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Purple Power

Pest: Beetle Borers ~

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Pest: Beetle Borers

 

 

(Multiple Species)

 

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The European Corn Borer

 

 

Warning:

 

The European Corn Borer (ECB) and Hemp Borer (HB) are the two most destructive caterpillars. I will constraint on them, but will give a brief description on the others in the common species section. To tell the difference of which one is attacking depends where the plant is attacked.

 

 

There are few caterpillars cause as much damage as ECBs and HBs.   An exception is the budworm (e.g., Heliothis armigera, Heliothis viriplaca, and Pieris rapae).  Budworms wreck havoc on flowering buds, but leave stems alone.

Here's the link for the budworm species Pieris rapae:   http://freemygreenpdx.com/topic/14470-pest-cabbage-butterfly/

 

These pests will feed on the centermost part of the cannabis plants’ stalk, the marrow inside the stalk causing stem cankers to form. Starting with the creation of holes within the stem, which also allows an opening for other pests ( bug, mildew, etc.) easy access. This feeding ruptures the plant's support system and eventually causing heavy flowering bud sites to topple over and entire plants to collapse.

 

The hemp borers are almost exclusive host-specific to the Cannabaceae  family. They are known to attack hemp, cannabis, hops, and sometimes knotweed. They are more destructive and can consume an average of 16 cannabis seeds per larva. Because they are so host-specific to cannabis family, anti-cannabis researchers have been flagged as the HB as a potential bio-control agents (using other living organisms to control pests by relying on predation, parasitism, and herbivory) against our cannabis.

 

The best thing to do, especially when problems with stem boring caterpillars occurred in the past, is to be one step ahead, preventing the eggs of butterflies to hatch, and the larvae to consider your plants as a potential nourishment.

 

 

 

 

Special Species Notes

 

The European corn worm or European corn borer (Ostrinia nubilalis), also known as the European high-flyer, is a pest of grain, particularly maize. Wild hop (Humulus hupulus) and wild hemp (Cannabis sativa) were the original host plants of ECB. During the last 200-300 years,  maize, sorghum, cultivated hemp, cultivated hops, and corn became the main host plants of ECB. The insect is native to Europe, and found in northern Africa.

 

The North American European corn borer population is thought to have resulted from multiple introductions from more than one area of Europe. Thus, there are at least two, and possibly more, species present.  The European corn borer was first reported in North America in 1917 in Massachusetts, but was probably introduced from Europe several years earlier.  Since its initial discovery in the Americas, the insect has spread into Canada and westward across the US to the Rocky Mountains, and south to the Gulf Coast states. They occurs infrequently in Florida. They are is a common pest of corn in North America, particularly east of the Rockies.

 

Corn borers on the stem are devastating. The reason for this is that they create an opening for other pests that destroy the host plants by sucking the all-so important sap. The sap plays a critical role in the flourishing of the crop, so when it is eliminated from the plant it causes death. 

 

Hosts of the common stalk borer include such crops as corn, fruits, other vegetables, and flowers. The larvae feed on leaves or burrow into the stem of the plant making the plant appear wilted or deformed with visible holes on the leaves and stems.

 

Hemp borer are smaller the ECB. Hemp borers also called hemp leaf rollers and hemp seed eaters.  Besides boring into stems, they destroy flowering tops/buds, and devour seeds.  Each larvae can consume sixteen cannabis seeds.  They can destroy 80% of flowering tops, hemp seeds were 30-40%, and losses of stalks were damaged sometimes by 100%.

 

Both types of caterpillars have a destructive effect on your cannabis crop, and for this reason, you need to get rid of them immediately.

 

 

 

Identification

 

For the ECB:

 

Adult: Wingspan of 3/4 to 1¼ inch; female moth are larger than the male moth. Several dark zigzag markings across the wings. The adult moths typically fly at night and are not attracted to light. The adult female is capable of laying up to 2000 eggs per season. Total adult longevity is normally 18 to 24 days. Moths are most active during the first three to five hours of darkness. Dispersal of moths and disruption of moth emergence by heavy rainfall are thought to account for high and variable mortality (68 to 98%, with a mean of 95%), which largely determines population size of the subsequent generation. Overall generation mortality levels were high, averaging 98.7%.

 

 

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Female ECB

 

Female moths: thicker body, yellowish buff to light tan wings. both the forewing and hind wing crossed by dark zigzag lines and bearing pale, often yellowish, patches. Wingspan for females 25 to 34 mm.

 

 

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Male ECB

 

Male moths: thinner body, The male is darker in color darker; tan-to-grayish brown wings also with dark zigzag lines and yellowish patches. Males measuring 20 to 26 mm in wingspan.

 

Life History: 1st generation larvae over-winter in stalks of host plant, transform into pupae in late April to early June. Adults emerge and lay eggs mid-May to mid-June. Larvae chew holes in leaves, then into stalk, where they pupate. 2nd generation moths emerge in late July to late August.  Larvae complete growth before cold weather and overwinter in plants. The number of generations varies from one to four, with only one generation occurring in northern New England and Minnesota and in northern areas of Canada, whereas three to four generations occur in Virginia and other southern locations. In southern locations with three generations, moth flights and oviposition typically occur in May, late June, and August. In locations with four generations, adults are active in April, June, July, and August-September.  In many areas generation number varies depending on weather, and there is considerable adaptation for local climate conditions.

 

Eggs: whitish eggs are glued to underside of leaves laid individually or in groups during late summer or early fall in grasses or rolled up plant leaves. They resemble over-lapping fish scales. Eggs will then overwinter and hatch in late April or early May. It can take a period of four to five weeks for all eggs to hatch. Eggs hatch in five to six days (72 degrees to 77 degrees F.), or three to four days (78 degrees to 82 degrees F. Egg mortality (about 15%) was low, stable and due mostly to predators and parasites.

 

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Eggs of ECB

 

Larvae: Young larvae are initially dirty white; color may change to light tan or pinkish gray as larvae mature. 1/3-5/8” in length. Skin is smooth and free of hairs with numerous round dark spots scattered over top and sides with dark head. Four prolegs (3rd, 4th, 5th, 6th and 10th abdominal segments). They are ¾ to 2 inch long ECB larvae are relatively easy to identify because of their distinct coloration. Mortality of young larvae, due principally to dispersal, dislodgement, and plant resistance to feeding was fairly low (about 15%) but more variable.

 

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As the larvae mature however, the distinguishing white lines disappear, and the majority of body color turns to a light brown to brownish-gray or pinkish gray in dorsally, with a brown to black head capsule and a yellowish brown thoracic plate. The body is marked with round dark spots on each body segment. The developmental threshold for larvae is about 51F (11°C). Larvae in the final instar overwinter within a tunnel in the stalk of corn, or in the stem of another suitable host. At this later stage they can be confused with both the cutworm. Mortality of large larvae during the autumn (about 22%) and following spring (about 42%) was due to a number of factors including frost, disease and parasitoids, but parasitism levels were low.

