Lepidoptera is an order of insects that includes moths and butterflies (both called lepidopterans).
180,000 species of Lepidoptera are described, in 126 families[1] and 46 superfamilies.

Some (Sycamore Borer shown) will feed on trees bark, plants leaves and stems while 

  others will cause serious damage even death to plants.

They are one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies. The term was coined by Linnaeus

Lepidoptera show many variations of the basic body structure that have evolved to gain advantages in lifestyle and distribution and is among the four most speciose orders, along with the Hymenoptera, Diptera, and Coleoptera

Lepidopteran species are characterized by more than three derived features, some of the most apparent being the scales covering their bodies and wings, and a proboscis. The scales are modified, flattened “hairs”, and give butterflies and moths their extraordinary variety of colors and patterns.

Like most other insects, butterflies and moths are holometabolous, meaning they undergo complete metamorphosis. Mating and the laying of eggs are carried out by adults, normally near or on host plants for the larvae.

The larvae are commonly called caterpillars, and are completely different from their adult moth or butterfly forms, having a cylindrical body with a well-developed head, mandible mouth parts, and from none to 11 (usually eight) pairs of prolegs. 

As they grow, these larvae change in appearance, going through a series of stages called instars. 

Once fully matured, the larva develops into a pupa, referred to as a chrysalis in the case of butterflies and a cocoon in the case of moths. A few butterflies and many moth species spin a silk case or cocoon prior to pupating, while others do not, instead going underground.

White pine root decline is a serious disease on pines for a number of years before the causal agent was first described in 1962 as Verticicladiella procera.
The genus Verticicladiella belonged to a complex of morphologically similar genera known as the Leptographium-complex. The genera Leptographium and Phialocephala also formed part of this complex.
The three genera in the complex were distinguished on the basis of their respective modes of conidiogenesis.
Species in Leptographium were characterized by annellidic conidium development, whereas species in Verticicladiella and Phialocephala were characterized by sympodial and phialidic conidium development, respectively.

Disease symptoms caused by L. procerum have been described under several different names. The first of these was White Pine Root Decline, which occurs on Pinus strobus and in Christmas tree plantations where it can reach epidemic proportions.
This disease was also known as Leptographium root decline, white pine wilt and white pine root disease before it was suggested that the name Procerum root disease should be used.
Red pine decline disease on Pinus resinosa has also been attributed to L. procerum infection.

White pine root decline was first reported in eastern USA and L. procerum was later found to be consistently isolated from diseased trees. However, the role of the fungus in causing this disease has been a matter of considerable debate. The disease is commonly referred to as a root decline but in most cases manifests itself as a wilt  The symptoms of the disease are similar to those caused by infestation by the root-collar weevil (Hylobius radicis), for which it can be easily mistaken.

Hosts and species affected;
Abies fraseri (Fraser fir), Abies grandis (grand fir), Picea abies (common spruce), Pinus banksiana (jack pine), Pinus clausa (sand pine), Pinus contorta (lodgepole pine), Pinus echinata (shortleaf pine), Pinus elliottii (slash pine), Pinus monticola (western white pine), Pinus nigra (black pine), Pinus palustris (longleaf pine),Pinus pinaster (maritime pine), Pinus ponderosa (ponderosa pine), Pinus radiata (radiata pine), Pinus resinosa (red pine), Pinus strobus (eastern white pine), Pinus sylvestris (Scots pine), Pinus taeda (loblolly pine), Pinus thunbergii (Japanese black pine), Pinus virginiana (scrub pine), Pseudotsuga menziesii (Douglas-fir)

List of symptoms/signs
Growing point – wilt, Leaves – wilting, Leaves – yellowed or dead, Roots – rot of wood, Stems – discoloration
Stems  –  gummosis or resinosis, Stems – internal feeding, Stems – mould growth on lesion, Whole plant – plant dead; dieback, Whole plant – wilt

Glycaspis spp. (psyllid), G. brimblecombi (redgum lerp psyllid)

 Psyllids are plant‑juice sucking Homoptera in the insect family Psyllidae. During its nymphal (immature) stage, this type of psyllid forms a protective cover called a “lerp”, which makes older nymphs look similar to armored scales. However, unlike scale coverings, the lerp is composed mostly of crystallized honeydew, the sugary water that homopteran insects excrete, and resemble small white, roundish caps on leaves that grow up to about 1/8 inch (3 mm) diameter and 1/12 inch (2 mm) tall. The nymph underneath each lerp is yellow or brownish and looks similar to a wingless aphid. Older nymphs stay beneath their lerp and generally don’t move. Adult lerp psyllids are slender insects that are about 1/8 inch (3 mm) long. Their bodies are light green with orangish and yellow blotches and they have clear wings that are usually held rooflike over their abdomen. The adults differ from other psyllids found in California in that they have relatively long forward projections (called genal cones) on each side of their head below their eyes. Females lay tiny, yellowish, ovoid eggs, singly or in scattered groups.

