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Apple Trees Endangered


hazelm

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Sounds like, whatever they figure out, they're not gunna be able to pin this one on global warming, eh?:

 

 

Weather-related stress—drought and severe cold—could be an underlying cause, researchers reported this month in PLOS ONE. Early freezes are becoming more common across the eastern United States, for example. But that doesn't appear to be the whole story....

 

 

One common symptom in trees struck by rapid decline is dead tissue at the graft union, the part of the trunk where the fruit-bearing budwood of an apple variety is joined to hardy rootstock to create new trees. The union is vulnerable to late-season freezes because the tissue is the last to go dormant....

 

A team led by plant pathologist Awais Khan of Cornell found dead tissue just below the graft union in trees from an affected orchard in New York. They suspect the cause was the extremely cold winter of 2014–15, which was followed by a drought.

 

 

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Sounds like, whatever they figure out, they're not gunna be able to pin this one on global warming, eh?:

Nice to have a change, yes.   There is a lot of this going on.  A recent news item said exhaust from cars is killing city trees.  A friend in Texas says oak trees in their area are in bad shape.  Do you suppose the trees decided they didn't much care for this overly-developed planet.

 

Hmmm.  A friend and I recently read a three-volume sci-fi that touched on this "over-developed" planet and its hazards.  Can't recall the author.  Are we onto something? 

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This sounds like an ideal environment for the spread of a fungal agent.  It appears that sustainable horticultural practices may have been abandoned in favor of maximizing production.

 

Modern apple farming methods could also be a factor. Rapid decline is most common in dense orchards, which are increasingly planted because they are efficient to manage. Instead of about 250 trees per hectare, high-density orchards can have 1200 or more. Tightly packed trees must compete for nutrition and moisture. They also have shallow roots, which make them easier to trellis but more vulnerable to drought. "I'm not criticizing the system," Khan says, "but it's not robust for these kinds of fluctuations."

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Nice to have a change, yes.   There is a lot of this going on.  A recent news item said exhaust from cars is killing city trees.  A friend in Texas says oak trees in their area are in bad shape.  Do you suppose the trees decided they didn't much care for this overly-developed planet.

 

Hmmm.  A friend and I recently read a three-volume sci-fi that touched on this "over-developed" planet and its hazards.  Can't recall the author.  Are we onto something? 

 

Oaks are not particularly tolerant of air pollution, specifically particulate emissions from diesel engines.  Sycamores tend to do much better in cities and are recommended by arborists.

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We have an infestation of ash tree borers.  When the ash trees are not available, the borers choose oak trees.  Now our oaks  are being attacked.  Add to that that a certain frisky little resident squirrel likes to sit up there and chew off twigs so he can feast on the borers or their eggs.  He then litters the ground with the twigs.  The oak looks sick.  The paunchy little squirrel looks well fed.  At least somebody is eating.

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For all practical purposes, the American Elm is essentially extinct.  In nearly 6 decades I have never seen a single specimen, healthy or ill.  Some genetic variants have shown some resistance to the fungus so far but only time will tell, and even then I doubt the elm will ever return to widespread cultivation.  I was surprised to read that the fungus also infects Zelkova, which is a relative of the Elm.  Zelkova Serrata has been fairly popular with commercial landscapers here in the southeast US but this specific cultivar is highly resistant to the fungus.

 

Ten resistant American elm U. americana cultivars are now in commerce in North America, but only two ('Princeton' and 'Valley Forge') are currently available in Europe. No cultivar is "immune" to DED; even highly resistant cultivars can become infected, particularly if already stressed by drought or other environmental conditions where the disease prevalence is high. With the exception of 'Princeton', no trees have yet been grown to maturity. Trees cannot be said to be mature until they have reached an age of 60 years.

 

https://en.wikipedia.org/wiki/Dutch_elm_disease

https://en.wikipedia.org/wiki/Zelkova_serrata

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I understand squirrel tastes nice, have you a gun :) and a cooking pot.

 

Is there a problem with infestation due to foreign immigrants your apple trees aren't tolerant to. The American Chestnut was more or less irradicated due to an imported fungus from the far east, which they had no tolerance to.  If it is perhaps building a wall will stop the infestation of immigrant species.

 

I have shot hundreds of squirrels in the last 30+ years and have never once been tempted to eat one of the nasty flea ridden vermin.  Remember that they are just rats with bushy tails.  I am fortunate to have a diligent clean-up squad on staff* so I never have to touch them.

 

*Hawks, owls, foxes, raccoons, possums, etc... 

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It looks like they may have the culprit in their sights.  Application of an elastic sealant at the graft might help keep the beetles away without resorting to insecticides and fungicides

 

In hard-hit North Carolina, researchers have found ambrosia beetles infesting the graft union of dying trees. These stubby insects burrow into weakened trees and cultivate fungus for their larvae to eat. Those fungi or stowaway fungi might harm the trees, an idea that Sara Villani, a plant pathologist at North Carolina State University in Mills River, and colleagues, will start to test in June. Researchers there will also test way of boosting the trees' immune systems.

Modern apple farming methods could also be a factor. Rapid decline is most common in dense orchards, which are increasingly planted because they are efficient to manage. Instead of about 250 trees per hectare, high-density orchards can have 1200 or more. Tightly packed trees must compete for nutrition and moisture. They also have shallow roots, which make them easier to trellis but more vulnerable to drought. "I'm not criticizing the system," Khan says, "but it's not robust for these kinds of fluctuations."