 

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Pupae: Pupae usually occur in April or May, and then later in the year if more than one generation occurs. The pupa is normally yellowish brown in color. Remains inside host plant; smooth, yellowish- brown to dark brown in color. The pupa measures 13 to 14 mm in length and 2 to 2.5 mm in width in males and 16 to 17 mm in length and 3.5 to 4 mm in width in females. The tip of the abdomen bears five to eight recurved spines that are used to anchor the pupa to its cocoon. The pupa is ordinarily, but not always, enveloped in a thin cocoon formed within the larval tunnel. Duration of the pupal stage under field conditions is usually about 12 days. The developmental threshold for pupae is about 55F (13°C). Pupal mortality (about 10%) was low and stable among generations.

 

 

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For the HB:

 

Hemp borers arrived in North America around 1943.  Species are differentiated by their genitalia. The hemp borer, are true experts of camouflage, and eggs are hard to spot.

 

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Adult HB

 

Adults are dark brown with two pair of white dorsal strigulae on each forewing. Hindwings are dark brown. Forewings strongly varying in color from light brownish-ocherous to dark brownish-red. Outer margin of forewing bearing 9 oblique light yellow stripes directed backward. Four slanting light yellow stripes located in the middle of inner margin. Fringe of forewing is dark gray with metallic shine. Hindwings grayish-brown. The adults life less than two weeks.

 

Wing pattern is similar to other Grapholita, especially Grapholita tristrigana in eastern North America. The dorsal strigulae in G. delineana are usually narrow and distinctly separated, while those in G. tristrigana may be confluent. The two species can be separated by genitalia: in G. tristrigana the male aedeagus tapers evenly and females lack a signum in the corpus bursae.

 

Male: Wingspan 11.5 mm. Male genitalia are characterized by an aedeagus that narrows abruptly.

 

Female: Wingspan 15 mm.  Female genitalia are characterized by two signa in the corpus bursae.

 

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Adult HB

 

 

Eggs: Eggs are transparent to white to pale yellow and oval (0.6 mm in length, 0.4 mm. wide) laid singly on stems and leaf undersides. They have thin and wrinkled shell. Females of spring generation lay eggs one by one or by 2-3 on the lower side of hemp leaves (to 60% of eggs), on their upper surface (to 30%), on stalks and petioles (about 10%). Moths of the subsequent generations lay eggs in abundance on inflorescences. Fertility of females of the wintered generation is 100-200 eggs on average, and 350-500 eggs in the subsequent generations. Caterpillars hatch in 8-10 days at temperature 20-22° C.

 

Larvae are similar to those of other Grapholita. An anal comb is absent. Caterpillar light yellow to bright red, 8-12 mm in length, with light yellow-red head. Prothoracic shield light yellow and transparent. Abdominal legs with 16-20 hooks forming a uniserial crown.

 

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Pupa light brown, 5-7 mm in length, with 2 rows of spinules directed backward on dorsal side of 2nd-8th segments. Caterpillars of the last (usually 5th) instar winter in the cocoons covered with soil particles and located at roots, in a surface soil layer to a depth of 5-10 cm, within plant residues in fields, in places of thrashing, retting, storing, and also in thickets of wild growing hemp. Larvae pupate in silken loose cocoons covered with bits of hemp leaf. 

 

 

 

Common Species:

 

 

 

European corn borers (ECBs) , Ostrinia nubilalis, attract a lot of scientific attention thanks to their amazing appetite for corn plants.  ECBs are native to eastern Europe, where Cannabis sativa and Humulus lupulus (hops) served as original host plants.  ECBs switched to maize after corn/maize ,Zea mays, cultivation began in Europe two centuries ago. About one century ago, ECBs moved to North America and plagued American hemp, where they nourished themselves upon the marrow within stalks. It's been recorded that it has at least 230 different host plants.

 

ECB feeding induces stem cankers, which are structurally weak.  Stems supporting heavily flowering tops often break at cankers.   Larvae boring into smaller branches cause wilting of distal plant parts.   Under heavy infestations entire plants collapse. 5-12 larvae can destroy a hemp plant.  ECB entry holes in stems are essentially open wounds, providing access for fungi such as Macrophomina phaseolina. Other insects may also crawl in.  ECBs hatching late in the season may infest flowering tops instead of stems, where they spin webs and scatter feces

 

Hemp borer (Grapholita delineana), are smaller than ECBs. HBs cause similar stem damage, but are much more destructive in flowering tops.  HBs are also called hemp leaf rollers and hemp seed eaters.  In Russia, HBs have destroyed 80% of a crop's flowering tops. It's been reported 41% seed losses.  Each larva consumes an average of 16 Cannabis seeds. HBs appear host-specific on Cannabis. 40 larvae will kill a Cannabis seedling (15-25 cm tall) in 10 days.  As little as 10 larvae per plant cripple growth and seed production. There are 126 species that are currently recognized in genus Grapholita

 

Other Cannabis caterpillars feed as stem borers:

 

Goat Moth, Cossus cossus: It is found in Europe. This is a large heavy moth with a wingspan of 68–96 mm. The wings are greyish brown and marked with fine dark cross lines. The moth flies from April to August depending on the location. The caterpillars feeds on wood in the trunks and branches of a wide variety of trees, taking three or five years to mature.

 

Zeuzera multistrigata: found in India, Nepal, Myanmar, Bangladesh, Sri Lanka, Vietnam, China, Dorea, Russia, Japan, Taiwan, and Australia. Was introduced to the southern IS and west Africa. Wingspan is 35 mm for males and 70mm for females. The egg lasted 8-9 days. Eggs laid singly or in masses of 3-8 in cracks or crevices in stems, near buds or in the soil round trees in June-July. The larva stage 20-22 months. Larval feeding in the early instars on th cambium caused gummosis, while the later instar penetrate into the hardwood making tunnels 20-25cm long from March-April until the following year. the foliage of infested trees tur yellow or brown and drop off. Pupae last 4-8 weeks. pupae present in April-May and adults in June-July. adult stage 10-23 days.

 

Larva feed on Australian pine, ironwood, whistling pine, Filao tree, beach casuarina beach oak, beach she oak, whistling tree, horsetail she oak, horsetail beefwood, horsetail tree, coast she oak agoho, and cherry trees.

 

Stalk borer, Papaipema nebri, Native to North America; found from southern Canada through the Western US to the Gulf of Mexico.  Wingspan is 25-44 mm the moth flies from June to September. the larva are peat of corn and other large-stemmed plants. The insect belongs to the Noctuidae family of moths, which includes the cutworms and armyworms. It's been recognized as a problem in Pennsylvania agriculture for approximately 150 years. In 1840 it was recorded as causing considerable damage to wheat in Chester and Delaware Counties. Other reports described its injury to corn, potatoes, and garden plants. In 1927 it was listed among the ten most destructive insects in the United States.

 

The young larvae are cylindrical and fairly slender, with markings distinguishing them from similar borers. The body is light brown with a narrow white stripe running from head to tail down the back. A similar white stripe on each side of the body is interrupted by a purplish-brown band that circles the front third of the body. When disturbed, the larvae are very active, moving in a looping manner to escape.