 Amoung their host plants are River red gum (Eucalyptus camaldulensis) is a primary host of red gum lerp psyllid (hence the name) and sugar gum (E. cladocalyx). Other species of lerp-producing psyllids attack many other species.

 They are found in Australia, California and any place eucalyptus are growing.

 As with other psyllids, redgum lerp psyllid develops through gradual metamorphosis, which includes the egg, several increasingly larger nymphal stages, and the adult. There is no pupal stage. Females prefer to lay their eggs on succulent leaves and young shoots, so population increases often follow the production of new plant growth. However, all psyllid life stages can occur on both new and mature foliage. Young nymphs may be observed excreting gelatinous honeydew from their rear end. Older nymphs are concealed beneath their lerp. In its native Australia, the psyllid has 2 to 4 generations a year, and a similar number of generations would be expected in California. Development time from egg to adult varies from several weeks during warm weather to several months during prolonged cool temperatures. In mild coastal areas, all stages can be present throughout the year.

 Look for White, roundish caps on leaves that grow up to about 1/8 inch. High populations of psyllids secrete copious amounts of honeydew. A blackish sooty mold grows on the honeydew‑covered surfaces. High psyllid populations can cause severe leaf drop. Extensive defoliation weakens trees and increases tree susceptibility to wood‑boring pests such as longhorned beetles.

Synanthedon pictipes
Lesser peachtree borer is an important pest in peach and cherry orchards

Problems are almost always associated with widespread incidence of Cytospora canker and, to a much lesser extent, pruning wounds, winter injury, and mechanical damage.

Adults are day-flying moths that resemble wasps. Veins and margins of transparent wings are fringed with steel-blue scales; the body is blue and narrowly fringed with yellow. Males of lesser peachtree borer have yellow scales on the top of the head between the eyes and black scales between the antennae.

The damage to trunk and limbs can be seen by wads of sap dripping from them called “Gumosis”.

This combination differentiates them from peachtree borer males, which have black scales between the eyes and yellow scales between the antennae. Lesser peachtree borer larvae are white with a yellowish brown head and reach 1 inch at maturity.

There are two and possibly a partial third generations each year; the first flight occurs during May and June, and the second during August and September in the east.

The borer overwinters as larvae and reaches full growth during April and May. Larvae eat an exit hole nearly through the bark, spin a cocoon, and pupate in a small cavity. In 3 to 4 weeks, a clearwinged moth emerges, leaving an empty pupal skin projecting from the burrow.

Adults are active for several weeks. The female moth is capable of laying several hundred eggs in cracks, under bark scales, and in cankered areas. Moths are attracted to trees that have been injured or previously infested. Eggs hatch in a week to 10 days, and young worms move to the inner bark and continue to feed.

Magnesium is present in the soil, where it is usually  present as magnesium sulfate. It is very soluble, which leads to deficiencies commonly occurring in wet soils.

Magnesiumas a the key element in the chlorophyll molecule and funtions as a carrier for phosphorus, and is most abundant in those regions of the plant where rapid growth occurs, such as the tips of stems and roots.

Broadleaf symtoms:
Magnesium deficiency vary with plant species and time of symptom development, but chlorosis develops generally or as streaks or bands, and leaf drop is the end result. Late stages may result in marginal or  tip necrosis. Lower leaves may remain a deep green.
Conifers symtoms:
Include moderate chlorosis, mainly in the upper crown. Lower portions of crown and crown tips may remain deep green.

Manganese is found as a salt in the soil.
Manganese serves with iron in the manufacture of chlorophyll.  It may also aid in nitrogen assimilation and synthesis of protines.  A deficiency of manganese also disturbs carbohydrate metabolism, and results in chlorosis and retarded growth.
Broadleaf Symptoms:
Leaves are often chlorotic with wide green bands along their veins with necrotic interveinal pots appear and the leaves may become limp. Shoot growth stunted. Fruits are often smaller than normal.
Conifers Symptoms:
Are similar to symptoms of iron deficiency with new growth being stunted and chlorotic. Older needles and the lower crown will remain green.

