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Healthy Fruit 2011 Vol. 19:3

Apr 19, 2011

Current (through April 18) degree day (DD) Accumulations

Location: UMass Cold Spring Orchard (CSO), Belchertown, MA

Base 43: 123

Base 50: 22

Significant upcoming orchard events based on degree days (Base 43):

Pear psylla 1st oviposition: 40-126

Redbanded leafroller 1st catch: 108-174

Spotted tentiform leafminer 1st catch: 113-199

McIntosh green tip: 95-147

Current bud stages

Location McIntosh apple -- early half-inch green Gold Bosc pear --
swollen bud
Burgundy (Pearl) cherry -- swollen bud PF14 Jersey peach --
swollen bud
macapple pear cherry peach

The way I see it

I repeat—what a difference a year makes! Last year McIntosh was at full pink and cherries were in bloom on this date. We are getting to the point of -- dare I say it? -- late. That bodes well for frost issues (less chance of frost as season progresses), however, I always say it "all depends when the frost comes." (I know, cup is half-empty.) Getting apple scab sprays on has been a bit challenging with the wind, however, according to NEWA there have already been 2 apple scab infection periods @Belchertown since green tip.

If you are planting trees, keep these tips in mind:

  • don't plant when the soil is too wet, but plant as early as possible
  • soak tree roots in water for 24-48 hours before planting
  • make sure graft union is 4-6 inches above ground for hi-density (tall spindle) apple plantings; all others apples and dwarf cherries plant graft union 2 inches above ground level; peaches plant graft union at ground level

We hope to see you at one of the 2 twilight meetings this week.


2011 New England Tree Fruit Management Guide available

As a reminder, the 2011 New England Tree Fruit Management Guide is available for purchase.

The 2011 New England Tree Fruit Management Guide (NETFMG) is available NOW. For $50 you will receive the printed guide by postal mail.

Note that for 2011 the herbicide/weed control section has been completely revised, and all sections have been carefully reviewed for changes in 2011. Order yours today!

Also note that Commonwealth Quality produce certified growers should have the 2011 NETFMG in their possession to achieve the maximum score!

Scale control options

San Jose scale seems to have become more problematic in recent years. I have excerpted from a recent (April 18, 2011) Scaffolds Fruit Journal article by Peter Jentsch the control options for scale.

Pre-bloom (up to half-inch green) is the most effective timing for treating scale. Oil, Lorsban, Supracide 25-W, and Esteem 35WP are options at this timing.Thorough coverage with oil is essential, and the earlier timing (green tip) the better. The addition of the other chemicals with oil has dubious value. (I.e., oil alone is very effective at controlling scale as long as good coverage is achieved.)

Early post-bloom where Provado, Esteem, and Assail are commonly used to control scale. Control during this period will be more difficult to achieve than during the pre-bloom period. New scale products which warrant trying during this period include Movento 240SC and Centaour 0.7WDG.

Late post-bloom chemical treatment options are the same as above (early post-bloom), however, timing is critical using a degree-day model.


Pre-bloom nutrient sprays

The addition of urea (N), zinc, boron and magnesium to pre-bloom sprays has been shown to improve fruit set and quality of apple. Most progressive apple growers apply these sprays religiously before bloom. Here are some specific recommendations:

Urea (N) -- use 2-3 lbs. spray-grade urea per acre at pink and again at bloom.

Zinc (Zn) -- use 1 to 1-1/2 quart per acre most formulated zinc products (Sysstem Zinc, etc., see label for specific directions) at tight cluster to pink

Boron (B) -- apply 1 qt liquid boron (Solubor, Borosol, etc.) per acre at first bloom

Magnesium (Mg) -- not typically applied at this time, but Mg demand is high pre-bloom; apply liquid Mg formulation per label recommendation (for example Sysstem Mg at 1 qt. per acre)

For more information, see: UMass Fact Sheet F-126 Prebloom Nutrient Recommendations for Apples or Rutgers Plant & Pest Advisory


Useful links

UMass Extension Fruit Program

Scaffolds Fruit Journal

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