 

The moths are reddish-brown and resemble cutworm moths. The eggs resemble those of other members of this family, being globular, sculpted, and pinkish-brown.

 

Stalk borer larvae are known to feed on more than 200 species of wild and cultivated plants, ranging from grasses to trees. Small grains, corn, forages, and vegetables are all subject to their attack.

 

Burdock Borer,  P. cataphracta, found from Quebec and Maine to Florida, west or Louisiana and north to Saskatachewan. the wingspan is 29-45mm. the moth flies from August to October. The larva feed on various plants like Arctium, Lilium and Thistles. They bore into the roots and stems of their host plants.

 

Hemp Ghost Moth, Hepialus humuli, also known as the ghost swift. Wingspan of about 44mm both forewings and hindwings are pure white. female win gspan about 48 mm. and has yellowish-buff forewings with darker linear markings and brown hindwings. The adults fly from June to August and are attracted to light. The ghost moth gets its name from the display flight of the male, which hovers, sometimes slowly rising and falling, over open ground to attract females. They bore into the stems.

 

endocylyta excrescens: It's from Japan and Russian far east. It makes galls. Known host plants are  Tobacco, cannabis, hemp, Chestnut, Paulownia, Oak, Radish.

 

Squash Vine Borer (Melittia cucurbitae) Primary Host: Squash, zucchini, pumpkins and gourds. Butternut squash is less susceptible to damage.

 

Damage: Larvae bore into the vine, causing a sudden wilting of a vine or an entire plant.

 

Life History: Overwinter as pupae inside tough silk-lined cocoons in the soil. Adult moths emerge in late June. Moths fly during the warm part of the day and lay egg s on the stems near the soil surface. Eggs hatch in about 10 day s and the tiny borers enter the stems, hollowing out the stems. Toward the end of the season when vines become woody and less succulent, the borers may attack the fruit. Borers leave the plant in August and September, when mature and enter the soil to form their overwintering cocoons.

 

Insect Description:

 

Adults: A clear-winged moth that looks like a wasp with metallic live-brown wings and a red-orange

body. Wing spread is 1¼”.

 

Pupae: Cocoons are formed in the soil for overwintering.

 

Larvae: 1” long white grub-like caterpillar that enters the vine and feeds, pushing out masses of greenish-brown sawdust-like frass.

 

Eggs: Reddish-brown eggs are laid on the vines when the vines begin to run.

 

 

Other insects may also bore into stems as grubs or maggots:

 

Flea beetles (Phyllotreta nemorum): the grub. Flea beetles transmit viral and bacterial diseases.  There are one to four generations per year, depending on species and climate.

 

Many species of flea beetles are found throughout the United States. They are small jumping insects (similar in appearance to fleas) commonly found in home gardens early in the growing season.  Adult flea beetles feed externally on plants, eating the surface of the leaves, stems and petals. They damage plants by chewing numerous small holes in the leaves, which make them look as if they have been peppered by fine buckshot. Some of the larva are root feeders.   When populations are high, flea beetles can quickly defoliate and kill entire plants. They feed most on hot sunny days and attack a wide variety of plants including beans, cabbage, corn, eggplant, cannabis, potatoes, peppers, tomatoes, lettuce and most seedlings.

 

Adults overwinter in the soil or garden debris and become active in the spring, feeding on host plants as new growth appears. Adults are small (1/10 inch long), shiny, dark brown or black beetles with large hind legs that allow them to jump when disturbed. Some species may have white or yellow stripes on their wing cases. Tiny white eggs are laid on or in soil cracks around the base of plants. These hatch in about one week. Larvae are small, cream-colored worms (1/8 – 1/3 inch long). They live underground and feed on the roots and tubers of young plants as well as on germinating seeds.  They feed on plant roots for approximately 2-3 weeks.  Pupae usually remain in the soil for 7-9 days until adults emerge and the cycle is completed

 

Tumbling flower beetles (Mordellistena micans and M. parvula): Also known as the pintail beetle.  They are worldwide, there are about 1500 species. These are very active beetles and strong fliers, but typically fall from plants to the ground when approached. They use enlarged femurs on their hind legs to kick off from the substrate and tumble, hence their common name. They move by a very rapid separate jumps.

 

These black beetles are small and covered with fine hairs and are humpbacked and wedge-shaped. They have elongate, beetles 3.0-5.0 mm (1/8 – 3/8 inches) in length that vary widely in coloration, although the most common species in Kansas are dark brown or black and gleam with irridescent hues in the sunlight. The wing covers are relatively short leaving the terminal abdominal segments exposed and, in females, the ovipositor remains extended from the abdomen and is clearly visible.

 

The larvae are yellowish, very elongate, and have three pairs of s The tumbling flower beetle has one generation per year, the adults emerging in spring around the same time as stem weevils. The adults feed mostly on pollen and the females insert their eggs just under the epidermis in sunflower petioles. hort, but well developed, legs at the anterior end. As many as 30 or 40 larvae may reside in the same plant, all distributed in different branches. The larvae live in and feed on rotten wood and plant stems.

 

 

Longhorn beetles (Thyestes gebleri): also known as long-horned or longhorn beetles or longicorns. There are over 26,000 species, more than 1200 of which occur in North America. A number of species mimic ants, bees, and wasps. most are cryptically colored.

 

They range in size from 2 (1/8") to the maximum known body length is just over 16.7 cm (6.6 in). However, these lengths may double or triple when the antennae are included. They have extremely long antennae, often as long as or longer than the beetle's body. However some species have short antennae.

 

Adult beetles feed on leaves, twigs and young bark. Females deposit anywhere from 35 to 90 eggs, one at a time, in pits they dig in the bark. When the eggs hatch, ALB larvae bore into the cambium, the tissue that ferries the tree's nutrients, and then they move into the heartwood. Over several years, this tunneling chokes off a tree's supply of nutrients and kills it—a death by a thousand cuts.

 

The yellowish or white larvae are often known as roundheaded borers, because the front part of the plump larva is expanded to give it a rounded appearance. Using its strong jaws, the larva bores through and feeds in woody plants for one to two years or more. When ready to pupate, the larva bores a tunnel to the outside, pupates within the tree, and, as a new adult, uses this tunnel as its exit. Because of their wood-boring habits, long-horned beetles can be serious pests of timber and pulpwood trees, landscape trees, fruit trees, and woody ornamental plants.

 

 

Weevils (Ceutorhynchus rapae and Rhinocus pericarpius):

 

Ceutorhynchus rapae also known as the Cabbage or hemp curculio. It was accidentally introduced to North America around 1855. Its prim host is cruciferous crops.

 

Young larvae have cylindrical white bodies and brown heads. Older larvae are slightly darker in color, become somewhat plump. They reach 4-6mm in length.

 

Adults are oval to oblong, gray to black and covered with yellow to gray hairlike scales. length 3.5-5 mm.