Planococcus citri (Risso), Pseudococcidae, Homoptera

The female adult is wingless and appears to have been rolled in flour . It grows to 3 mm long and 1.5 mm wide. A fringe of small waxy filaments protrude from the periphery. The males are small, but with its wings and tail filaments, it appears to be 4.5 mm long. It’s eggs are oblong, yellow eggs are enmeshed in a dense, fluffy, white ovisac. The crawler are tiny and oval and yellow, with red eyes. The antennae are rather rather distinct. Female nymphs resemble the larger adult females. Male nymphs are narrower and often occur in a loose cocoon.

Citrus mealybugs occur in southern Europe and in the southern United States, where they overwinter outdoors. Further north, they survive in interiorscapes and homes.

Citrus mealybugs have been collected from at least 27 host plant families. Many ornamental plants grown in interiorscapes are susceptible to attack.

Mealybugs damage hosts by sucking out plant sap, by excreting honeydew in which sooty mold can grow, and by causing distorted growth and premature leaf drop with their toxic saliva. They further disfigure plants by secreting cottony wax. Infested plants usually die unless the pest is controlled.

The mealybug has been recognized as a pest of citrus and ornamental plants in Europe since 1813 (where it is called the greenhouse mealybug) and in the United States since 1879. Because female mealybugs have no wings, they must be transported to the proximity of the next host plant. They can, however, travel short distances by crawling and the immatures can be blown about. Males are small, winged insects. After mating, each female lays up to hundreds of eggs in a dense, fluffy secretion called the egg sac or ovisac. Within a few days, new mealybugs (crawlers) hatch and begin to squirm out of the ovisac. Light infestations are easily overlooked because the mealybugs tend to wedge into crevices on the host plant.

Melanconium betulinum   (fungus)

All birch are suseptable.

Found throughout United States and Canada.

Borer infestation, drought, poor soil drainage, adverse temperatures (over 95^o F.), exposed locations, and sandy soils all contribute.

There is a Progressive browning of foliage and dieback of twigs and branches from flattened, sunken, swollen and discolored cankers. Diseased bark on branches red-brown, dotted with cupped, black fruiting bodies.

Acervulus are embedded in outer bark, hyphae extending into cambium. Conidia are released to invade bark through natural openings (lenticels), where new acervuli develop. Infection continuous during growing season.

MIMOSA WEBWORM (Homadaula anisocentra Meyrick)

The mimosa webworm feeds primarily on the leaves of mimosa and honeylocust trees. It was unintentionally introduced from China into the United States during early 1940s. This pest was first reported in Washington, D.C. During this same period improved (thornless) varieties of honeylocust, Gleditsia triacanthos, were planted as replacements for American elms killed by Dutch elm disease in these landscapes. This decision may have led to the spread of mimosa webworm and possibly other key pests of honeylocust.

DESCRIPTION:
At maturity larvae are about 16 mm long, grayish to dark brown and have five white stripes running the length of the body. The head is brown and the body is slender. They are very active and, if disturbed, will wriggle and lower themselves on silk strands. The 6 mm long yellowish brown pupae are found within whitish silken cocoons.
It is rare to see an adult. They are steel-gray moths with small black dots on their forewings. Adults have a 13 mm wingspan. The eggs are very small, oval, and white that turn a rose color just before hatching.

HOST:
Honeylocast:
Sunburst seems to be the most susceptible to webworm attack. Other varieties including
Shademaster, Skyline, Moraine and Imperial are less susceptible but still subject to severe injury.
Mass plantings of any of the thornless varieties should be avoided

LIFE CYCLE:
Mimosa webworm has two generations per year.

The first generation is usually small in number and easily overlooked. The greenish, brownish, or grayish slender larvae feed on the leaflets of honeylocust and mimosa (silk tree). When disturbed, mimosa webworm larvae move quickly and violently, which helps them escape. The first-generation larvae web together two or three leaflets and feed on the leaflet undersides. This feeding causes the leaves to appear silvery at first, particularly from a distance. As damaged areas dry, they turn brown. Large numbers of first-generation infestations scattered throughout a tree call for an insecticide application to reduce the more seriously damaging second generation.

