It was a disastrous year for me and most of my customers. I took two sets of samples to my cooperative hort agent and she along with assistants could not find any evidence of the thrips that might have caused all the damage which basically looks exactly like thrips damage. photo of thrips damage on nectarine at DuckDuckGo
Also, I use the neonic Assail in my spring sprays which is supposed to help control it. The damage began appearing after the first of two such sprays.
The master degree horticulturist still suggested it was probably thrips, but she is no expert on fruit tree pests. She was just following “if it quacks like a duck” logic.
I still believe it may all have been from ovule damage during mid March’s sudden temp nose dive. It certainly destroyed the ovules of several trees without damaging male flower parts noticably.
Yeah, but it didn’t destroy your entire crop. Only my two earliest whites gave me a few, but almost nothing. Fungicide would not halt the rot. That suggests it is from the inside to me.
After further review, the dwarf red nectarine that ripened late june is Necta Zee. I got it confused with garden delight, which is just now turning from green to yellow.
Zephyr nectarine, more than a pound. My best late season, white nectarine. Excellent low acid flavor. Some years it tops Arctic Jay, others Arctic Jay wins.
Big white nectarines usually split and rot here in downstate NY. I’m guessing you live on top of a hill with lots of sun and breezes in a wide open space. I think it is important when discussing varietal merit that ones site be described. Zone and region are only half the story. Sun and breeze exposure along with soil texture are also important. There is not much in the literature about this because commercial orchards are usually in wide open spaces, often on the sides or tops of rolling hills. Old fashioned guidelines like, “The Apples of New York”, at least sometimes discussed soil texture
My site is perfect for providing information about crack and rot resistance. As the words of the song say, if it can make it here it can make it anywhere. I’m in a hollow surrounded by thick walls of tall forest trees on all sides. About 3 acres have been cut out in the middle of this, so I get pretty decent sun, but the air doesn’t move much on days without strong breezes and dew lasts a long time on the fruit. My one advantage is that on most parts of my orchard the soil is well drained with a somewhat sandy silt on top.
As compared to what?.. probably not my site. The difference in plums and nects cracking and not cracking can be a very small number. Do you notice any increase in problem with trees with more eastern shade.
I have sites I manage with a lot of eastern shade that don’t have a lot of black knot or brown rot problem, apparently becuase of very good air circulation.
Compared to my old orchard in Delaware. Growing conditions and climate are not very different between here and there. Main differences are winter minimum temperatures, spring freezes, and slightly shorter season. Also, here I am in a rural heavily forested area, while there was a suburban setting with much less trees. The result is that pest pressures here (all pests, except squirrels) are much higher.
All my plums are intentionally planted in the area with good eastern exposure. As far as brown rot, it was all over the place, I think it was intensified by rain, more than dew (although due is certainly a contributing factor), due to splashing, and by varietal susceptibility. I lost almost whole crops on certain trees, while others suffered 10-30% loss. One thing that I should do better next year is removing vigorous, upward shoots in the middle of my open center, as they block sun, negatively impacting fruit development and quality and also delay drying and hence exacerbating Brown Rot.
This year I believe the cause for my much more than normal brown rot is the result of ovule injury from that March 19th deep dive. I already was leaning on that being the reason for all the deformed nectarines I saw on mine and other sites. Today I learned that it is general knowledge that this damage does occur frequently enough to be known in the commercial production world.
This explains why I have so much trouble in spite of being on it with fungicide apps. The rot starts internally and can’t be touched if the ovules are injured in a certain way.
On warmer sites nectarines were OK. Sometimes generally warmer sites can bring the opposite results if we have a cold event on a windy night. Then the warmer sites can have less hardened off buds but the wind brings them the same temps. There are so many variables it can make my head spin.
It is the brown rot factor that really made me decide my problem this year was most likely that freeze and not thrips. It took me a long time to figure that obvious answer out, - that is the connection between deformed nectarines and nicely shaped peaches that still tended to rot, but I won’t feel certain until next year. If I don’t find thrips at bloom next season I will be pretty confident of the deduction.
@alan
What about humidity? I get a lot of airflow. And try to keep the interiors of my trees ‘sunny’. But the air here, for most of the summer, is 90% water! An exaggeration, of course - but it is horribly muggy here in the summer. Even if there is not much rain - wouldn’t humidity create/cause problems with fungal and rot problems?
Another question. What causes all the rot around the pits of otherwise rather spot free fruit? I had a lot of that in my peaches and nectarines - and some plums. Is that also brown rot? Does that start early - in the flowering stage? And . . . is it more prevalent in freestone varieties than clings? - thanks
Did you also get a sudden dive in temps on Mar 19th. Read comments directly above.
I’ve been suspicious of the Mar. 19th deep dive since I saw most of my nectarines flower beautifully but setting almost no fruit and fruit that set was deformed. All through the season, brown rot has not been adequately controllable with the best fungicides even on well formed looking peaches- and forget about the deformed nects. Only Silver Gem and Carene gave me any crop at all. .
I decided to ask Chat and it agrees with my somewhat educated hunch.
My question to Chat, “Can a very early spring deep freeze damage the ovules of peach flower buds in a way that causes damage to later developing fruit such as deformities for the fruit or interior damage that leads to brown rot?”
ChatGPT said:
Yes, a very early spring deep freeze can indeed damage the ovules of peach flower buds, leading to issues in the later development of fruit. When a deep freeze occurs during the early stages of flower bud development, it can cause several types of damage:
Ovule Damage: The ovules within the flower buds are very sensitive to freezing temperatures, particularly during the swelling and blooming stages. If the ovules are damaged, the fertilization process may be impaired, leading to poor fruit set, deformities, or aborted fruit.
Fruit Deformities: If the fruit does develop despite ovule damage, it may show physical deformities such as misshapen fruit or scarring. The development of the fruit could be uneven, leading to irregular shapes.
Internal Damage: Freeze damage can also cause internal cellular damage to the developing fruit. This can weaken the fruit’s structure, making it more susceptible to diseases like brown rot. The compromised tissue provides an entry point for fungal pathogens, which can cause the fruit to decay from the inside out.
Increased Susceptibility to Brown Rot: Brown rot is a fungal disease that thrives in damaged or stressed fruit. Freeze-damaged peaches may have microscopic cracks or weakened tissue, creating ideal conditions for brown rot to take hold. The disease can start from these damaged areas and rapidly spread throughout the fruit.
I probably misremembered the date. That it dropped to 19 here and 23 there tells you a lot about your site compared to mine. You are in a strip of “banana belt”, apparently and that difference can be a world of difference to fruit. .
We got about 20 nectarines from our Harko nectarine, But they were all small and thrip damaged.
This is the first year it has fruited.
Also, they were too soft when we picked them because they were so small, we didn’t believe they could possibly be ready, but I probably should’ve checked them because they were such a pretty dark red color.
None of that stopped them from being sweet and juicy, so I expect great things from our Harko nectarine in the future, although there is a struggle with peach leaf curl for sure and late spring frost, and now apparently thrips.
We had bagged the fruit and didn’t realize the damage was already done at the bloom stage.
