Frost

With the cooler temperatures this week and possible frost forecasted, it seemed like a good time to talk about frost.

Frost forms when an outside surface cools past the dew point.  The dew point is the point where the air gets so cold, the water vapor in the atmosphere turns into liquid. This liquid freezes.  If it gets cold enough, little bits of ice, or frost, form. The ice is arranged in the form of ice crystals.

Types of Frost
Radiation frost is frost in the form of tiny ice crystals that usually shows up on the ground or exposed objects outside. 

Advection frost is a collection of small ice spikes. Advection frost forms when a cold wind blows over the branches of trees, poles, and other surfaces.

Window frost forms when a glass window is exposed to cold air outside and moist air inside. Window frost is familiar to winter residents of cold climates. Indoor heat and cold outdoor temperatures cause this type of frost.

Rime is frost that forms quickly, usually in very cold, wet climates. Rime also forms in windy weather. Rime sometimes looks like solid ice.

Frost and Plants
Frost damage occurs when ice forms inside the plant tissue and injures the plant cells.  Frost damage may have a drastic effect upon the entire plant or affect only a small part of the plant tissue, which reduces yield, or merely product quality.

Direct frost damage occurs when ice crystals form inside the protoplasm of cells, whereas indirect damage can occur when ice forms inside the plants but outside of the cells.  It is believed that direct frost damage causes problems for protoplasmic structures.

Although the evidence is not strong, it seems that the rate of thawing after a freeze is also partially related to the amount of damage. Citrus growers in southern California commonly believe that slowing the warming process after a freeze night can reduce frost damage. In fact, growers justify operating wind machines longer into the morning following a freeze night in order to slow the thawing process.

Usually there are still a couple of good weeks of weather after the first frost.  While the first frost announces the coming of winter there are some things one can do to protect  plants:

• Harvest early
• Irrigate before the frost
• Cover your plants
• Irrigate during the frost
• Chemical sprays
• Heaters and wind machines

Protect your plants for the remainder of the growing season.  Soon winter will be here and we will be begin our winter garden tasks.

Additional Information

Understanding Frost - Cornell University

Frost protection: Physiology and Critical Temperatures - United Nations

Frost - National Geographic

IPM Notes from October 17th 2013

Notes: IPM for October 10th was rained out.  This will be the last official field day and crop report. It is likely that next Thursday will be harvest day for the popcorn, and harvest for the peanuts is still several weeks away.  Winter annuals are germinating and sprouting in the fields.  Deer are actively grazing the soybeans and peanuts.

Pheromone Traps

Trap #1 - Black Cutworm
1 possible lygus bug

Trap #2 - Corn Earworm
1 fly, 1 mystery moth (still unidentified), 1 noctuid, 1 Fall Armyworm moth, 1 beetle, 1 lygus bug.

Trap #4 - Fall Armyworm
10 Fall Armyworm  moths, 1 mayfly

Traps were retrieved for storage.

Field Corn Field
It has not yet been harvested. The word is that it was such a small field that they didn’t get a round tuit. (a round to it) The stalks are very dry and the ears are folding down. This is prime trouble if there were turkeys around. When the ears drop it is exactly at the right level to be picked clean. Yield should be around 170 bushels (our estimate was 177.25).

Popcorn Field
The tops of the ears have been heavily eaten by the birds. Where the tops have been eaten mold is forming. Moisture content is still too high to harvest without the need for further drying. Perhaps by next week we will be able to harvest.

Cover Crop Field

• Buckwheat is reseeding.  
• Soybeans are showing pod and stem blight.
• Sweet Corn Field
• The rye is up.

Hay Field
Winter wheat has been planted and is now coming up.

Soybean Field
Fully defoliated. Pod and stem blight is showing up, but will not affect crop yield due to maturity of crop and lateness of season. Moisture content still too high for harvest.

Wheat/Soybean Field
Foliage is turning and beginning to drop off. Stinkbug population is a concern due to their numbers, piercing of the pods, and the effect of keeping the soybeans green – delaying maturation of the plants.

Demonstration Plots

Tomatoes have been harvested and the plot cleared.

Peppers have been harvested and the plot cleared.

Groundhog radishes (Daikon) have germinated in the compost, quinoa, and cover plots.

Peanuts still exhibit potassium deficiency. Peanuts have grown in size, but the covering inside the shell is pink showing that they are not yet mature. We have noted that something is boring into the peanuts underground. We have not found the culprit.



A very special thank you to Roger Arnold for compiling this season's field notes and reports.

Weed of the Week - Oxeye Daisy

The oxeye daisy (Chrysanthemum leucanthemum) is short-lived perennial.  Originally brought here from Europe intentionally as an ornamental and incidentally as a contaminant of imported hay and grain seeds.

Natural History

Oxeye daisy plant with ray flower (A), disc flower

(B), seed (C), lower leaf detail (D), and rootstalk (E) - MSU

Leaves - Montana Weed Control Association

Flower - Oklahoma Biological Survey

The ox-eye daisy is a member of the Asteraceae family.  It is a perennial herbaceous plant with thin 1- 2' tall stems typically branch above to produce two or more flower heads; smells like sage. It is the only large white daisy that has escaped gardens.  The leaves are alternate, lobed and deeply cut.  The root system is densely fibrous and forms offsets from short rhizomes.

The ox-eye daisy looks like some asters and is often confused with the ornamental Shasta daisy. The Shasta daisy's flowerheads tend to be larger than the ox-eye and it is usually taller than the ox-eye daisy.