 

Adults overwinter and emerge in April-May to mate. Females insert eggs into hemp stems when seedling are 3-8cm tall. Only the lower 50cm of mature plants contain grubs. grubs leave exit holes in June to pupate in small cocoons just beneath the soil. Adults emerge in late June-July and feed on the leaves. 1 generation per year.

 

Rhinocus pericarpius also known as the hemp weevil. Live in North America, Europe and Asia.

 

Larvae are white with dark brown-black heads. 4-6mm in length.  Grubs feed within stems and cause small galls. the pupate in stems.

 

Adults are broadly oval, dark reddish-brown to black, thinly covered with grayish-yellow hairs, length 3.5-4mm. Eggs are oval, white, less than 1 mm long. Feed on the leaves and overwinter in the soil.

 

 

Gall midges (Melanogromyza urticivora): 

 

Adults are green and black flies with 2.4-3mm wingspan.  They overwinter as pupae in soil. Adults emerge in spring and lay eggs on host plants. Maggots hatch and bore in cannabis forming galls. It only attack cannabis if nettles (it main host) are near.

 

 

Cactus moth (Cactoblastis cactorum) destroy cactus by burrowing in them. The cactus moth was introduced into Australia from Argentina in 1925 as biological control measure against the prickly pear cactus.

 

The freshwater larvae of Acentropus occur throughout the world, feeding on water plants and either breathing through their skin and tracheal gills or obtaining oxygen from the plants.

 

 

Some caterpillars spoil leaves, seeds, and flowering tops:

 

Cabbage moth Mamestra brassicae: It's a common Palearctic moth. Found in Europe, Russia Palearctic to Japan. Wingspan is 34-50mm. the forwings are brown and mottled with prominent white-edged stigma and a broken white sub terminal line. The hindwings are gray, darker towards the termen. 2-3 generation a year. they are around from May to October. it flies at night and is attracted to light, sugar and nectar-rich flowers.

 

Larva varying in ground colour from green to brown and blackish, with broad pale spiracular line; a dorsal hump on segment.

 

Host plants; onion, columbine, beet, brassica, bryony, marigold, cannabis, chrysamthemum, cucurbita carnation, sunflower, henbane, hyssop, lettuce, flax, maltese cross, tomato, apple, tobacco, pea, plantain, radish, rhubarb, rudbeckia, rumex silene, potato, spinach.

 

 

Silver Y, Autographa gamma: is a migratory moth. wingspan of 30 to 45 mm. The wings are intricately patterned with various shades of brown and gray providing excellent camouflage. In the centre of each forewing there is a silver-colored mark shaped like a letter Y. The species is widespread across Europe, parts of Asia, and North America. Has 2-3 generation a year. The larvae are about 30 mm long, have three pairs of prolegs and are usually green with whitish markings. They feed on a wide variety of low-growing plants and have been recorded on over 200 different species including garden pea, sugar beet, cannabis, cabbage. The pupa are green at first and darken to black. The adults mate one or two days after emerging from the pupa and start laying eggs one to five days later. They die three to nineteen days after emergence.

 

Dot moth, Melanchra persicariae:

 

This is a very distinctive species with very dark brown, almost black, forewings marked with a large white stigma, where it gets its common name. It flies at night in July and August. Its attracted to light, sugar and flowers.

 

Wingspan is 38-50mm. Forewing purplish black; the lines and edges of stigmata blacker; reniform filled up with cream white round a rufous center; submarginal line yellowish white broken up into spots preceded by black wedgeshaped marks; hindwing dirty whitish with broad blackish terminal border; the veins and cellspot blackish; fringe paler. The larvae vary in color, being green, brown or even purplish or pinkish; dorsal line pale; a series of thick green V-shaped marks on dorsum, those on 4, 5, and 11 broader, the 11th segment humped; marked with lighter than the ground color diagonal markings. They overwinter as pupa. Host plants: Aconitum, Actara, Ground-elder, gray alder, columbine, silver birch, heather, campanula, cannabis, creeping thistle, delphinium, hawkweed, touch-me-not balsam, larch,  lupin, yellow loosestrife, petunia, phlox, polygonum, bird cherry, bracken, holm oak, currant, raspberry, rudbeckia, willow, elder, goldenrod, rowan, spinach, tagetes, nasturtuim, nettle, bilberry. 

 

 

Spilosoma obliqua: also know as the jute hairy caterpillar or Bihar hairy caterpillar. found in Afghanistan, northern Pakistan, India, Bhutan, Bangladesh, Burma.

 

Adult are pinkish-buff with numerous black spots. Wingspan is about 23-45 mm. The head, thorax, and ventral side of the body are dull yellow.

 

the female lays more than 400 eggs on the undersides of the leave. the eggs are spherical in shape and light green the hatch 8-13 days. There are 7 instars and pupate in 4-8weeks. full grown caterpillars are stout, about 40mm long, and have 7 orange-colored, broad, transverse bands with tufts of yellow hairs.

 

They skeletonize the leaves when the hatch. mature caterpillars segregate and feed leave including the vines. the prefer older leaves of older plants.

host plants: fruit trees, cannabis, tobacco, pulses, vegetables, potato and sweet potato

 

 

Garden tiger moth, Arctia caja: The garden tiger moth loves damp places, which is why it is particularly common in river valleys as well as gardens and parks. They are nocturnal and attacked to light.

 

The conspicuous patterns serve as a warning to predators, because the moth's body fluids are poisonous. The design of the wings varies: the front wings are brown with a white pattern. the back wings are orange with a pattern of black dots. the moth normally hides its hindwings under the cryptic forewings when resting. If a threat is perceived, the moth quickly shows its red color and flies away. In this way, it successfully confuses and warns off the predator. It has a wingspan of 1.8 to 2.6 inches (45 to 65mm).

 

long-haired caterpillar, on the other hand, is seen more frequently. It can grow up to 6 cm (2.4 in) long and plays dead when in danger. These moths are most common in June to August, in gardens, park, meadows, grasslands, and scrubby areas.

 

Eggs are laid starting in July. Large bluish-white clutches of eggs are laid on the lower surfaces of leaves. The caterpillars hatch in August. They spend the winter on the ground in protected places and pupate from June to July of the following year. The moths hatch from July to August.

 

The caterpillar of the garden tiger moth feeds on various kinds of non-woody plants, as well as bushes and trees. It is especially fond of  raspberry, blackberry, viburnum, honeysuckle, erica, cannabis, broom.

 

 

Beet webworm, Loxostege sticticalis:

 

Manitoba to Texas and westward; sporadic eastward to the New England states. fields, gardens, waste places. They have two generations per year; larvae overwinter in soil and pupate within silken cocoons in the soil in late spring; first generation adults emerge in May.

 

Adult: forewing fringe scales black, contrasting with thin yellowish band along outer margin; ground color yellowish-brown with patchwork pattern of light and dark blotches; PM line very wavy, with a pale area distal to the line where it meets the costa; at rest, outline of moth is triangular. wingspan 24-29 mm. adults from May to September.