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Sounds like, whatever they figure out, they're not gunna be able to pin this one on global warming, eh?:

 

The winter of 2018/2019 was exceptionally mild here in the Carolinas and the fruit trees are in full bloom.  This would be the worst possible time for a late freeze to damage the peach and apple crops although the strawberries and cole crops should do fine.  It is time to plant soybean, corn, and cotton and to start tomato plants in the greenhouse. 

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The winter of 2018/2019 was exceptionally mild here in the Carolinas and the fruit trees are in full bloom.  This would be the worst possible time for a late freeze to damage the peach and apple crops although the strawberries and cole crops should do fine.  It is time to plant soybean, corn, and cotton and to start tomato plants in the greenhouse. 

Cole crops?  Cruciferos vegetables?  Same thing?  Thanks for the new term.  Never heard that before. 

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"Cole" is easier to spell than Cruciferous, and it is the origin of the name Cole Slaw.

 

"Cole" refers to any of various cool season plants belonging to the Cruciferae, also known as the Brassicaceae oleracae family, such as cabbage, broccoli, cauliflower, collards, Brussels sprouts, kale, kohlrabi, mustard, turnips and watercress. The word cole actually means 'stem'. Many of the vegetables in this category allow you to eat all or a portion of the stem.

 

http://normsgreenhouseandnursery.com/Cole%20Crops.htm

 

 

Sorry, I couldn't get rid of the green background on the cut-n-paste and I wasn't about to retype it.

Edited by fahrquad
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I am debating putting a few tomato plants at the side door.  The spot is in full sun most of the day, although I will either have to drag a hose around or haul a water bucket.  I have way too many big trees in the back yard, and although the shade is nice, it leaves me nowhere to plant a decent garden. Maybe I can squeeze in a few Okra plants either with the tomatoes or in with the blueberry bushes.  This might be a good time to re-establish my fish tank since I can dump the dirty water on the plants.

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"Cole" is easier to spell than Cruciferous, and it is the origin of the name Cole Slaw.

 

"Cole" refers to any of various cool season plants belonging to the Cruciferae, also known as the Brassicaceae oleracae family, such as cabbage, broccoli, cauliflower, collards, Brussels sprouts, kale, kohlrabi, mustard, turnips and watercress. The word cole actually means 'stem'. Many of the vegetables in this category allow you to eat all or a portion of the stem.

 

http://normsgreenhouseandnursery.com/Cole%20Crops.htm

 

 

Sorry, I couldn't get rid of the green background on the cut-n-paste and I wasn't about to retype it.

Or, just type "cole" = "cruciferous" .   Different  terms in different parts of the country.  It's a common happening. :-)

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After looking at the list of Cole Crops Cruciferous Vegetables I suddenly have a craving for Chinese Food.

 

Horseradish Armoracia rusticana
Land cress Barbarea verna
Ethiopian mustard Brassica carinata
Kale Brassica oleracea Acephala group
Collard greens Brassica oleracea Acephala group
Chinese broccoli (gai-lan / jie lan) Also called Broccolini Brassica oleracea Alboglabra group
Cabbage Brassica oleracea Capitata group
Savoy cabbage Brassica oleracea Savoy Cabbage group
Brussels sprouts Brassica oleracea Gemmifera group
Kohlrabi Brassica oleracea Gongylodes group
Broccoli Brassica oleracea Italica group
Broccoflower Brassica oleracea Italica group × Botrytis group
Broccoli romanesco Brassica oleracea Botrytis group / Italica group
Cauliflower Brassica oleracea Botrytis group
Wild broccoli Brassica oleracea Oleracea group
Bok choy Brassica rapa chinensis
Komatsuna Brassica rapa pervidis or komatsuna
Mizuna Brassica rapa nipposinica
Rapini (broccoli rabe) Brassica rapa parachinensis
Choy sum (Flowering cabbage) Brassica rapa parachinensis
Chinese cabbage, napa cabbage Brassica rapa pekinensis
Turnip root; greens Brassica rapa rapifera
Rutabaga (swede) Brassica napus napobrassica
Siberian kale Brassica napus pabularia
Canola/rapeseed Brassica rapa/napus oleifera
Wrapped heart mustard cabbage Brassica juncea rugosa
Mustard seeds, brown; greens Brassica juncea
White mustard seeds Brassica (or Sinapis) hirta
Black mustard seeds Brassica nigra
Tatsoi Brassica rosularis
Wild arugula Diplotaxis tenuifolia
Arugula (rocket) Eruca vesicaria
Field pepperweed Lepidium campestre
Maca Lepidium meyenii
Garden cress Lepidium sativum
Watercress Nasturtium officinale
Radish Raphanus sativus
Daikon Raphanus sativus longipinnatus
Wasabi Wasabia japonica
 
Edited by fahrquad
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That's quite a collection, Fahrquad.  I'll eat the turnips - boiled to mush and buttered - if you'll eat the broccoli.  Those two - and maybe others - should not be in the same family, genus or kitchen.  Good morning.  Hazel

 

Cruciferous vegetables are more prevalent in our diets than you think. Steamed broccoli is great with melted cheddar cheese, collards with ham is a traditional southern dish, steamed cauliflower with a little heavy cream pulverized in a food processor makes a passable low-carb substitute for mashed potatoes for Atkins Diet followers, bok choy is used heavily in Chinese food, arugula is in your salad mix and so is sliced radish, wasabi is a common condiment for Japanese food that should never be mistaken for guacamole, horseradish sauce goes good with roast beast, mustard seeds are ground to make the yellow stuff on your hot dog, canola oil was used to fry something you ate today with the previously mentioned cole slaw on the side, pickled red cabbage makes a nice side to pork chops, sauerkraut is served on hot dogs in some parts of the country, and pickled cabbage (red or white) is served with many German dishes.

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