Management Strategies
Preventing spread and minimizing establishment is critical in the control of any weed.  For small patches hoe or hand-pull seedlings and young plants. This is most effective when done before oxeye daisy flowers and the seed is dispersed.  A wildflower seed mix may contain ox eye daisy, so read the label carefully before using any wildflower seed mix. Biological controls have not yet been developed to manage oxeye daisies.  Some other methods for control are:

• Hand pulling and grubbing (i.e. digging up the roots)
• Tilling
• Mowing
• Grazing
• Chemicals

See  Oxeye Daisy for details on management strategies.


Additional Information

Oxeye Daisy - Virginia Tech

Invasive Plants Ox-eye Daisy - Montana State University

Oxeye Daisy Identification and Control - Salt Lake County

IPM Notes from October 3, 2013

Pheromone Trap Results

Trap #1 Black Cutworm
No insects trapped, 1 spider

Trap #2 Corn Earworm
No insects trapped

Trap #4 Fall Armyworm
4 Fall Armyworm, 1 True Armyworm, no other insects

Field Corn Field
This field has not been harvested. We do not know why. However, we are observing that the stalks are becoming more brittle with many of the tops broken down because of the birds. We also noted that the ears have now broken downward so that the ears are pointing toward the ground. We believe that this field is very susceptible to storm damage and are unsure if it can be harvested.

Popcorn Field
The popcorn is being decimated by the birds. Many ears are eaten down halfway or more. It may be a race to see if the birds eat it all or if we get to harvest some.

Note: Our unidentified moths are now in the pollinator strip, the strip between the cover field and popcorn, and in the herb demonstration plot.

Hay Field
This field has been chemically ‘burned’ and the foliage there is dying. This is in preparation for rotating this field into wheat.

Sweet Corn Field
The field was drilled and the grain – we presume rye – is now coming up.

Wheat/Soybean Field
There are Harlequin bugs present. There are also a large number of stink bugs – predominately Brown Marmorated. However, we did discover another species and will take it to the office for positive identification – it may be a predator. (Lise emailed back that it is probably the nymph stage of the green stinkbug.) We are also finding several wooly caterpillars. Deer are still grazing the margins of the field heavily.

Pollinator Strip
There are still flowers blooming down low even though the weeds are upwards of 5 – 6 feet tall.

Demonstration Plots
 
Tomato
Ramapo production continues to outstrip SuperSonic production in the Fall.

Peanuts
Peanuts are showing greater potassium deficiency – possibly allowing some disease vectors to begin.

Compost plot
Has been cleared and planted with groundhog radish.

Quinoa plot
Has also been planted with groundhog radish.

Note: We found another interesting caterpillar this week. This one was on the Basil in the herb garden and was the same dark red color as the stalk of the plant.

Weeds identified this week:

• Henbit
• Wild Geranium
• Spiny Amaranth
• Amaranth
• Goose Grass
• Fall Panicum
• Shepherd’s Purse
• Pineapple Weed
• Lamb’s Quarter
• FoxTail
• VelvetLeaf
• MaresTail
• Pennsylvania Smartweed
• JimsonWeed
• Curly Dock
• Chicory
• Yellow NutSedge
• Bedstraw
• Dandelion
• Plantain – broad and narrow leaf
• OxEye Daisy

Thanks to Roger for compiling the notes for the week.

Pest of the Week - Lygus Bugs

Lygus bugs are small, oval-shaped insects that feed on a variety of crops and weeds. Several species infest canola and alfalfa. 

Natural History

Tarnished Plant Bug (Lygus lineolaris) - State of Maine

Washington State University

Young nymphs are tiny and light green in color. Older nymphs are larger, with noticeable black dots on their back, and well-developed wing pads. Young tarnished plant bug nymphs can easily be confused with aphids.

In alfalfa, a new generation can mature about the time the alfalfa is cut for forage. The new lygus bug generation leaves alfalfa seeking another crop.

The tarnished plant bug is among the most damaging of the true bugs and is known to transmit plant diseases. The bugs use their needle-like mouthparts to extract plant juices. Their feeding causes terminal growth to be yellowed or distorted thereby reducing plant growth and causing them to appear unthrifty. Leaves from damaged buds are sometimes ragged and discolored.  Adults and nymphs of Lygus lineolaris feed by sucking plant juices and a watery saliva is simultaneously injected into the feeding site to aid in the breakdown of plant tissues.


Management Strategies

Lygus bugs have several natural control agents. A tiny fairy wasp (Anaphes ovijentatus) in the family Mymaridae parasitises the eggs of the lygus bug.  Nabid plant bugs, big-eyed bugs, and spiders occasionally prey on young lygus bug nymphs. A European wash, Peristenus digoneutis, has been introduced into alfalfa fields in eastern North America where it parasitises about 40 percent of the tarnished plant bugs. One of the few parasitoids of lygus adults is a tachinid fly, Alophorella spp.

Additional Information

Plant Bugs (Miridae) - American Museum of Natural History

Insect Lygus Bugs - Washington State University 

Lygus Bugs - North Dakota State University 

Tarnished Plant Bug - Dept. of Agriculture, State of Maine 

Lygus Bugs - Manitoba Agriculture 

Family Mymaridae - UC Riverside 

Family Mymaridae - USDA 

Notes from IPM September 26th 2013

Pheromone Trap Results

Trap #1 - Black Cutworm
2 spiders, 3 larvae – 2 lygus bugs and 1 ladybug

Trap #2 - Corn Earworm
5 moths – 2 corn earworm and 3 noctuids, 1 ladybug, 1 crane fly, 1 katydid.

