Choristoneura fumiferana

The spruce budworm is one of the most destructive native insects in the northern spruce and fir forests of the Eastern United States and Canada. Periodic outbreaks of the spruce budworm are a part of the natural cycle of events associated with the maturing of balsam fir.

The States most often affected are Maine, New Hampshire, New York, Michigan, Minnesota, and Wisconsin. These outbreaks have resulted in the loss of millions of cords of spruce and fir.
Balsam fir is the species most severely damaged by the bud-worm in the Eastern United States. White, red, and black spruce are suitable host trees and some feeding may occur on tamarack, pine, and hemlock. Spruce mixed with balsam fir is more likely to suffer budworm damage than spruce in pure stands.
The range of the spruce bud-worm includes the Northern States east of Montana but the budworm is found wherever host species grow
The light green eggs are about 1 millimeter long by 0.2 millimeter wide. The eggs, laid in elongate masses of 2 to 60 – averaging about 20, overlap one another
The newly hatched budworm larva is very small and difficult to find because it bores into and feeds on needles or expanding buds.
The adult moth has a wing span of 2 centimeters. It is usually grayish with dark brown markings. Some moths are brown or reddish with gray markings. Males and females occur in about equal numbers.

The pupa is pale green at first, later changing to reddish brown. It is marked with darkened bands and spots

Ramosia resplendens (clearwing moth)
The adults have a wingspan of about 1 1/4 in. long; black with yellow bands around thorax, there wings are clear and antennae almost half the body lengthand black.

The eggs are laid singly in small cracks or depressions of trunkand are yellow.

Their larvae are pinkish-white with and have a brown head almost 3/4 in. long at maturity. They bore into inner bark in twisting tunnels over an area about 100 sq.cm. They do not feed on heartwood. They cause the to bark sloughs off above tunnels.

They pupate near exits of tunnels, then loose skin often exposed as it exits after the adults emerge. Frass may exist at tunnel entrances.
Two major California trees are effected by this insect, the Western sycamore and coast live oak (Quercus agrifolia).

They seem to stay around central and Southern California.

Older trees seem to be preferred that are under drought conditions , and wounds.

 Sloughing bark is obvious, often looking like mud on sycamore their are holes with some bleeding on oak; a small amount of frass on trunk or around holes and branch dieback occures.

The adults emerge from May to early August, laying eggs singly in cracks in bark or bark depressions, favoring wounds. Larvae bore into inner bark, feeding while making torturous tunnels. They feed most of the winter and pupate in early spring, at which time adults emerge (usually in May) from the bark.

(Including Sycamore Lacebug)
Corythucha ciliata, C, Ulmui, C. arcuata, C. sp., Stephanitis sp., Kalmia sp.

 Adult lace bugs are about 3 to 6 mm (1/8″- 1/4″) long with a netlike pattern on the wings. In addition, the wings are dotted with brown and black. The immature stages, called nymphs, are similar except they are smaller and often have spines. The eggs, although small, are easily distinguished by their elongate and cylindrical shape. They resemble small black smoke stacks attached to the undersides of the leaf. Lace bugs are in the order Hemiptera, family, Tingidae.

Sycamore, birch, elm, alder, hawthorn, willow, oak, cherry, walnut, linden, poplar, ash, broad-leaved evergreens, many deciduous trees and shrubs are common hosts.

Lace bug damage is first noticed as yellow spots on the upper leaf surfaces of affected plants. Lace bugs actually feed on the undersides of leaves with their piercing-sucking mouthparts, but because they kill surrounding cells as they feed, they cause the yellow spots to appear on upper sides of the leaves. The first yellow spots that appear are very similar to mite damage, but the spots made by lace bugs are much larger. When feeding damage becomes severe, the leaves take on a gray blotched appearance or can turn completely brown. As lace bugs feed they produce brown varnish-like droppings that spot the underside of the leaves. These droppings further distinguish lace bug damage from mite damage. When large numbers of lace bugs are present cast skins can be found attached to the leaves.

