Fruit IPM Report for the Week Ending 4/20/2013

• Peach
• Apple
• Pear
• Scouting Calendar
• Blueberry
• Trap Counts
  

Peach

Oriental Fruit Moth (OFM): A biofix for OFM was set in southern counties on April 16. A biofix was just set in northern counties on April 22. The first of two full insecticide covers for OFM control should be applied between 170 and 200 dd after biofix. A second full insecticide cover should be applied between 350-375 DD.  Growers can monitor DD accumulations for their locality using the NEWA site (choose Oriental Fruit Moth in the drop down box under apple pests). Use the dates above for first trap capture. We will send out pest alerts as we approach these timings.

Green Peach Aphid (GPA): Aphid activity has been observed in only a few blocks currently. Growers can monitor by collecting a handful of blossoms and opening them to see if any aphids are inside. Beating trays may also be used. See last week’s report for more information.

Tarnished Plant Bugs and Stink Bugs (TPB and native Stink Bugs): Treatments also target these pests at this time. Growers who have experienced past problems have either had weedy ground covers and/or had plantings with considerable wooded borders. The cool spring we’ve been experiencing has not been conducive for catfacing activity.

Flower Thrips: Although early thrips injury is sometimes seen on both peaches and nectarines at harvest, they are generally considered more damaging to nectarines. Monitor for thrips the same as for aphids, collecting blossoms and examine the fruitlets. No thrips have been observed in southern counties as of this date.

Plum Curculio: This is one of the main insect targets at petal fall to shuck split. PC can also be active for several weeks following shuck split. The best materials include Imidan and Avaunt, followed by Actara and high rates of pyrethroids or premixes that contain pyrethroids. Anne Neilson at RAREC reports that PC is active in research blocks. At this stage adults are feeding and not ovipositing so only minor injury may occur. However, as peaches approach shuck split to shuck off considerable egg laying starts to occur.

Blossom Blight and Scab: The current weather pattern has not been favorable for blossom infections. Constriction cankers look very similar to blossom blight at this time, and have been observed in susceptible varieties. In the photo below note the sites of infection are different with constriction canker infecting a dormant bud, and blossom blight infecting an open blossom. Also note that the cankers are slightly different in appearance. The constriction canker does not yet appear sunken and has concentric rings while the blossom blight canker is sunken and is sporulating.

Peach Blossoms showing symptoms from: constriction canker (left); and brown rot blossom blight (right)

Maintain coverage with effective blossom blight fungicides at this time. Once shuck off begins growers can begin a sulfur based program. This does not apply to blocks known to have peach scab inoculum. In these blocks growers should continue a Captan based program until at least third cover. Other scab materials include Bravo, Gem, Topsin-M and Quadris Top. The active ingredient in Quadris is the same a.i. as in Abound. Therefore, don’t use this material near apples , or in the same sprayer used for apples, unless you are certain that apple cultivars you have are not sensitive to azoxystrobin.

Rusty Spot: If scab was was not an issue last year, Rally alone at petal fall is sufficient for brown rot and rusty spot. If scab was a problem last year Gem at the full rate or  Quadris Top (see above fr apple caution). will provide control of all brown rot, scab, and rusty spot at petal fall.

Bacterial Spot: Treatments using copper formulations or terramycin (oxytetracyclene) should be included in cover sprays starting at petal fall to shuck split. Terramycin formulations have limited residual activity, and are thought to have as much as 24 hours “back-action”. Terramycin works best when applied as dilute as possible and under slow drying conditions.  Reduce copper rates if spraying concentrate or if applying in hot weather. See the production guide for recommended materials and rates.

Apple

Apple Scab: Pink through 1^st cover generally coincides with peak ascospore release.  Using the development modeling at NEWA we are at approximately 80% ascospore maturity in southern counties as of this writing. Maintain coverage with very effective materials through this period. See last week’s report for more information.

Cedar Apple Rust: Rust is also a concern at this time of year. If using the strobilurin fungicides, Flint and Sovran, remember that they are not particularly effective for rust control. The best rust control materials continue to be the DMI materials such as Indar, Rally, Inspire Super, Procure. While the DMI’s are effective for both scab and rust, they must be combined with an effective scab protectant, usually an EBDC, for fruit protection and resistance management. In addition to the stand alone DMI’s for rust control, Inspire Super ( a premix of DMI plus AP), and Luna Sensation (a premix of QoI and SDHI) provide good rust control.  Inspire Super, and Luna Sensation are premixes that can cover the full disease spectrum at this time and can be applied alone.

Fire Blight: Blossom sprays using antibiotics should be applied anytime temperatures are 65° F or above and the relative humidity is 60% or above, especially if rain or severe weather is expected. Growers should rotate streptomycin with oxytetracyclene to manage resistance. Growers using Apogee for fireblight suppression should continue antibiotic programs, especially where late blossoms persist. Refer to the production guide for recommended materials and rates.

Plum Curculio (PC): PC adults usually move into orchards during bloom and begin oviposition sometime after petal fall. This is a key insect target from petal fall through mid June, with peak activity usually occurring from mid May through early June.

Pear

Pear Psylla: See the Production Guide for Psylla recommendations at petal fall. Recent work at Cornell indicates that Surround applied @ 50#/ac at the Dormant, White Bud, and Petal Fall stages effectively manages early season populations. This program is followed by a season long program of 1% oil applied at 150 GPA at no more than 2 week intervals effectively suppresses summer populations while also controlling pear rust mite and San Jose scale.  Note that oil should be applied at temperatures less than 80 deg F. to prevent russetting and phytotoxicity. Also note that oil may defoliate some Asian pear varieties. Neonicotinoids should be avoided any time significant bloom is present in the orchard. This is especially true if DMI fungicides are also to be used. Recent research has shown a strong synergism that increases bee toxicity when certain SI fungicides are tank mixed with certain neonicotinoid insecticides. The addition of 1 qt. of summer oil/100gal to the neonics will increase their efficacy.

Scouting Calendar

The following table is intended as an aid for orchard scouting. It should not be used to time pesticide applications. Median dates for pest events and crop phenology are displayed. These dates are compiled from observations made since 1995 in Gloucester County. Events in northern New Jersey should occur 7-10 days later.

Blueberry

Cranberry Weevil (CBW): Over the past 7 days 36% of beating tray samples have been positive for CBW. About 8% of the total samples have been at or above the threshold of 5 adults/bush.  This represents a decrease since last week. While most of the samples have been taken at wooded edges, one farm that was seen on 4/17 where the CBW level was near 0 at the perimeter, due to perimeter treatment with Asana, levels in the interior were above threshold.  In general this pest pressure is now too low for concern.  One of the most active weevil sites seen this season which was not treated is now almost at 0 levels due to flower bud development, and probably some help from cool temperatures.

Plum Curculio (PC): Te first PC adult was seen on a beating tray sample on 4/16 in Atlantic County. During the past 7 days, 5% of beating tray samples have been positive for PC.

Worms/Leps – Leafrollers and Spanworms: About 2% of beating tray samples have been positive for worms. Levels that are present are too low for concern at this time.

Tree Fruit Trap Counts – Southern Counties

Tree Fruit Trap Counts – Northern Counties