Trap #4 - Fall Armyworm
12 moths – all Fall Armyworm

Field Corn Field
This field will be harvested today. Bill brought a moisture meter – a Farmex MT3 Three grain moisture tester (corn, soybean, wheat, and can be adjusted for sorghum/milo). The field corn tested at 15.8% and 15.9%. It will be slightly lower later in the day.
Park service was harvesting some cornstalks for Smithville.

Popcorn Field
42.9% moisture content. Way too high for harvesting – probably another 3 weeks.

Today we noted a pineapple weed.

Note: there is still no identification on the moth captured last week. They are still very prevalent in the cover crop field near the popcorn.

Soybean Field
Soybeans are defoliated and drying. Moisture in the beans is still high – at a stage farmers call ‘gummy’. There is evidence of pod and stem blight, but the beans are unaffected. However, we did find some purple staining on a few beans from the cercospora.
Note: we found a very few plants that are still green and not defoliating. Agricultural scientists are exploring the possible connection of stink bugs and delayed maturity in soybeans.

Wheat/Soybean Field
Pods have filled nicely. This field will make and be harvestable.

In this field we found a caterpillar that was rolling itself into a leaf for cocooning. It is large, green, not hairy, and has a large brown head. Identification later.
Also wooly caterpillars, a harlequin bug, and brown marmorated stink bug – identified by white striping on antennae.

Demonstration Plots
 
Quinoa
Plot has been cleared and retired for the season. As far as we know, no quinoa sprouted or grew. Our climate did not provide conditions necessary for germination and growth.

Peanuts
Peanuts are still pegging. We learned that peanut farmers check the covering on the peanut for maturity (not the hull, but the cover around the seed). Covers are white now, but will turn through yellow to orange to red to brown. We want to harvest when the majority are between red and brown.

Tomatoes
Ramapo production outdid SuperSonic production for the first time since early in the summer.

Thanks to Roger Arnold for compiling this week's notes.

Notes from IPM September 19th 2013

Pheromone Trap Results

Trap #1 - Black Cutworm
2 black cutworm moths, 2 spiders, 1 unidentified larvae

Trap #2 - Corn Earworm
3 corn earworm moths, 1 fall armyworm moth, 5 noctuids, 1 lady bug

Trap #4 - Fall Army Worm
36 Fall Armyworm moths, 3 true armyworm moths, 1 small moth sent to office to identify (this is the same species moth as the one captured near the popcorn field.) 1 moth escaped.

Hay Field
5th and final cutting is down. Hay field will be ‘burned’; i.e. all plant cover killed with chemical spray, and then made ready for wheat.

Popcorn Field
The early variety is beginning to dry and is nearly ready. Plant stalks are dying. Birds are feeding on the tops of the ears. There is a lot of corn earworm present. The later variety is still maturing. In the strip between the popcorn and the Cover Crop Field there are a lot of small moths. We will capture one for identification to determine if they are after the popcorn.

Field Corn
Corn stalks are completely dead. Black line is evident on kernels. Moisture content is down to the mid-20% - near harvestable level. There is a small amount of mold present – but probably not enough to endanger its usability. Birds are feeding on the tops of the ears.

Note: Bird pressure on this farm is due to being near the migratory flyway.

Cover Crop Field
Buckwheat is seeding. Deer are feeding on the soybeans. Soybeans are beginning to pod. Soybean aphids have moved from the Wheat/Soybean field to these soybeans. Lady bug and lady bug larvae are present.

Wheat/Soybean Field
Ladybugs were able to control the aphid infestation. No spraying or other intervention was necessary. Pods are filling but it is still a race against the daylight to see if they will mature to a size that is marketable. Soybeans are also susceptible to frost. Deer are also feeding along the field boundary.

Soybean Field
Plants are dying and defoliating. Beans seem small – perhaps due to lack of a good hot summer. Beans will still need to dry down for 2 – 3 more weeks.

Demonstration Plots

Tomatoes
Possible Buckeye Rot in the tomatoes.

Peanuts
Blooming has stopped. There are lots of pegs and peanuts are formed underground. Now we will wait for the plants to die and the peanuts to mature.

Cover Plot
Buckwheat are reseeding and sprouting. Cowpeas are still blooming and there are now many pods. They are difficult to see unless you move the plants around.
We will be looking to identify sprouting daikon radishes.

Pest of the Week - Rough-leaved Goldenrod

Solidago patula commonly know as rough-leaved golden rod or swamp golden rod a member of the Asteraceae family is found throughout New Jersey.  It is native to most of the eastern United States, as far west as Texas.  Usually found in swamps, wet meadows, pond and bog borders and calcareous fens.  There are about 125 varieties of Goldenrod native to North America.

Photograph by Ramona Barrientos

Natural History

"There is an old legend that relates goldenrods to asters. Two young girls talked about what they would like to do when they grew up. One, who had golden hair, said she wanted to do something that would make people happy. The other, with blue eyes, said that she wanted to be with her golden-haired friend. The two girls met and told a wise old lady of their dreams. The old lady gave the girls some magic corn cake. After eating the cake, the girls disappeared. The next day, two new kinds of flowers appeared where the girls had walked: Asters and Goldenrods."

Photograph by Ramona Barrientos

And now for the rest of the story.  Rough-leaved goldenrod is a herbaceous perennial to 2 m. tall.  The stems are more or less strongly angled, glabrous below the inflorescence. The leaves strongly scabrous above.  The lower and upper leaves are dissimilar; the lowermost leaves are 4-10 cm wide, sharply toothed, with a somewhat sheathing petiole; while the upper leaves are gradually reduced but still toothed. The flowers are yellow. The heads in paniculiform inflorescences; inflorescence branches wide-spreading, recurved-secund; rays 5-12.