 

Larva: pale green when young, becoming olive-green and then black with age; black dorsal stripe with two pale stripes on either side, and two rows of paired circular marks.

larvae to 40 mm. larvae from June to October. larvae feed on wormwood and mugwort (Artemisia spp.), beets, sugarbeets, canola, flax, and spinach

 

 

Beetle grubs and midge maggots also bore into roots and leaves. The former includes the hemp flea beetle (Psylliodes attenuata), a serious pest in eastern Europe and China (Angelova 1968).  The latter are called "leaf miners."  Some leaf miners are beetle grubs (e.g., Phyllotreta nemorum), but most are tiny maggots (e.g., Liriomyza strigata, L. eupatorii, L. cannabis, Phytomyza horticola, Agromyza reptans). To learn more about about Leafminers, click the link: http://freemygreenpdx.com/topic/14919-pest-leaf-miners/?p=125415

 

 

The most serious root pests are flea beetle grubs

 

Hop Flea Beetle,(Psylliodes attenuata

 

Body length, 1.8-2.6 mm. Body oblong-suboval, moderately convex, bronze-green with reddish apical part of elytra. Frontal furrows are deep and distinct, forming a criss-cross between eyes. Antenna 10-segmented, reddish-brown, its apical segments slightly darkened. Elytra without humeral callus, elytral striae are deep and distinct, interstriae fine punctuated. Hind tibia weakly curved, its apex covered with equal spinules. Hindtarsus insertion located proximally of the apex of tibia. The first tarsomere of the hindtarsus is straight from the side view and longer than the second one.

 

Eggs are suboval, light yellow. Egg develops in 6-20 days; optimal soil humidity for embryogenesis is about 40%.

 

Larva has 3 instars and develops in 21-42 days. Usually larva feeds on roots of Cannabis sp., Humulus sp., Urtica sp., often injuring underground part of the stalk. It consumes lateral roots and gnaws furrows on the main root.

 

Pupation occurs inside the soil cradle; its development lasts 6-34 days. Young beetles emerge usually in August. At that time adults consume apical leaves and immature seeds of hemp. Diapause begins in September-October.

 

Mature larva length is about 3.5 mm. Larval 9th abdominal tergite with 10 long setae; its apical margin is rounded. Beetles gnaw numerous holes on leaves, sometimes skeletonizing them entirely. Adults survive after frost about -25°C. Overwintered beetles appear in March-April. They are light-requi Before hemp sprout appearance, they feed mainly on hop and nettle. Sometimes they are marked on tomato, potato, beet, flax, burdock, absinth, and frost-blite. After the temperature falls, the adults concentrate on the soil surface and damage stems. Mating begins after the short period of additional feeding. Female lays eggs in soil around host plants at a depth to 8 cm. Fertility is about 300 eggs. ring insects preferring fields and meadows with moderate arid conditions.

 

Japanese beetles (Popillia japonica) It is not very destructive in Japan due to natural predators, but in North America (first found in 1916) it is a serious pest of about 200 species of plants, including rose bushes, grapes, hops, cannabis, canna, crape, myrtles, birch trees, linden trees, etc. It is thought the beetle larvae entered the United States in a shipment of iris bulbs prior to 1912, when inspections of commodities entering the country began.  It damages plants by skeletonizing the foliage, that is, consuming only the leaf material between the veins, and may also feed on fruit on the plants if present.

 

It is about 15 millimetres (0.6 in) long and 10 millimetres (0.4 in) wide, with iridescent copper-colored elytra and green thorax and head. It is a clumsy flier, dropping several centimeters when it hits a wall. Japanese beetle traps therefore consist of a pair of crossed walls with a bag or plastic container underneath, and are baited with floral scent. The beetle's life cycle is two years long as a result of the higher latitudes of the grasslands required for the larval stage, the white grubs can be identified by their V-shaped raster pattern.

 

 

Chafers (Melolontha hippocastani) from Northern Ireland. These insects can damage huge areas of broadleaf trees and conifers. The larvae feeding on roots and of the adult beetles feeding on leaves.

 

The forest cockchafer is a close relative of the familiar may bug or common cockchafer, and is a large brown beetle which readily flies in spring. size (20-25 mm), and in the shape of its pygidium or tail which is short and more swollen at the end. being solid, broad and brown-colored with darker head and pronotum, and covered with a dusting of greyish pubescence. As with all chafers the antennal club has lamellate or plate-like segments.

 

The adult is mainly recorded in early summer. The grubs develop in the earth for some four to five years, growing continually to a size of about 4–5 cm, before they pupate in early autumn and hatch as a cockchafer after about six weeks. The adult does not come out of the soil immediately but stays there until warmer weather when it digs its way to the surface. Once a year, the female lays up to 30 eggs from which larvae (grubs) hatch that feed underground on the roots of trees during their three- to five-year larval stage.

 

Common Cockchafer, M. melolontha,   also called common cockchafer, May bug, Maybug,  May beetle, June Beetle, May-June Beetle, June Bug, the Spang beetle or the Billy witch. From the U.K. They have unusual fanned antennae. Common cockchafer males can easily be distinguished from the females by counting the number of 'leaves' on their remarkable antler-like antennae, males sport seven ‘leaves’ while females have only six. These leafy antennae can detect pheromones, enabling males to find females in the dark. The wing cases are reddish brown. Cockchafers range in size from 20 - 35 mm.

 

The female can lay as many as 80 eggs about 15 cm below the soil surface. eggs are laid around June - July. Hatching into a white grub which lives underground. Grubs can spend 3 years underground (up to 5 years in colder climates). As grubs they munch on roots and tubers until they reach around 4cm. They have a shiny brown head and legs, with a dirty white body. The larvae are sometimes called rookworms as rooks are supposedly fond of eating them.  they pupate in an oval cell about 60 cm deep in the soil. Pupation takes a month, emerging as an adult beetle in the spring. They live as adults for a mere six weeks.

 

 

 

Minor root pests include:

 

Root maggots (Delia platura), The bean seed fly or seedcorn maggot is a small dipterous insect. It is a sporadic pest with cosmopolitan distribution on germinating seeds of many agronomic plants. Also known as the cabbage maggot fly (Delia radicum) and the onion maggot fly (Delia antiqua), but it becomes active earlier. Previous names for this insect include: Hylemya platura, Hylemya cana, Hylemya cilicrura, Hylemya similis and others.

 

It is the most widespread occurring on all continents except Antarctica. They can have up to five generations per year.  The time required to grow from egg to adult is three to four weeks, and a mean temperature of 74 °F (23 °C) for at least 24 to 25 days is required for completion of the life cycle.

 

The eggs are white, elongated, 1/16 in (0.16 cm) long, and deposited in loose groups among the debris and around plant stems near the soil surface. The flies mate within two to three days after emerging, and each female lays an average 50-200 small, white eggs in plant stems right at the soil line or in cracks in the soil near plant stems.

 

The eggs hatch after two to four days at temperatures as low as 50 °F (10 °C). Females lay eggs near food resources. This pest is closely associated with organic matter such as manure and plant residues.