 On deciduous plants, adult lace bugs overwinter in protective places on the host, such as bark crevices and branch crotches, or on the ground in leaf litter. They end their hibernation just as spring growth starts. They attach their eggs to the undersides of the leaves often along the mid-ribs, sometimes covering them with a black varnish-like coating. The eggs will stay attached to the leaves long after they have hatched and can be recognized by noting if the tops have openings. The nymphs complete their life cycles quickly and one to several generations can occur in one season. Usually, there are two generations. Some lace bugs can complete a generation in as few as 30 days. On broad-leaved evergreens, lace bugs overwinter as eggs on the undersides of leaves. Eggs hatch in May. Two or more generations may occur during the growing season.

AKA MADRONE DECLINE

Thielaviopsis basicola (fungus)

 Elm and madrone are most affected and is found throughout the United States: including Central California.

Heavy, cold, slightly acid to alkaline soils, well supplied with humus. Soils with pH lower than 5.6 and sandy soils low in organic matter are less conducive to disease development.

Symptoms include root rot leading to yellowing of foliage and dieback of branches; eventually fatal. Basal stem discoloration extends some 6 inches above the soil line.

The fungus lives in the soil saprophytically, typically entering the roots through wounds caused by nematodes. Two types of spores are formed: (1) colorless, cylindrical conidia (phialospores) are arranged in line with a colorless hyphal tip, breaking off one by one into the soil. (2) Dark, thick-walled aleuriospores exposed in chains, eventually breaking apart. These function as resting spores (chlamydospores) capable of resisting unfavorable soil conditions and providing longevity as dormant spores. The spores are picked up by feeding nematodes to be deposited within the host. Or, they may be carried on nematode bodies, eventually entering the roots via germination tubes growing through feeding wounds made by the nematodes.

Are from the Order; Thysanoptera,
Frankliniella occidentalis, Heliothrips haemorrhoidalis, Scirtothrips citri

They are tiny, slender insects with rasping mouthparts. Most are plant feeders that scar leaf or fruit surfaces. Adult thrips are slender and small and tend to feed in buds within furled leaves, or in other unexposed areas of the plant; their damage is often observed before the thrips can be seen. Numerous black specks of feces scattered over a stippled leaf surface is a clue that damage is caused by thrips, but look for the insects themselves.

Many landscape trees are hosts. Thrips can be a serious pest of California pepper tree, ficus, magnolia, dogwood, acacia, grapes, peaches, nectarines and herbaceous plants.

The thrips life cycle includes the egg, two actively feeding nymphal stages, non-feeding pre-pupa and pupa stage, and the adult. Metamorphosis is between gradual and complete. Thrips eggs are kidney- shaped and very large in relation to the female; they are laid within the leaf tissue. Thrips have several generations (up to eight or more) per year. The life cycle from egg to adult may be completed in as short a time as 2 weeks when the weather is warm.

Damage caused feeding by thrips adults or nymphs causes tiny scars on leaves and/or fruit, called stippling , and can stunt growth. Damaged leaves may become papery and distorted. Infested terminals may discolor, become tightly rolled and drop leaves prematurely. Thrips prefer to feed in rapidly growing tissue. Black, varnish-like specks of excrement are a distinguishing feature of thrips activity. Thrips can cause dead spots or blotches to appear on flowers.

OAK DECLINE COMPLEX.
Caused by one or more of the following fungi:
Botryodiplodia querci, Fusarium solani, Cephalosporium diospyri, Pestalotia macrosporum, Diplodia quercina, Phialophora sp., Dothiorella querci, Verticicladiella sp., Fusarium oxysporum, Verticillium albo-atrum

All oak species are hosts.

This complex has been reported throughout the continental United States.

Drought (soil moisture levels below 60% field capacity), with air temperatures above 60° F. Root damage from transplanting, construction, or compaction all contribute.

Symptoms vary according to host and fungus involved. Initial discoloration of leaf margins, sometimes with interveinal yellowing; later total yellowing possible, followed by stunting, slow to quick wilting, and dieback; usually evident first in upper crown. Leaves may or may not fall prematurely. As disease progresses individual branches may have thinner foliage, followed by a thinning of the entire crown. Vascular discoloration varies with organism, red-brown to black-blue, in twigs and/or root crown. Tree may die in as few as 2-3 months, or death may be gradual over 3-8 years.