Additional Information

Goldenrods - Asters and Goldenrods of New England

Flora of North America

Vascular Plants of Wisconsin - University of Wisconsin

Inflorescence vs. Capitulescence

Pest of the Week - Harlequin Bug

The harlequin bug Murgantia histrionica (Hahn) is also know by other common names such as "Calico Back", "Calico Bug", "Fire Bug".  The harlequin bug injures the host plants by sucking the sap of the plants, causing the plants to wilt, brown and die. Like other stink bugs, they produce odors from their thoracic glands, using them as a defense against predators.  Plants commonly attacked by the harlequin bug include such crucifers as cabbage, cauliflower, collards, mustard, Brussels sprouts, turnip, kohlrabi and radish.

Harlequin bug - Colorado State University

Eggs of the harlequin bug, Murgantia histrionica (Hahn). Photograph by James Castner, University of Florida.

Natural History

Harlequin bug life cycle - UC Davis

Eggs of the harlequin bug resemble tiny white kegs standing on end in a double row. Approximately 12 are laid together, usually on the underside of the leaves of the host plant. Each egg is marked by two broad black "hoops" and a black spot. The eggs hatch in from four to 29 days, the time varying with the temperature.

There are five or six nymphal stages that feed and grow for four to nine weeks before they are capable of mating and laying eggs.  The head coloration of the nymphs ranges from pale orange, darker orange to black in the final nymphal form.

Adult bugs are 3/8-inch long and mottled red, black, and yellow or orange.

Management Strategies

Hand-picking and destruction of the insect pests and egg masses may deter damage where low numbers of insects are found. Hand destruction of the adults in the fall and spring as they emerge from "hibernation" before they lay eggs is an effective control. This may be aided by the use of trap crops of turnip, kale, or mustard in the very early spring or late in the fall after the main crop has been harvested. Once the pests have concentrated in these areas, they can be killed by applying insecticides or by covering the trap crop with straw and burning. Trap crops should never be used unless they can be given careful attention to destroy the bugs attracted to them.   Insecticides are generally not recommended in gardens for stink bugs.

Additional Information

Hemiptera - True Bugs - Colorado State University

True Bug Lifecycle - UC Davis

Harlequin bugs 2013 a growing problem in Pennsylvania? - Penn State University

Harlequin bug - Rutgers University

Notes from September 12, 2013

Weed of the Week: Bedstraw

Pheromone Trap Results

Note: trap collection data is for a two week period.
Trap #1 - Black Cutworm
2 Black Cutworm moths, 1 house fly, 4 spiders

Trap #2 - Corn Earworm
3 Corn Earworm moths, 1 click beetle, 20 noctuid moths

Trap #4 - Fall Army Worm
35 Fall Army Worm moths, 1 bumblebee, 1 spider

Wheat/Soybean Field
Kenny reports that the ladybugs have controlled the soybean aphids – great news.
We observed few active aphids, many ladybugs and ladybug larvae, and many aphid ‘mummies’; i.e. the empty shell of the aphid body.
Found 1 stink bug.

Cover crop Field
The buckwheat is blooming and looks very healthy. It is taller than the soybeans. It is tall enough that this field could be double cropped – that is to set the combine high enough to harvest the buckwheat and then lower it and harvest the soybeans. Interesting concept.

Field Corn
Kenny reports that moisture content is still in the mid 20’s.  Processors prefer moisture to be around 18% so there is still a need for more drying time.  Black tips are visible on kernels, which means the kernels have reached physiological maturity and are in stage R6.

Popcorn Field
Corn Earworm is present. Moisture content is still high. Hull formation is almost complete. Bill has obtained a kernel sheller so we are considering harvesting this crop and selling it.

Soybean Field
This field is beginning to turn. It is in the leaf drop stage. This soybean variety has a shorter photoperiod than our second planting in the wheat field.


Demonstration Plots

Peanuts are continuing to peg.

Cow Peas are still not showing many pods yet continue to flower.
In this plot we broadcast planted Tillage Radish or Daikon Radish/groundhog radish as another type of ground cover that has the additional advantage of holding soil nutrients in the radish tuber over the winter. Optimal planting would have been around August 15th.

Tomatoes – advantages and disadvantages of the different staking methods are becoming very clear. The smaller tomato stakes available to the home gardener are now beginning to break due to the heavy burden of the tomato foliage.
John reports that the Supersonic variety has out produced the Ramapo variety so far.

Peppers – our efforts with the peppers have paid off. Though production is reduced because of the kind of season we had, we are still harvesting peppers from all the varieties. There is a reduced amount of ‘heat’ in the hot peppers due to the amount of moisture and cooler days.

Hops – continue to produce cones near the top of the support system.

Quinoa – the jury is still out on whether we actually have a plant or not. The verdict is in however on whether quinoa is a viable crop for our climate – it is not.

Other notes:
We found a Harlequin Bug in the shed. It is reported that they are in the Community Gardens.  Visit our blog for more an upcoming article on this insect.



Thanks to Roger for compiling this weeks notes. 

Weed of the Week - Smooth Bedstraw

Smooth bedstraw (Galium mollugo ) is a serious weed in pastures, hayfields and field margins.  This plant typically occurs first along roadsides, progressively moving inwards. Its invasive nature allows smooth bedstraw to out - compete forage species, reducing the value of the stand.  Smooth bedstraw is especially problematic within lower input forage areas. This weed contains the toxin anthraquinone that can cause systemic toxicity and skin disorders in mammals. Poor animal performance on high diets of smooth bedstraw has been observed.


