Skip to Content.
Sympa Menu

nafex - Re: [NAFEX] Copper spray timing when plants are not synchronized

nafex@lists.ibiblio.org

Subject: North American Fruit Explorers mailing list at ibiblio

List archive

Chronological Thread  
  • From: <dmnorton@royaloakfarmorchard.com>
  • To: "North American Fruit Explorers" <nafex@lists.ibiblio.org>
  • Subject: Re: [NAFEX] Copper spray timing when plants are not synchronized
  • Date: Sat, 22 Mar 2008 00:42:32 -0600

Betsy,
 
Have you ever considered a Bordeaux mixture?  A mild Bordeaux mixture (2-6-100 or 3-3-100) can control blossom blight also.  Bordeaux can be in mixed in various formulas such as 10-10-100 or 8-8-100 plus superior oil.  The first number is the copper sulfate crystals.  The second number is hydrated lime.  The third number is water.  Superior spray oil can be used with the copper sulfate crystals only if the lime is also used.  The hydrated lime dilutes the phytotoxicity of the copper sulfate.  Under some weather conditions a mix may damage leaves or cause fruit to turn a russet color. I am including a mixture table for small quantities that should be suitable for most small scale uses.  The mixture must be agitated continuously. Do not apply mixes greater than 3-3-100 after 1/4-inch green leaf stage or when drying conditions are slow, as injury can occur.  Here's the recipe:
 
For 2-6-100 Bordeaux mixture: (for less severe blight or later in the growth stage of tree) 
 
4 tsp copper sulfate crystals
12 tsp hydrated lime
1 gal water
2 Tbsp spray oil
 
For 3-3-100 Bordeaux mixture: (for more severe blight or earlier in the growth stage of the tree)
 
6 tsp copper sulfate crystals
6 tsp hydrated lime
1 gal water
2 Tbsp spray oil
 
Dissolve copper sulfate crystals first. Mix in hydrated lime, constantly stirring. Finally, agitate the mixture as you add spray oil.
 
I hope this helps!
 
 
Dennis Norton
Royal Oak Farm Orchard
http://www.royaloakfarmorchard.com
http://www.theorchardkeeper.blogspot.com
http://www.revivalhymn.com
----- Original Message -----
From: <Hilborn.E@epamail.epa.gov>
To: "North American Fruit Explorers" <nafex@lists.ibiblio.org>
Sent: Friday, March 21, 2008 2:13 PM
Subject: [NAFEX] Copper spray timing when plants are not synchronized

> Hi all,
>
> I have planned my assault with copper spray on fireblight in my small
> orchard.  I have run into a small snag.
>
> My information is to spray elemental copper at green tip stage, and that
> it is important to spray the entire orchard for comprehensive
> protection.  I understand that copper can be phytotoxic if I wait too
> long.
> However, my collection of apples and pears are all at different stages
> of growth.  I have a pear tree in full bloom, another with emerging
> flower buds, some apples at green tip and some pears and apples still
> firmly dormant.
>
> I managed to spray the early pear by itself a couple of weeks ago as I
> realized the lack of synchronicity, however now it is getting
> complicated.
>
> Question: do I spray the green tip varieties AND the dormants or just
> the green tips and wait on the dormants?  I understand that the copper
> will harm the stages further along so I guess I need to skip trees.  I
> also understand that it wears off, so I expect I will need to spray the
> dormants as they become green tip.  Is it harmful to spray multiple
> times before bud opening, or should I just follow the green tip stage
> around the orchard and hope there is enough persistence of copper among
> trees?  It does not appear that I can saturate all the trees at each
> spraying as generally recommended as it seems I will harm new growth....
>
> Advice appreciated!
>
> Betsy Hilborn
> 7a NC
>
>
>
>



Archive powered by MHonArc 2.6.24.

Top of Page