 

The legless larvae (maggots) are dirty white with a yellow tint, cylindrical and tapered in shape. Fully grown maggots are 1/5-1/4 in (0.50-0.63 cm) long and have a pointed head with two black mouth hooks. The abdomen is blunt with two brown to black spiracles at the posterior end. The larval period lasts nearly 21 days. and the maggots develop over a large temperature range: 52 °F to 92 °F (11 °C to 33 °C). They complete their entire development within the soil by burrowing into seeds or feeding on cotyledons emerging from seeds.

 

The pupa are 3/16-1/4 (0.48-0.64 cm) in long, dark brown to black, barrel shaped, and found in the soil near roots. The pupal stage requires at least 10 days until adults are ready to emerge. They survives the winter in the pupal stage in soil, and adults emerge in early spring

 

Adults (1/5 inch long) are brownish-gray to dark gray flies that look like the common housefly with three stripes on their back, only smaller.  hey are half the size of a house fly, approximately 3/16-1/4 (0.48-0.64 cm) in long. Adults are very numerous in the spring (two to three generations), but their population starts decreasing substantially in mid-summer. In the southern United States, adults are found commonly in the fall, early winter, and spring seasons, but few have been reported in mid-summer. adults die when the temperature exceeds 84 °F. hide under wood and other sheltered habitats to avoid high temperatures.

 

Host plants: alfalfa, cotton, strawberry, hemp, cannabis, tobacco, wheat,

 

Ants (Solenopsis geminata),

 

Although they don’t directly injure your marijuana plants, they can indirectly cause problems within your garden. The mounds of soil they create for their home can negatively impact your plants’ taking in of nutrients and water, and it can reduce the quality of the soil itself. This can hurt the roots. The ants aren’t innocuous as they’re creating nests in your planting medium. Ants are aphid, scales, and white fly ranchers. Sugar ants are extremely small while carpenter ants can be as big as half an inch long.

 

 

Indian White Termites (Odontotermes obesus), pest of wood products and crops like cereals, sunflower or sugarcane in western Asia. The termite forms mounds which may reach 50 cm in height and 100 cm in circumference. The alates are about 30 mm long with wings, while soldiers have a length of about 5 mm

 

 

Fungus gnats (Bradysia sp.)

 

http://freemygreenpdx.com/topic/14427-pest-fungus-gnats/

 

 

Wireworms (Agriotes lineatus).   Commonly known as “click beetles”.  This species is the Lined click beetle. Their name comes from the clicking sound they make while attempting to right themselves after falling or being placed on their backs. The larvae of click beetles are called wireworms.

 

Host plants: firs, onion, garlic, sugarbeet, rape, cabbage, turnip rape, carrot, sunflower, Jerusalem artichoke, barley, hop, lettuce, flax, lupins, tobacco, spruces, pea, grasses, polyphagous, peach, hemp, cannabis, rye, tomato, potato, clovers, wheat, grapevine, corn.

 

Adults are 8-10 mm long. It is distinguished from all other Nearctic species of Agriotes by the very uneven elytral intervals resulting from the pairing of the striae. Adult beetles emerge from the soil in the spring. From late May through June, the female beetles lay 200 to 1400 eggs in loose or cracked soil and under lumps of soil. Females of many species are attracted to lay eggs around grasses. The young wireworms hatch and begin feeding on roots or germinating seeds.

 

Wireworms are long, slender, and yellowish in color, with wirelike hard-bodies. They have three pairs of legs behind the head, and the last abdominal segment is flattened. Full-grown larvae may reach a length of 0.4-1.5 inches (1 to 4 centimeters). The larval stage lasts anywhere from 1 to 5 years, depending on the species involved. When full grown, usually in July, the larvae pupate in the soil. The adults do not emerge until the following spring. Wireworms overwinter as larvae deep in the soil.

 

 

 

Life cycle

 

For European corn borer

 

The corn borer moth is about one inch long with a one-inch (25 mm) wingspan. Female moths are beige, light yellowish-brown to dusky yellow, with irregular olive-brown bands running in wavy lines across their wingspan.  The tip of its abdomen protrudes beyond its closed wings. Females are strong flyers, seeking host plants to lay eggs. Males are smaller and darker. 

 

They lay up to 500 eggs in 25 days.  Eggs deposited on lower leaves of the most mature hosts on undersides of leaves, stems, or crop rubble. Eggs laid in groups of 15-50.  Whitish-yellow to translucent eggs overlap like fish scales.   Eggs are less than 1 mm long and 0.75 m in width. As the larvae develop inside their eggs, the eggs become more and more transparent and the immature caterpillar black or brown heads are eventually visible within the creamy white eggs. The caterpillars hatch by chewing their way out of the eggs. The developmental threshold for eggs is about 59F (15°C). Eggs hatch in four to nine days. There are many reports that weather influences European corn borer survival. Heavy precipitation during egg hatch, for example, is sometimes given as an important mortality factor. Low humidity, low nighttime temperatures, and heavy rain and wind are detrimental to moth survival and oviposition. However, during a 10-year, 3-state study, Sparks et al. (1967) reported no consistent relationship between weather and survival.

 

The young larvae feed externally on the host plants, later boring into the stalks, leaves, stems, and ears. Young larvae tend to feed initially within the whorl, especially on the tassel. When the tassel emerges from the whorl, larvae disperse downward where they burrow into the stalk and the ear.

Mortality tends to be high during the first few days of life, but once larvae establish a feeding site within the plant survival rates improve.  Young larvae (caterpillars) eat leaves until half grown (through the third instar).  Within one or two weeks of boring into small branches, ECBs tunnel into main branches and stalks.  Their bore holes extrude a slimy mix of sawdust and frass (their poop).  Bore holes predispose plants to fungal infection.  Their tunnels may cut xylem and cause wilting.  Stalks at tunnel sites may swell into galls, which are structurally weak, causing stalks to snap. Caterpillars are light brown to pinkish gray with dark brown to black head.  Yellowish-brown spot-like plates run along the length of their bodies, each sprouting a hair-like body.  The developmental threshold for larvae is about 51F (11°C).

 

Mature caterpillars may grow 15-25 mm. long.  Larvae feed for about three weeks, then spin cocoons and pupate.  They spin flimsy cocoons and transform into reddish-brown torpedo shaped pupae (10-20 mm long).  Mature larvae overwinter in crop rubble near the soil line.  Springtime feeding begins when temperatures exceed 15F.  Larvae pupate for two weeks and then emerge as moths in late May (or June or even August in Canada).  Full-grown larvae and pupating caterpillars found in the stalks of the host plant in spring emerge during the summer as yellowish-brown moths. Moths emerge, mate, and repeat the life cycle.

 

A hard freeze late in the year kills all but the most mature larvae (those in their fifth instar).  One to four generations arise each year.  Summers with high humidity and little wind favor egg-laying, egg survival, and larval survival. ECB larvae born in late summer or autumn will change tactics—instead of boring into stems, they infest flowering tops, wherein they spin webs and scatter feces.  They selectively feed on female flowers and immature seeds.  Losses can be as high as 40%.