Natural History
There are at least 30 different bedstraws in North America, and many are perennials like smooth bedstraw.  Reproduction is by seed and by underground rhizomes.

• Stems - Stems are smooth, wiry, 4-angled, branched, and up to 3 feet long. Stems initially grow upright, but over time they become spreading and matted.

• Leaves - Leaves are 1/3 to 1 inch long, linear, bright green, and whorled (usually, there are 8 leaves per node on main stems and 6 or 7 leaves per node on branches).

• Flowers - Flowers are about 1/6 inch wide, white, and consist of tiny, 4-lobed petals. Flowers form in branched clusters at the ends of stems and branches throughout the plant.

• Fruits & Seeds - Seeds are kidney-shaped, hairless, and dark brown.

Smooth bedstraw ttem - Ontario Ministry of Agriculture and Food

Smooth bedstraw whorls

Smooth bedstraw showing flowers and whorls - Ohio State University

The genus name, 'Galium' is from the Greek word for milk and refers to an old use for the plant to curdle milk in making cheese.  The common name 'bedstraw' has two possible origins: the dried plant was used to stuff mattresses and it is said that bedstraw was placed in the manger at Bethlehem when Jesus was born.


Management Strategies
Manage hayfields by testing the soil and keeping nutrients and pH at levels where grasses and legumes will thrive. Apply nutrients and lime as needed.

Keep bedstraw plants from flowering, setting, and spreading seed, no matter which additional control option you use. In hayfields, try to get the haycrop mowed before bedstraw sets seeds. This will help control the spread, give the grasses a more competitive edge, and also provide you with a better-quality crop. Be aware of a second flowering and seed-production period.

Make sure to control the spread of seed. Mowers, balers, rakes, and tedders can carry substantial amounts of seed from infested fields to clean fields. Remove any source of seed from equipment when moving from field to field. Research is still inconclusive about the spread of bedstraw via manure applications.

Tillage and rotation is very effective in killing perennial crowns and new seedlings that may develop. Consider a weed-controlling cover crop such as buckwheat or sorghum-sudangrass hybrids as part of your reseeding regime. A new seeding will need optimum management to keep smooth bedstraw from reinvading the field.

Additional Information

Smooth Bedstraw -Virginia Tech Weed Guide

Commonly Found Weeds in Vermont Pastures - University of Vermont

Controlling Smooth Bedstraw in Hayfields and Pastures - University of Maine

Ohio Perennial and Biennial Weed Guide - Ohio State University

Pest of the Week - Armyworms

Cutworms and armyworms are the larvae (caterpillars) of several species of night-flying moths in the family Noctuidae.  The armyworm, Pseudaletia unipuncta, and fall armyworm, Spodoptera frugiperda, are generally considered minor pests, but they have the potential for explosive outbreaks in turfgrass.

Natural History

Armyworm Identification - University of Nebraska

Fall Armyworm
The fall armyworm is native to the tropical regions of the western hemisphere from the United States to Argentina. It normally overwinters successfully in the United States only in southern Florida and southern Texas. The fall armyworm is a strong flier, and disperses long distances annually during the summer months. It is recorded from virtually all states east of the Rocky Mountains. However, as a regular and serious pest, its range tends to be mostly the southeastern states.

Typical adult male fall armyworm, Spodoptera frugiperda (J.E. Smith). Photograph by John L. Capinera, University of Florida.

The moths have a wingspan of 32 to 40 mm. In the male moth, the forewing generally is shaded gray and brown, with triangular white spots at the tip and near the center of the wing. The forewings of females are less distinctly marked, ranging from a uniform grayish brown to a fine mottling of gray and brown. The hind wing is iridescent silver-white with a narrow dark border in both sexes. Adults are nocturnal, and are most active during warm, humid evenings. After a preoviposition period of three to four days, the female normally deposits most of her eggs during the first four to five days of life, but some oviposition occurs for up to three weeks. Duration of adult life is estimated to average about 10 days, with a range of about seven to 21 days


Armyworm
Armyworms get their name from their behavior of moving across fields in an army-like fashion. As larvae consume available food sources, they migrate as an army to new host plants. Though they feed primarily on grasses (oats, wheat, fall rye, corn, barley, and forage grasses), they can be a pest of some vegetables (bean, cabbage, carrot, onion, pea, pepper, radish and sweet potato).

The adult moth is uniformly pale brown to grayish brown in color, with a wingspread of about 1 1/2 inches. There is a characteristic small, white spot near the center of each front wing. The eggs are greenish white and spherical and are laid in masses. Mature larvae are about 1 1/2 inches long with a yellowish or grayish ground color, more or less tinged with pink. The dorsum is greenish brown to black with a narrow, broken, light median stripe. A dark stripe on each side includes the black spiracles in its lower edge. The subspiracular stripe is pale orange, mottled, and edged with white. 

Armyworm, Pseudaletia unipuncta or Mythimna unipuncta. (Marlin E. Rice)

Management Strategies

Naturally occurring predators such as ground beetles and rove beetles may be important in keeping armyworm populations low each year. Research conducted by Michigan State University has found over 12 species of parasitic wasps and several flies that commonly attack armyworm larvae.

There are several types of viruses, a microsporidium, and fungi that infect armyworm larvae. A cool and wet spring favors armyworm development while hindering parasite and predator populations.


