstock, dying from a girdling canker at ground level, presumably due to damp as a result of watering.

One Jumbo on MM106 rootstock dying from drought stress, despite regular watering.

Two Catillac pear trees on Pyrus rootstocks had numerous small cankers at the base of the trunk, just above the graft line, meaning that girdling was inescapable, even if I tried to cut out the cankers.

One Hessle pear tree had a bad canker threatening to girdle the tree at ground level, presumably due to damp ground as a result of watering.

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If I don't water them enough, they die of drought stress.

If I water them too much, they get near-ground cankers as a result of persistently damp ground, which then girdle the trunk and block sapflow, killing the top of the tree.

This "spray-free" fruit growing (especially on a poor soil like mine) sometimes throws just one or two too many problems for the poor young trees to cope with.

What a disaster.

I need a cold beer.

[rana]

Would the installation of watering pipes leading down into the soil help? The surface soil would remain relatively dry but the roots could still get water. Also how do commercial growers manage in California where summer drought is normal?

[Jeanied]

I think the commercial fruit growers spray their crops from above with the huge oscillating water cannon type things- which would keep the trunk of the tree dryer and just moisten the soil around the edge of the canopy.

[Glutton4...]

Hi FB, have you tried ring irrigation?

When planting semi-mature trees, and we used to put a ring of perforated pipe round the root-ball, just above halfway down the root-ball. There was a small length of pipe left sticking out, so the hose could go in, and the water went to the root and surrounding soil, instead of the surface, and encouraged the tree to put downward roots instead of near the surface. We used to wet the surface too, them mulch it. Success rate was very high.

Forgive me if I'm telling you something you already know!

[FB.]

Thanks for the replies, folks.

Since I started the topic, I have lost a few others on MM106 rootstock.

I am now suspecting that since most of the trees are relatively young (5-10 years), the rootstock portion of the trunk hadn't fully matured and hardened-off, which then allowed the long, cold winter to damage the bark, followed by entry of canker spores as a result of the ground being frozn and then cold and damp.

Apple trees affected are especially on M25 rootstock, with some on MM106.
The variety grafted to the rootstock didn't seem to make any difference.
No trees on MM111, M26 or M9 rootstock were affected, but these rootstocks are often considered to be more tolerant to deep freezes.

A useful lesson, perhaps, for Northern growers.
My suggestion: go with M26 for apple bushes around 8ft and go with MM111 for medium-sized apple trees around 12ft. Of course, soil, climate and variety will have some effect on the final size.