Archives for April 2019

Allium leaf miner update: 09/20/19

Allium Leaf Miner

Allium leaf miner (ALM) feeding/egglaying scars were detected in chives and scallions near Princeton (Mercer Co.), NJ on Friday of this week.  This indicates that the second (fall) flight of these flies is now underway, and damage is occurring.

Allium leafminer oviposition scars on onion

Photo: Sabrina Tirpak. Allium leafminer oviposition scars on onion

Growers should consider initiating the control method of their choice at this time.  Affected crops include chives, scallions, garlic, onions and leeks.

Floating row covers, kept on until the second flight ends will help minimize access to plants.  Insecticide applications targeting adults may be helpful as well, although frequency of applications is uncertain.  Spinosyn materials (Radiant, Entrust (OMRI approved)), pyrethroids (Mustang Maxx, Warrior), and pyrethrin materials (Pyganic (OMRI approved)), neonicotinoids (Scorpion, Venom) and the insect growth regulator Trigard are labeled for miner control.

Adult activity and observations of feeding will be reported on in the IPM Update as they occur.  At this time, all growers should respond to the second adult generation.  We will attempt to identify the end of the second flight so that growers know when the risk of infestation has abated.

 

 

 

Improving Your Early Season Peach Brown Rot Control Program

Have you ever felt that you did everything right at controlling brown rot during the preharvest period, but still got a significant amount of brown rot at harvest? Your preharvest fungicide applications were at tight intervals during the roughly 21-day fruit ripening period. Rains occurred but you were protected. Even when you looked back at the bloom period you saw no obvious gaps in coverage. Yet, the brown rot appeared at harvest. If this is you, read on. [Read more…]

Tree Fruit IPM Report for April 15, 2019

Peach:

Brown Rot: Blossom infections from the brown rot fungus can occur whenever pistils are exposed and a favorable climate exists. Infections can occur during any wetting period when temperatures are between 41 and 86 °F. However, optimum conditions for infection occur with wetting and temperatures in the mid 70’s. [Read more…]

Optimizing preemergence weed control in established blueberry  for 2019

Several long-residual herbicides with different modes of action (MOA) are labeled for established blueberry. In order to reduce the potential of selecting for herbicide-resistant weeds, it is highly recommended mixing two residual herbicides with different MOA whenever you apply preemergence herbicides.

Casoron (dichlobenil) is a cellulose synthesis inhibitor recommended for fall application to control many annual and perennial broadleaves, grasses and yellow nutsedge.

The photosynthesis inhibitors (PS II inhibitors) have a broad spectrum of control and will be effective against many broadleaves and annual grasses when applied in spring. Karmex (diuron) and Princep (simazine) have relatively low solubility and have been very safe on blueberries. Sinbar (terbacil) has a longer residual life in the soil and also is more soluble, so it should be used infrequently on light, wet soils. Velpar (hexazinone) is very soluble and should not be used on very sandy or wet soils.

Kerb (pronamide) and Surflan (oryzalin) are mitosis inhibitor that will be effective at controlling many annual grass species for 4 to 6 weeks after application. Fall or spring application of Kerb can also be considered for perennial quackgrass suppression.

Solicam (norflurazon) is a pigment inhibitor that may be applied in fall or spring primarily for annual grass and sedges control. Solicam may also provide partial control of many broadleaf weeds as well as of yellow nutsedge.

Chateau (flumioxazin), Zeus XC (sulfentrazone), and Zeus Prime XC (sulfentrazone plus carfentrazone) are PPO inhibitors with activity against many broadleaves when applied preemergence in fall. They also have some postemergence activity on newly emerged seedlings of annual weeds.  Chateau has a 7 day preharvest interval (PHI) and Zeus/Zeus Prime have 3 day PHI, and can therefore be applied later in the season to extend preemergence broadleaves control into late summer.

Callisto (mesotrione) is an HPPD inhibitor recommended for spring application to control many annual broadleaf weeds as well as annual sedges. It controls large crabgrass but no other grasses, such as goosegrass. Callisto may be used as a broadcast spray between rows to control broadleaves and crabgrass without injuring the fescue sod.

Matrix (rimsulfuron) and Sandea (halosulfuron) are ALS inhibitors that have both preemergence and postemergence activity. They control most annual broadleaves but are weak on common groundsel, common lambsquarters and eastern black nightshade. Sandea is recommended for postemergence  control of yellow nutsedge. However, these two herbicides will not control ALS resistant weeds (horseweed, ragweed…) already widespread in New Jersey. Thus, these herbicides should always be tank mixed with a partner effective at controlling these weeds.

Devrinol (napropamide) and Dual Magnum (s-metolachlor) are long chain fatty acid inhibitor. Devrinol will provide good control of annual grasses and should therefore be tank mixed with a PSII or a PPO inhibitor for controlling broadleaf weeds. Dual Magnum has a shorter residual activity compared to other blueberry residual herbicides but will provides good yellow nutsedge, eastern black nightshade and pigweed control.

Make sure the herbicides you plan to apply will be effective at controlling the weed species in your field by checking the herbicide label. Usually, residual herbicides will suppress weed for 6 to 8 weeks depending on irrigation as well as soil and weather conditions. After this period, another residual herbicide can be needed to control weeds through harvest and could be mixed with a postemergence herbicides to control emerged weeds. Roundup (glyphosate), Rely 280 (glufosinate,) and Gramoxone (paraquat) are postemergence herbicides that may be applied with preemergence herbicides before bud break with little risk for crop injury.

 

Roughstalk bluegrass

Roughstalk bluegrass (Poa trivialis) is a cool-season perennial grass often considered a weed. Light green in color it is most obvious in the early spring when it grows more rapidly than other turfgrasses. As temperatures rise in the summer its growth will slow and it often goes semi-dormant until cooler temperatures and rainfall return in […]

Veg IPM Update: Allium leaf miner 04/10/19

Allium Leaf Miner

Allium leaf miner (ALM) feeding was detected in one commercial planting of chives near Lawrenceville, NJ on Tuesday of this week.  Degree-day accumulations at this site were 46.5, base 50 F as of Tuesday.  Sticky traps at this same site yielded no flies.  Additionally, trap and inspection sites at Milford (Hunterdon Co. (garlic)), and Oldwick (Hunterdon Co. (garlic and chives)), had neither feeding signs nor flies on sticky cards.

Allium leafminer oviposition scars on onion

Photo: Sabrina Tirpak. Allium leafminer oviposition scars on onion

Within the week, another monitoring site near Hackettstown (Warren Co.) will be added.    Reasonable spring weather that we are now experiencing is conducive to the development of the first adult generation.  Growers should consider initiating the control method of their choice at this time.  Affected crops include chives, scallions, garlic, onions and leeks.

Floating row covers, kept on until the first flight ends will help minimize access to plants.  Insecticide applications targeting adults may be helpful as well, although frequency of applications is uncertain.  Spinosyn materials (Radiant, Entrust (OMRI approved)), pyrethroids (Mustang Maxx, Warrior), and pyrethrin materials (Pyganic (OMRI approved)), neonicotinoids (Scorpion, Venom) and the insect growth regulator Trigard are labeled for miner control.

Adult activity and observations of feeding will be reported on in the IPM Update as they occur.  At this time, all growers should respond to the onset of the first adult generation.  We will attempt to identify the end of the first flight so that growers know when the risk of infestation has abated.