Additional Information

Noctuidae - Butterflies and Moths of North America

Armyworm Identification - University of Nebraska

Fall Armyworm - University of Florida

The Arthropod Museum - New Mexico State University

Armyworm - University of Illinois - Urbana

True Armyworms - Scout Info Kentucky IPM Pest Information Pages

 Fall Armyworm - Rutgers University

Pest of the Week - Eastern Black Nightshade

Eastern Black Nightshade Seedling

Natural History

Eastern black nightshade (Solanum ptycanthum) is native to the Americas and is commonly found throughout the United States east of the Rocky Mountains. Nightshade begins germinating in May and can continue throughout the growing season. Although it can cause crop yield reductions, more importantly it can interfere with the harvest and lower crop quality.  Eastern black nightshade is a highly branched annual plant that grows 1 to 3 feet tall. Flowers have five reflexed petals and fruits are green berries that turn black at maturity. The plant can be found in cultivated fields, gardens, waste places and overgrazed pastures. Seeds germinate in the spring and early summer and plants flower from July to October with seed maturing in August through October.

Immature eastern black nightshade plants and berries are considered potentially toxic. Rapid ingestion of large quantities of highly toxic fruits of this plants can result in coma and rapid death. The concentration of toxic principle decreases in berries to safe or negligible levels as the plant matures. This alkaloid, solanidine, has been reported to cause nausea, vomiting, bloat, paralysis and even death if the plant is consumed before it has reached maturity. Even though livestock poisonings and deaths have been attributed to nightshade ingestion, species identification in such poisonings is not exact.

Managment Strategies

Mowing, plowing, disking, and cultivating are some of the more commonly used mechanical methods for field crop weed control. Existing nightshade infestations in hay crops or pastures can be controlled by timely mowing or swathing to prevent seed production. Repeated mowings may be necessary, however, due to the sporadic germination of the plant.



Additional Information

Management and Contorl of Nightshade - North Dakota University Extension Service

Eastern black nightshade - Weed Science University of Illinois

How Toxic is Eastern Black Nightshade? - University of Wisconsin Weed Science

Notes from August 29, 2013

Pheromone Trap Results

Trap #1 - Black Cutworm
1 stink bug, 1 leaf beetle, 1 fly (diptera)

Trap #2 - Corn Earworm
10 noctuid moths, 2 leaf beetles

Trap #4 - Fall Armyworm
1 Fall Armyworm moth, 1 True Armyworm moth

Weed of the week: Eastern Black Nightshade
Also looking at the seed head of Fall Panicum

Field Corn
Dent stage with some kernel tips showing black – very close to maturity
Still have approximately 3 weeks to dry to 15% - though if weather remains wet, farmer can choose to harvest at 18% and pay a drying fee rather than lose crop to late fall storms, sprouting, or mycotoxins in mold.

Popcorn Field
Ears appear to be fully fertilized. Hulls are starting to form on the kernels.
Mites are present.

Cover Crop
Buckwheat is blooming.

Wheat/Late Soybean Field
Explosion in the lady bug population in response to the soybean aphid. Scouting threshold is 250 aphids per plant. At this threshold the farmer has about 7 days to the spraying threshold of 1000 aphids per plant. Lady bugs can eat about 180 aphids per day, so we are watching to see if the lady bugs can keep the balance. With all the moisture in the ground, plants are not showing evidence of wilt associated with the aphids feeding.
Still in the reproductive phase with pods just beginning to set.

Sweet Corn Field
Has been mowed down. No decision on what to plant next.

Soybean Field
Nothing noted.

Hay Field
3rd cutting is in.

Demonstration Plots
 
Buckwheat is reseeding with emergence of new plants.

Peanuts are forming underground on end of pegs.

Clustered Mountain Mint is excellent for attracting every kind of pollinator.

Found many Soldier Beetle. These are similar to lightning bugs and feed on pollen or nectar so are found around flowering plants.


Note: next week will meet at RCE for Soil Test Interpretation Class. Potluck to follow.


A special thank you to Roger for compiling the notes for this week.

 

Notes from August 22, 2013

Some general observations:

• Mildew on cucumbers
• Parasitic wasp larvae on dead tomato hornworm
• Cercosporia on grapes
• Birds in the corn fields
• Ragweed shedding pollen

Pheromone Trap Results

Change pheromones in traps today

Trap #1 - Black Cutworm
1 black cutworm moth and 1 sap beetle

Trap #2 - Corn Earworm
2 noctuids, 4 sap beetles, 4 indeterminate insects

Trap #4 - Fall Army Worm
1 sap beetle

Bad year for bugs and a great year for plant diseases



Field Corn
Corn is in the dent stage with approximately one month to harvest. The corn plants are beginning to die back so kernels can dry. Because of the open ends on the ears we are seeing mold starting in the ears. If these lead to mycotoxins then the corn may not be useful for feed.

Corn smut

Popcorn Field
Both varieties are fully tasseled. We are seeing smut fungus in some of the tassels. There is some firing on the lower leaves showing nitrogen deficiency. We found a rootworm beetle that has come up to feed on the silks. Also found a brown marmorated stink bug.

We found some small caterpillars eating the leaves of an amaranth plant.

Wheat/Soybean Field
We are now seeing blooms – the plants have moved into the reproductive stage. There are no pods. We found Soybean Aphid – an aphid that is exclusive to soybeans. We also found ladybugs and lacewings. This infestation of aphids may be severe enough to warrant spraying.


Sweet Corn Field
The sweet corn has been harvested and evaluated. There are still ears available for gleaning. The plan is to disc under the corn and plant a cover crop. There is a lot of sap beetle present in the remaining ears.