First-generation caterpillars pupate in the webbed leaves and emerge as small grayish moths. These moths mate and tend to lay eggs back into first-generation webbing. The second generation is usually much larger in number than the first. These caterpillars typically web together two to six compound leaves, causing damage that is much more obvious. Although treatment of the second generation is usually successful, considerable damage may have occurred before treatment is initiated.

Fully grown second-generation caterpillars migrate out of the webbing to pupate in protected areas such as under loose bark on tree and shrub trunks and under building siding. Many webworms pupate under siding and around windows of heated buildings where temperatures are a few degrees warmer–which explains why higher populations of mimosa webworms are found in trees near heated buildings and in years following mild temperatures.

DAMAGE:
The larval stage of this pest is the most damaging life stage. As larvae feed, they spin a web around leaflets and continue to feed within this protected area. The foliage appears skeletonized, turns brown, and then may die. If left alone, an infestation may progress and completely defoliate a tree by early September. Often an entire plant may be webbed by September. Mature larvae are sometimes a nuisance as they silk down and get into homes and other dwellings.

Mountain Pine Bark Beetle, Dendroctonus ponderosae, and
Western Pine Beetle, Dendroctonus brevicomis

These species of bark beetles are native to the forests of western North America from Mexico to central British Columbia.
It is one of the most significant of all other conifer/pine bark beetles as they have the ability to destroy large portion of conifer forests.

They have a hard black exoskeleton, and measures approximately 5 mm, about the size of a grain of rice.
In western North America, the current outbreak of the mountain pine beetle and its microbial associates has destroyed wide areas of lodgepole pine forest, including more than 16 million of the 55 million hectares of forest in British Columbia. The current outbreak in the Rocky Mountain National Park began in 1996 and has caused the destruction of millions of acres of ponderosa and lodgepole pine trees. According to an annual assessment by the state’s forest service, 264,000 acres of trees in Colorado were infested by the mountain pine beetle at the beginning of 2013. This was much smaller than the 1.15 million acres that were affected in 2008 because the beetle has already killed off most of the vulnerable trees (Ward).[1]
Attacking ponderosa, whitebark, lodgepole, Scotch, jack pine, and limber pine trees and others. Normally, these insects play an important role in the life of a forest, attacking old or weakened trees, and speeding development of a younger forest. However, unusually hot, dry summers and mild winters throughout the region during the last few years, along with forests filled with mature lodgepole pine, have led to an unprecedented epidemic. It may be the largest forest insect blight ever seen in North America.[4] Climate change has contributed to the size and severity of the outbreak, and the outbreak itself may, with similar infestations, have significant effects on the capability of northern forests to remove greenhouse gas (CO2) from the atmosphere.

These beetles develop through four stages: egg, larva, pupa and adult. Except for a few days during the summer when adults emerge from brood trees and fly to attack new host trees, all life stages are spent beneath the bark.
In low elevation stands and in warm years, mountain pine beetles require one year to complete a generation. At high elevations, where summers are typically cooler, life cycles may vary from one to two years.
Female beetles initiate attacks. As they chew into the inner bark and phloem, pheromones are released, attracting male and female beetles to the same tree. The attacking beetles produce more pheromones, resulting in a mass attack that overcomes the tree’s defenses, and results in attacks on adjacent trees.
They affect pine trees by laying eggs under the bark. The beetles also can introduce blue stain fungus into the sapwood that prevents the tree from repelling and killing the attacking beetles with tree pitch flow. The fungus also blocks water and nutrient transport within the tree. On the tree exterior, this results in popcorn-shaped masses of resin, called “pitch tubes”, where the beetles have entered. The joint action of larval feeding and fungal colonization kills the host tree within a few weeks of successful attack, the fungus and feeding by the larvae girdles the tree, cutting off the flow of water and nutrients. When the tree is first attacked, it remains green. Usually within a year of attack, the needles will have turned red. This means the tree is dying or dead, and the beetles have moved to another tree. In three to four years after the attack, very little foliage is left, so the trees appear grey.
As beetle populations increase or more trees become stressed because of drought or other causes, the population may quickly increase and spread. Healthy trees are then attacked, and huge areas of mature pine stands may be threatened or killed. Warm summers and mild winters play a role in both insect survival and the continuation and intensification of an outbreak. Adverse weather conditions (such as winter lows of -40°) can reduce the beetle populations and slow the spread, but the insects can recover quickly and resume their attack on otherwise healthy forests