Ninety one percent of ECB galls are located in the lower  part of Cannabis plants.  Avoid planting cannabis near corn fields.  Cover glass/greenhouse vents with screens and no lights at night.

 

For Hemp Borer

 

HB overwinter as last-instar larva in crop stubble, weeds and sometimes stored seed. they pupate in April, in soil under plants.

 

Eggs hatch in 5-6 days at 71-77F (22-25C), or 3-4 days at 78-82F (26-28C). Out of 350-500 eggs, its estimated only 147 larvae survived to first instar. Decrease of humidity to 40% causes death of 80% of eggs.

 

After hatching, young larvae skeletonize leaves or leaf mine on lower side near ribs. From 2nd instar, they gnaw holes in leaf petioles and in stalks at hemp growth stage of 4-5 leaves for several days before the caterpillars creep upward along stalks, gnawing new holes into petioles, branches and stalks. This feeding within branches and stalks cause fusiform-shaped galls and splitting. Branches and stalks may snap at galls, although the length of tunnels within galls averages only 1 cm or at most 2 cm. Boring near the terminal shoot may kill the shoot and cause branching at that point. Borers pupate within stems. Sometimes 20-50 caterpillars simultaneously feed on one plant. Duration of their feeding is 21-33 days. Caterpillars of summer generation develop one month.

 

Pupation of caterpillars of summer generations occurs mainly in stalks, seeds, and braided leaves. Development of pupae lasts 16-22 days. some caterpillars pupate in cocoons in ground depending on temperature. Pupation begins at 70F (10.4°C). Late-season larvae pupate in curled leaves within buds, bound together by strands of silk.

 

In warmer regions two or more generations occur per year.  Last-instar larvae that overwintered, pupate in April, in soil under plant debris-crops stubble, weeds, and sometimes stored seed.. Moths of 1st generation fly from early-May to the end of June.  They migrate at night to new hemp fields. Once finding a hemp field, females land quickly, usually within 9.8 feet (3m) from the fields edge. After mating, females lay between 350-500 eggs. Adults live less than 2 weeks. Moths are not strong fliers.

 

Caterpillars of 2nd and 3rd generations gnaw holes in small stalks, eat away buds, flowers, and especially seeds. Second generation from July to the last third of August.  Flight of moths of the 2nd generation coincides with the growth stages of flowering and formation of seeds. The generations overlap, and all stages of the Hemp Moth development meet during the vegetation period. 

 

Caterpillars of the 3rd generation, from the end of August to the last third of September, eat mainly seeds. Having no time to finish their development before harvesting, the usually perish. late-season larvae that hatch in the autumn will feed on leaves, flowers and seeds, hence the common names 'hemp leaf roller' and 'hemp seed eater'. The larvae spin loose webs around terminal buds, especially the seed clusters of female plants. The seed eaters destroy young seeds.

 

The majority of caterpillars diapause by the end of August to October under the influence of seasonal change of daylight hours. Day length under 14 hours and temperature influences diapause- warm weather slows photoperiodic effects.   At least 22 hymenopteran species parasitize on the Hemp Moth, killing up to 38.5% of caterpillars and 14.5% of pupae.

 

 

photo_12_16.JPG

 

ECB

 

Host plants:

 

The general rule is as long as the stem of the plant is large enough to give shelter and soft enough for the larvae to burrow into then it is a possible host.

 

The European corn borer has been found a very wide host range on more than 200 host plants, but corn is a preferred host. It is more commonly a pest of corn in Midwestern states, whereas losses in Pennsylvania field corn due to ECB are variable depending on historical infestation levels, weather conditions, and management. Instead, economic levels of ECB damage in Pennsylvania occur more commonly in sweet corn, peppers, and snap beans; however, occasional moderate damage in corn occurs in some southern Pennsylvania fields. Previous research in Pennsylvania suggested that corn borer was responsible for about a 5.5% yearly yield reduction in field corn. Sweet corn, popcorn, and seed corn are the second most affected plants by ECB. In North Carolina, for example, potato is more attractive than corn at peak emergence of the first moth flight, and more heavily damaged. However, the eastern species accounts for most of the wide host range, the western species feeding primarily on corn. Vegetables other than corn tend to be infested if they are abundant before corn is available, or late in the season when senescent corn becomes unattractive for oviposition; snap and lima beans, pepper, and potato are especially damaged.

 

In addition to corn, crops likely to suffer damage include barley, beans, millet, oats, cotton, Irish potatoes, hops, sorghum, hemp, gladioli, wheat, tomatoes, snap beans, peppers,  rice. cannabis, potatoes, giant ragweed, grasses, vegetables, fruits, flowers, cannabis,  cotton, grain sorghum, peppers, beans, Artemisia vulgaris foxtails, pigweeds, smartweeds,  barnyardgrass, cocklebur, dock, jimsonweed, panic grass, aster, cosmos, dahlia, gladiolus, hollyhock, and zinnia.

 

Some plants that have been reported to be infested with ECB but cannot host the larva through their lifecycle include apples, chrysanthemum, lima bean, soybean, black-eyed pea, small grains, sorghum, tomato, onion, and sage.

 

HB Larvae can be pests on marijuana or hop (Cannabaceae) and have also been recorded on knotweed (Polygonaceae).

 

 

First signs:

 

 

Stem boring caterpillars do their damage from the inside of the plant so, they can go undetected until it’s too late and the harm is done. Hemp Borer damage often is in the top 1/3 of plants, while European corn borers usually form galls in the lower 3/4 of the plant.

 

ECB and other boring caterpillars drill longer tunnels than hemp borer larvae. Weevils, curculios, and gall midges also bore into stems and form galls. Late-season hemp borers that infest buds may be confused with late-season budworms. They leave an entry hole at the base of the stalk where they continue chewing through the stems of your plant. a brown trail of death will follow the path of the borer. They cause severe enough damage to water transportation systems of plants everything around the trail dies. If the base of branches or the main stem of the plant are infected, death can quickly follow for everything outwards of the trail.

 

It takes is about five to ten caterpillars to demolish your plant. What’s even worse is that the hole ECB carve into the stems creates an open doorway for other pests that will complete suck the life out of your cannabis plants.

 

When you are checking your outdoor grow, closely take a look at all the stems of your plants, observe the plants stems to see if there are holes with brown trails around them. If you notice visible holes on your plant, then you most likely have a problem. If you find these holes in your stems, the chances are pretty high that you have a serious problem. The only thing you can do at this point is to remove all the parts of the plant, where you have found these holes.

 

Seeds-  external and internal feeding, empty grains, and webbing.

 

Inflorescence (the complete flower head of a plant including stems, stalks, bracts, and flower) may have black fungal spores, distortion, and signs of external feeding. these is a signs of the HB.

 

Chew marks on the leaves and growing points

 

Yellowing on the top leaves

 

Holes with brown trails around them and damage to the stems. For HB there are galls and signs of internal feeding like discoloration.