Hay Field
Was cut today for Third cutting. Leaf hoppers are moving out – to any nearby crop.

Soybean Field
Growing along nicely. Evidence of Cercosporia and thrips.

Soybean Aphids

Demonstration Garden
 

Tomatoes – Supersonic yield is ahead of Ramapo yield. Potato beetles found (and crushed).

Tomato hornworm with wasp eggs

 
Peppers – show signs of bacterial spotting and thrip damage. Otherwise they have recovered well and are producing peppers.

Peanuts – are pegging

Peanut Pegs

Cow Peas – have very few pods so not likely to reseed itself. However it is an excellent cover crop allowing few weeds and filling in all spaces.
Buckwheat – our lesson learned is that buckwheat is density sensitive and would require better seed rate monitoring. However, surviving buckwheat is maturing and reseeding itself.

New plant – Path Rush. It looks like a clump of grass but is really in the rush family. It is sometimes called wire grass because of its tough stems. It has tiny flowers clustered at the stem tips. It grows in wet conditions but also likes compacted soils. In New Jersey it can be a wetland indicator species.

 Special thanks to Roger for the notes and Ramona for the photographs.

Dung beetles are saving the world!

A recent  article published in Entomology Today discusses a recent study by scientist in Europe which indicates that dung beetles living in cow manure may reduce the emission of methane.  To read more, click the link below:

Dung Beetles are saving the world from global warming

The Naming of Plants

Today I received an interesting blog update from the Cambridge Library Collection (CLC).  The CLC reissues scholarly books that are out of copyright and of lasting value.  A recent blog posting from the CLC discussed the naming of plants and I thought everyone would find it entertaining.  The link for the blog is given below.

Cambridge Library Collection - The Naming of Plants

Pest of the Week - Spiny Amaranth or Spiny Pigweed

Amaranth coming from the Latin amarantus is an imaginary flower that is said never to fade.  While spiny amaranth (Amaranthus spinosus) or spiny pigweed is one of the most common weeds found in fields and pastures and also seems never to fade.

Spiny amaranth (Amranthus spinosus)

Natural History

Spiny amaranth is an annual pigweed. A member of the Amaranthaceae family which includes other plants such as joyweed, pigweed and cock's comb.  The Amaranthaceae are mostly herbs and rarely shrubs or small trees comprising 65 genera and 900 species.

Spiny amaranth is an annual pigweed and can be as tall 5 feet.  Its stems and leaves are hairless and can have a reddish tinge.  The leaves are alternate and oval to egg shape. Spiny amaranth plants also have a pair of short spines at the base of leaf petioles.

Some pigweed plants(Amaranthus palmeri) are edible.  The use pigweeds as a crop is well documented.  The Aztecs cultivated amaranth as one of their crops.  They made a  dough out of milled amaranth and toasted corn seeds mixed with honey or maguey sap.  The dough was formed into idols for various religious festivals.  However, some pigweeds have been associated with nitrate accumulation is livestock and they considered toxic to cattle, goats and sheep.

Management Strategies

Mowing can suppress spiny amaranth growth.  However the plant will bounce back if mowing is not maintained. For smaller stands of weeds, manually remove plants before flowering occurs and seeds are produced.  Herbicides can be used on larger areas as a supplement to a cultural control program, but not as a replacement for a cultural control program.

Additional Information

Spiny Pigweed - Rutgers University

Pigweed - American Indian Health and Diet Project

Amaranthacaea - University of Hawaii

Hay Crop and Pasture Weed Management - University of Tennesse

IPM Notes from August 15, 2013

Pheromone Trap Results

Trap #1 - Black Cutworm
The trap had fallen to the ground due to wind. The trap contained 1 bumblebee, 1 ladybird beetle, and 1 black cutworm moth.

Trap #2 - Corn Earworm
1 click beetle, 5 noctuids, 1 crane fly, 1 unidentifiable beetle, and 3 corn earworm moths

Trap #3 - European Corn Borer – Inactive

Trap #4 - Fall Army Worm
4 sap beetles, 1 fall army worm moth


Helios Trap 
Inactive – display/demonstration only

Popcorn Field
Birds are sitting on the tassels and breaking them. We did not find evidence of borers though they are present in the sweet corn. Tassels are out on the early variety, but ears and silks are slow to develop. We noticed this in both the field corn and the sweet corn. Too much water is a different kind of stressor on the crop. We found corn smut on one of the tassels. It was noted that while this is a fungus it is also considered a food delicacy in some cultures. Popcorn harvest is being projected for late September or early October.

Note: Many of the cornstalks in all the corn fields are exhibiting purple stain and black stain on the stalks. These are bacterial diseases that are not currently threatening to the crop but are easily seen. Moisture from the frequent rains has been getting between the leaf and stalk, providing a nice moist environment for bacteria to grow. If that bacteria were to move to the ears and shucks, that would be a problem for sweet corn consumers who would reject it as visually unappealing. Popcorn, because of its harder hull is least affected. Field corn is affected only when the bacteria is actually producing mycotoxins in the ear which renders the crop inedible.

Corn Mutation

Grain Corn Field
Grain corn is in the dough/early dent stage. The milk ring is present and the kernels are still receiving nourishment from the plant (i.e. the kernel tips have not turned black).
A problem noted with this variety of field corn is that the ear has grown past the covering of the husk, exposing it to insects, birds, and moisture. Moisture/water in the ear can lead to two major problems; during late stages of drying the kernels may sprout, and it becomes a perfect environment for bacterial mold and fungus (remember, we did find smut) which will produce mycotoxins that make it unfit for feed.
We did find a Corn Earworm in the ear that we examined today.


