Rutgers Cooperative Extension
Peach:
Oriental Fruit Moth: Second generation timings are updated below. Second flight adults are still flying statewide. Treatments for the second generation have just finished in southern counties, and are going on now in northern counties. [Read more…]
Sweet Corn
The first European corn borer (ECB) flight is over, and no map will appear in this edition. Feeding percentages are now declining as affected plantings get treated and pass to the silk stage. No new feeding should occur until the second flight arrives.
Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample. As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels. It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time. This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.
Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen. Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn. Control with these materials is very inconsistent.
The highest nightly trap catches of ECB for the week ending 6/26/19 are as follows:
| Cedarville 1 |
| Denville 1 |
| Hillsborough 1 |
Corn earworm (CEW) moth catches in both trap types have decline dramatically over the past week (see blacklight map at left, and pheromone trap map below at right). We are entering the time of the season when CEW activity is at its’ lowest. Despite this, low numbers continue in southern NJ blacklights and in the much more sensitive pheromone traps. The overwhelming majority of activity is below Mercer County, with only scattered individuals in northern areas. Green areas on the pheromone trap map indicates a 4-5 day silk spray schedule. Blue areas represent a 5-6 day schedule, and white areas are 6-7 day. There
are far fewer CEW pheromone traps than blacklights, and the resulting map has much broader color bands as a result. It should also be noted that the pheromone traps are much more sensitive than blacklights. Therefore, the number of moths caught in pheromone traps required to generate a specific spray interval is much higher than the number caught in blacklight traps. It must be stressed that there is high variability in these catches, and growers should consult with their IPM practitioner on recommended spray schedules.
Based on our degree-day (DD) model for Sparganothis fruitworm, peak flight and first eggs hatched events are expected at around 884 and
Sparganothis degree-day model benchmarks
895 DD, respectively (see chart). As of June 20, Sparganothis has accumulated 1022 DD (using March 1 as biofix) or 883 DD (using April 15 as biofix; a biofix more realistic to New Jersey practices). Based on the April 15 biofix, we are at peak flight activity and eggs should start hatching within the next few days. Larval injury to fruit usually begins after the eggs hatch. If treatment is required (based on pheromone trap counts), sprays should be applied two weeks after peak moth flight (i.e., 1st week in July) and/or earlier (i.e., next week) if populations are unusually high. When bees are present, your option is to use an insect growth regulator such as Intrepid. Our “standard” recommendation has been, however, to wait until bees are removed to apply an insecticide. Your post-bloom options include Diazinon, Altacor, Delegate, Exirel, or Intrepid. Timing of insecticide application is critical; so, if needed, do not wait longer than July 5 to manage this pest.
Peach:
Oriental Fruit Moth: Second generation timings are updated below. Second flight adults started this past week in southern counties and are about to start this coming week in northern counties. According to the model, treatments for the second generation should be going on now in southern counties, and should start next week in northern counties. [Read more…]
Sweet Corn
European corn borer (ECB) moths catches have declined to very low levels over the past week and no map will appear in this edition. The first flight is complete. Feeding percentages have stabilized, and no new feeding should occur until the second flight arrives.
Growers should continue to scout whorl and pre-tassel stage plantings weekly and consider treating when infested plants exceed 12% in a 50 plant sample. As plantings proceed to the pre-tassel stage, ECB larvae may be found in emerging tassels. It is a good idea to treat individual plantings as they move into the full tassel/first silk stage one time. This eliminates any ECB larvae that have emerged with the tassels as they begin to move down the stalk to re-enter near developing ears.
Useful insecticides for this particular application include synthetic pyrethroids (IRAC Grp 3), spinosyns (including OMRI approved Entrust) IRAC Grp 5), and diamides such as Coragen (IRAC Grp 28) or materials such as Besiege which include the active ingredient in Coragen. Synthetic pyrethroids alone should NOT be used for corn earworm (CEW) protection on silking corn. Control with these materials is very inconsistent.
The highest nightly trap catches of ECB for the week ending 6/19/19 are as follows:
| Crosswicks 1 | Milltown 1 |
| Milford 1 | South Branch 1 |
Scattered corn earworm (CEW) moths continue to be captured in southern NJ blacklight traps through early this week (see blacklight map at left) although these catches have declined since last week. Early plantings, now silking, are at risk of infestation from this pest.
In the CEW pheromone trap network, catches have also declined
but remain highly variable, with higher numbers in the south, and very low activity in northern NJ (see pheromone map below at right). The green area on the pheromone trap map indicates a 4-5 day silk spray schedule. Blue areas represent a 5-6 day schedule, and white areas are 6-7 day. There are far fewer CEW pheromone traps than blacklights, and the resulting map has much broader color bands as a result. It should also be noted that the pheromone traps are much more sensitive than blacklights. Therefore, the number of moths caught in pheromone traps required to generate a specific spray interval is much higher than the number caught in blacklight traps. It must be stressed that there is high variability in these catches, and growers should consult with their IPM practitioner on recommended spray schedules.