 

 

photo_10_22.JPG

 

ECB

 

How it spreads:

 

Evidence suggests the pest was imported from its native range via infested hemp seed.

 

What to do For preventative use

 

Lucky for us since the ECB decided it liked corn 200 years ago, there has been many studies on controlling them.

 

Butterflies usually lay their eggs on leaves, so the newly born caterpillars have something to eat after they hatch. Oftentimes, butterflies prefer to lay their eggs in the higher parts of the plant depending on species. For ECB, the lower 3/4 of the plant. HB, top 1/3 of the plant.

 

These eggs are tiny, but you can use a magnifying glass, or the pocket microscope, every grower should have at least one. The eggs look like a small cluster of dots that can be yellow or white in color. Shapes are ranging from round to oval. This depends a little bit on the individual butterfly species.

 

When it comes to stem borers the only way to really get rid of them is to cut them out of the plant. The stem then needs to be banded back together after. Another organic option is to stick a needle in at regular intervals along the stem. The needle will hopefully hit and kill the larvae inside. Bacillus papillae is a beetle specific fungal powder and can have limited success. If the beetle is in the main stem of your plant, injecting a product called rotenone directly into the stalk with a hypodermic syringe will kill the grub.

 

If the plant doesn’t revive itself, then completely remove it by doing a clean cut at the bottom of the train. This will guarantee no further damage. Often times, damage is already done when a borer is located. If the branch or affected area does not bounce back quickly or is obviously done for, remove it with clean scissors/shears.

 

Controlling weeds and grasses in and around the grow site is the most useful preventative measure available. There are two important times when this method is most effective. First, mow or burn surrounding grasses and weeds in mid-August. This will reduce locations for the adults to lay eggs, which overwinter. Another good time to burn down or mow weeds is during the early spring just before eggs hatch. It is important to make sure that eggs have not hatched though because mowing or burning will force the surviving larvae out of the weeds and into the neighboring crops.

 

Neem oil spray is excellent for caterpillar control. Use this once the sun has gone down or on an overcast day. The sun will make the solution useless. Spraying the tops and base of the plants.

 

Nocturnal light traps catch adults is useful for scouting. Using female sex hormones to attract and trap male moths, preventing reproduction.

 

For indoors, Keeping your grow room clean is the only countermeasure.

 

Insecticides

 

Since the borer lives inside the stalks, it makes sprays nearly useless. Your only chance for this method to work is before they bore, but odds are this window will be missed.

 

Biological control

 

Native predators and parasites exert some effect on European corn borer populations, but imported parasitoids seem to be more important. Birds and small mammals are among the natural predators of the borer. Avian predators such as downy woodpecker, Dendrocopos pubescent (Linnaeus); hairy woodpecker, Dendrocopos villosus (Linnaeus); and yellow shafted flicker, Colaptes auratus (Linnaeus) have been known to eliminate 20 to 30% of overwintering larvae.

 

Insect predators often eliminate 10 to 20% of corn borer eggs.

 

Among the native predators that affect the eggs and young larvae are the insidious flower bug, Orius insidious (Say) (Hemiptera: Anthocoridae); also known as minute pirate bugs.

http://freemygreenpdx.com/topic/14336-beneficial-bug-pirate-bugs/

 

Green lacewings, Chrysoperla spp. (Neuroptera: Chrysopidae)

http://freemygreenpdx.com/topic/14337-beneficial-bug-green-lacewing-larvaeeggs/

 

Ladybugs (Coleoptera: Coccinellidae)

http://freemygreenpdx.com/topic/14338-beneficial-bug-ladybugs/

 

Exotic parasitoids numbering about 24 species have been imported and released to augment native parasitoids. About six species have successfully established. Among the potentially important species is Lydella thompsoni Herting (Diptera: Tachinidae), which may kill up to 30 % of second generation borers in some areas, but has disappeared or gone into periods of low abundance in other areas. Other exotic parasitoids that sometimes account for more than trivial levels of parasitism are Eriborus terebrans Gravenhorst (Hymenoptera: Ichneumonidae), Simpiesis viridula (Hymenoptera: Eulophidae), and Macrocentris grandii Goidanich (Hymenoptera: Braconidae).

 

Many native organisms heavily parasitize the hemp borer larvae in the US. 75% of larvae infested by Lixophaga variablis, a tachinid fly, and Macrocentrus delicatus Cresson, a braconid wasp. Goniozus species attack the hemp borer larvae. Scambus species parasitize 30% of hemp borers.

 

Trichogramma wasps to control the 1st generation with 51-68% efficiency. Parasitic wasps Tachinid, Gymno chaeta ryficornis, Braconids, Apanteus papaipemae and Meteorus leviventris, an Inchneumoid, Lissonota brumnea and a Eulophid, Sympiesis viridula.

 

Caterpillar Parasites (Trichogramma species)

http://freemygreenpdx.com/topic/14468-beneficial-caterpillar-parasites/

 

Chalcid wasps (Chalcidoidea Order Hymenoptera)

http://freemygreenpdx.com/topic/14503-beneficial-parasitoid-wasps-chalcidoidea-order-hymenoptera/

 

Parasitoid wasp- General/ multiple species

http://freemygreenpdx.com/topic/14456-beneficial-parasitoid-wasp/

 

Praying mantis

http://freemygreenpdx.com/topic/14335-beneficial-bug-the-praying-mantis/

 

Predatory nematodes can help control grubs in the soil but this is a preventative measure. You can also try injecting stem galls with nematodes. 

http://freemygreenpdx.com/topic/14383-beneficial-predatory-nematodes/

 

 

Spined soldier bugs (Podisus maculiventris)They preys on young hemp borer feeding on the leaf.

http://freemygreenpdx.com/topic/14834-beneficial-bug-spined-soldier-bugs/

 

Several microbial disease agents are known from corn borer populations. The common fungi Beauveria bassiana and Metarhizium anisopliae are sometimes observed, especially in overwintering larvae. The most important pathogen seems to be the microsporidian Nosema pyrausta, which often attains 30% infection of larvae and sometimes 80 to 95% infection. It creates chronic, debilitating infections that reduce longevity and fecundity of adults, and reduces survival of larvae that are under environmental stress.

 

 

What the corn industry is doing for ECB with corn:

 

Bt corn, a variety of genetically modified maize, has had its genome modified to include a gene from the Bacillus thuringiensis. As a result, the corn variety produces a toxin which affects the corn borer.

 

Immature maize shoots accumulate a powerful antibiotic substance, DIMBOA that serves as a natural defense against a wide range of pests and is also responsible for the relative resistance of immature maize to the European corn borer.

 

 

 

 

 

The link below will take you to "An Intro to beneficial bugs and beneficial insect food" it has a list (been worked on) to pests and beneficial insects

 

  http://freemygreenpdx.com/topic/14334-an-intro-to-beneficial-bugs-their-food-and-the-pest-they-take-care-of/

 


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Classy, sassy, and a bit of a smart assy

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