Sweet Corn Field
Harvesting began on Wednesday. All of the varieties that were ready were harvested. The ears were then graded and those that were evaluated as consumer perfect (no insect damage, no environmental damage, no disease) were counted for yield. We will have to wait until the whole harvest is complete before we can get figures from Ray. However, we heard that 600 lbs of sweet corn were donated Wednesday. Picking resumes again on Friday and will continue intermittently as different varieties mature.

Wheat/Soybean Field
We are seeing leaf damage from defoliator insect species – about 10%. (Soybeans can tolerate up to 60% leaf loss before being adversely affected.) We found an ‘inchworm’ and leaf hoppers and suspect the presence of grasshoppers and beetles with chewing mouthparts. It is now August 15th and the soybeans are still in a vegetative stage with no evidence of blooms. This is becoming a concern as the soybeans are day-length sensitive. When the days become short enough, the plants will stop making flowers and pods and shift to maturing whatever is there.

Demonstration Plots

Tomatoes
It is now becoming clear that the trellis system makes it much easier to harvest. It is possible to use this system with as few as two tomato plants. It is difficult to find and then reach into the cages to harvest ripe tomatoes. Rotting and damage is occurring to the tomatoes that are in contact with the ground in the free-growing tomatoes. There may be a slight edge in production of the Ramapo variety.

Peanuts
Some pegs are into the ground. These should begin producing peanuts. Again, we are concerned that it is a race to the end of the growing season. An early frost would lessen our production of peanuts.

Cowpeas
Very small peapods are now present.

Buckwheats
Seeds are maturing and dropping off to reseed the plot. However, where the buckwheats were blown over in the windstorm almost none of them survived. Somehow, their stalks being in contact with the ground caused them to die.

Hops
Cones continue to mature and are ready for harvest. We are approaching the time when 75% of the cones would be ready which would be the time that a commercial grower would harvest the entire crop.

Peppers
We continue to harvest peppers. Our efforts in prevention and remediation have paid off – pulling back the mulch, feeding with Epsom salt.
 

Special thanks to Roger for compiling this week's report. 

IPM Notes from August 8, 2013

Welcome and a special thanks to the Fernbrook Farm students who were a great help all morning.

Pheromone Trap Results

Trap Report
Trap #1 - Black Cutworm
2 moths (Black Cutworm), 1 spider, 1 mosquito, 1 beetle (click)

Trap #2 - Corn Earworm
8 moths (noctuids) and 1 beetle (click)

Trap #3 - European corn borer
Borer – Inactive

Trap #4 - Fall Army Worm
1 moth – Fall Army Worm

Helios Trap
Inactive

Alfalfa Field
We used 2 sweepers to collect samples of the bugs present in the field. We found leaf hoppers (small but a large number), cucumber beetle, aphids, lace wings, forage loopers, and clover mites.

Hops
The hops are doing poorly with some having the tops dying. We are looking for borers but did not find any holes or other evidence. There are also leaf hoppers.

Sweet Corn
There is borer present in the corn tassels. Evidence includes the presence of frass and broken-over tassels. We found a borer but did not identify it specifically. It is causing the tassel stalk to weaken and fall over. There is also a purple color on the lower stalk that is a stalk disease. Bill says we would need to send it to the lab to get a specific identification. At this time these problems are not a threat to the crop. There is deer damage. They are eating corn silk and tassels.

Soybean Field
This is a late group 3 possibly a 3.8. This means mid to late October harvest.
They are still flowering. Beans are immature. The bean stalks close to the ground have become large and woody (possibly a result of all the rain and the branching of the plants) – this will be difficult for the harvester. We are still seeing Cercosporia and some Septoria. There is also evidence of thrips (leaf puckering).

Wheat/Soybean Field
We were specifically looking for nodule production as the plants show signs of nitrogen deficiency. The plants are just beginning nodule production so probably are nitrogen poor. It is also possible that they are lacking potassium. There are no flowers, so this field would be graded in the vegetative stage. It will probably harvest at the end of October.

Popcorn Field
Bill brought a Minolta Spad Meter to test for nitrogen.
“The chlorophyll meter is a portable, hand-held device that instantaneously measures the greenness (or chlorophyll content) of a plant in the field. Nitrogen (N) is closely associated with leaf chlorophyll; thus chlorophyll meter readings of corn leaves reveal the N status of the corn plants.”

A reader greater than 50 means that there is sufficient nitrogen. Our readings were between 50 and 60. The lower readings were in the areas of the field that have been stressed by flooding. 

There are two varieties of popcorn in the field – one short season and one long season. We are seeing the beginning of tasseling and the formation of ears on the short season variety. Cereal leaf beetle is present. We found a spot of ‘rust’.

Field Corn Field
Today we did the calculation of yield.
Take a full ear of corn. Count the number of kernels in a representative row. Count the number of rows. Multiply to get the average number of kernels per ear.
We did 8 ears as a representative sample and got an average of 638 kernels per ear.
(smallest ear 570,largest ear 720) 

Assume 1 ear per plant. Use the calculation of plants from May 23rd – which is 25,000 plants per acre. Multiply. The result is 15,953,125 kernels per acre.

Divide by 90,000 kernels per bushel. The result is 177.25 bushels per acre. This is the estimated yield for this field. Bill rates it as a ‘good’ yield. It should be profitable when all expenses are deducted.


Note: The identity of last week’s mystery weed is Fall Panicum.


Special thanks to Roger for compiling this weeks notes.