This spring’s inclement New Jersey (NJ) weather has brought large amounts of precipitation in the form of rain, and concern about crop and forage losses. Rainfall, particularly during forage harvest season, can result in the production of low-quality hay and forages. This can result in lower forage intake by animals, decreased forage digestibility, and reduced animal performance. Table 1 describes crop progress this year. Rain has postponed some hay harvesting, however, according to USDA-NASS, NJ crop progress is similar to last year, but significantly less than a five-year average.
Table 1. Crop Progress as of June 16, 2019 (in percent)
| Item | This Week | Last Week | Last Year | 5 Year Avg. |
| Alfalfa Hay: First Cutting | 63 | 38 | 66 | 82 |
| Other Hay: First Cutting | 56 | 32 | 61 | 70 |
USDA-National Agricultural Statistics Service, NJ
It is important to remember that the amount of rain New Jersey has had this spring is no guarantee that there will not be a drought that lasts into the fall.
When summer temperatures rise as they often do in New Jersey, the first sign of heat stress may be declining feed intake followed by declining milk production, decreases in weight gain, and decreased overall performance. All livestock producers may observe decreased rates of gain and feed efficiency in growing animals, declining reproductive efficiency and performance, and possibly health and disease related problems.
Anyone who has entered a dairy barn on a cold winter day knows how much heat cows can produce. In the summer, though, this extra heat, which comes from digesting feed and producing milk, causes a cow’s heat load to increase. When a cow can’t get rid of excess heat, she will stop eating and milk production will decline. Table 2 lists the typical thermoneutral zones for several domestic livestock species. Below these temperature values (Lower Critical Temperature), an animal will have to expend extra energy to maintain body temperature.
Providing extra feed or shelter or other protection from the elements are good ways to help animals stay warm. Above these temperatures (Upper Critical Temperature) animals will have to get rid of extra heat. An animal’s first response when atmospheric temperatures are elevated may be to stop eating. This will lower the heat load, but growth, reproduction, and milk production will all be affected. Please remember that the values in Table 2 are not adjusted for the effects of humidity, wind or wind chill, or inclement weather. These will also vary by species, breed (beef vs. dairy), length of hair coat, shorn vs. unshorn, etc.
Table 2. Typical Thermoneutral Zones (Upper and Lower Critical Temperatures in Fahrenheit)
| Species | Temperature o F |
| Cattle | 32-61 |
| Calves | 54-75 |
| Sow | 32-59 |
| Hen | 64-82 |
| Sheep | 27-67 |
NRC. 1981. Effect of environment on nutrient requirements of domestic animals. National Research Council. Washington, D.C.: National Academy Press.
Since animal production is a farmer’s livelihood, what are some strategies to keep animals cool? First, it is important to remember that most domestic livestock animals, excluding horses, have few sweat glands. This means that they will not lose heat by evaporative heat losses through sweating. The first strategy should be to provide abundant supplies of cool water for drinking. Water will help to cool animals and help maintain feed intake. This is especially important in the case of lactating dairy cows that may need 30-40 gallons of water a day to maintain milk production. Second, shade from shelters or trees in pastures will reduce the effects of radiant heat from the direct rays of the sun. Keeping animals sheltered in the day and turning them out on pasture at night will limit the effects of radiant heat and allow animals to cool. Third, water sprinklers or misters will help cool animals and relieve some of the effects of heat. Animals, particularly cows or pigs, will seek out water if available for cooling. It is common in certain parts of the country for cows to stand in ponds or streams. This is not recommended because of concerns about contamination of water supplies, and in the case of lactating cows there are concerns about mastitis disease infections. In modern confinement systems, pigs are often housed in climate-controlled barns. Pigs will wallow in mud if given the opportunity; this can be a good means for cooling if no other options are available and provided environmental concerns are adjusted for. In addition to protecting from the heat of the sun, shade will also protect pigs from direct rays of the sun that can cause sunburn for a light skinned pig. Fourth, fans are also useful for cooling; air currents over an animal’s body will disperse excess body heat. Fans, when used along with shade, and sprinklers or misters, will promote evaporative cooling, an excellent means of reducing an animal’s heat load.
There are some feeding strategies that may help to manage heat stress. First, consider increasing the energy density of the diet. This can be accomplished by decreasing forage and fiber levels (consult a nutritionist before dietary forage or fiber levels are reduced for ruminant animals) or by adding an energy source such as extra grain, or fat, or perhaps oilseed products in the diet. Since much of an animal’s heat production comes from digestive heat, increasing energy density will increase energy relative to digestive heat production; this is particularly true when feeding ruminants. For dairy cows fine-tuning the diet through the addition of bypass proteins, yeast or minerals may also be helpful. Before making any dietary changes in response to concerns about heat stress, consult with your feed company’s nutritionist.
There are effective means of dealing with heat stress during the summer. Provision of abundant supplies of cool water, the use of shades, fans, sprinklers or misters, and properly managed diet modifications can all be effective approaches for dealing with summer heat stress.
This article was written by Michael L. Westendorf, Ph.D. Rutgers University School of Environmental and Biological Sciences Department of Animal Science. It appeared previously in the June 15 issue of the New Jersey Farmer.