Lethal infection, generally through roots from soilborne phase of fungus. Some of the fungi (Botryodiplodia, Diplodia) may become established as twig-canker inciters, at which stage decline is slow. Falling branches and twigs may introduce the fungus to the root area.

Verticillium albo-atrum, V. dahliae   (fungus)

Host trees include acacia, ash, aspen, beech, boxelder, black locust, camphor tree, carob, catalpa, dogwood, elm, golden-rain, hickory, horse chestnut, Indian hawthorn, linden, maple, oak, osage orange, olive, persimmon, pistachio, redbud, Russian olive, sassafras, smoke tree, tulip tree, and walnut.

this disease is known to be worldwide.

Heat, dry soil, previously infested soil are all causes.

Some trees (e.g. maple) may wilt suddenly in mid-summer, often with a large branch or one side of tree wilting and drying while the other side remains fresh. Other trees (e.g. camphor tree) wilt at tips of uppermost crowns and slowly die back. Symptoms in elm crowns resemble those of Dutch elm disease, requiring laboratory confirmation. Discoloration of sapwood varies from yellow to green to purplish brown. Slime flux sometimes develops in the bark. The disease can be chronic, with a slow dieback from season to season, the twig tips incurving to produce a “shepherd’s crook,” or it may be acute with severe wilt and death within a single season. Pistachio wilt is characterized by affected leaves hanging from dead branches over-winter, like Fire blight. Progress is slowed by adequate moisture or by high nitrogen fertilizers, such as ammonium sulfate.

This fungus is active at all times, but it is most active in warm, dry soils. It overwinters in soil by sclerotia which germinate with spring moisture to invade fine rootlets. Once inside roots, it moves through the vascular system to the tip of the plant crown, destroying vascular elements as it progresses. It may be transmitted through the soil, by infected pruning tools, or by nematodes. Vehicular tires may spread pathogen from infested soil to non-infested soil.

Dendroctonus brevicomis (beetle)

The larvae are White and curved, the size of a rice grain; feed in inner bark, working away from egg gallery 1/2 in. before turning into outer bark, where they pupate.

Adults are Dark brown to black, 1/8-1/5 in. long. Egg galleries are winding, crossing and recrossing, forming network of irregular markings on inner surface of bark and on surface of sapwood.

Main host include Ponderosa and Coulter pines.

Found from Baja California north into Oregon, Washington, Idaho, Montana, and western Canada.

Favored by Drought, fire and other injuries, nutrient deficiencies, overcrowding, disease and windfalls.

 Bleeding holes in bark like “buckshot” holesare easily noticed if looking closely and discoloration of crown from light greenish-yellow to red. May kill apparently healthy trees of all age classes with bark sufficiently thick to protect insect in its development; trees under 6 in. dbh seldom attacked.

Their flight starts late in spring or early summer, continuing until stopped by cold weather. One to two generations annually in northern range, and 1 1/2 – 4 in southern range where activity continues throughout the year.

WESTERN SPRUCE BUDWORM (Choristoneura occidentalis Freeman)

The western spruce budworm, is the most widely distributed and destructive defoliator of coniferous forests in Western North America. It is one of nearly a dozen Choristoneura species, subspecies, or forms, with a complexity of variation among populations found throughout much of the United States and Canada. It occurs in the Rocky Mountains from Arizona and New Mexico northward into Colorado, Utah, Wyoming, Montana, and Idaho; in the Pacific Northwest in Oregon and Washington; and in British Columbia and Alberta, Canada.

IDENTIFICATION:
Adult moths are about 12.7 mm long and have a wingspread of 22 to 28 mm. Moths of both sexes are similar in appearance, although the females are a bit more robust than males. Both sexes fly. The gray- or orange-brown forewings are banded or streaked, and each usually has a conspicuous white dot on the wing margin. Eggs are oval, light green, and about 1.2 mm long and overlap like shingles.

Larvae develop through six stages. Newly hatched larvae are yellow-green with brown heads. In the next three stages, larvae have black heads and collars and orange- or cinnamon-brown bodies. In the fifth stage, larvae have reddish-brown heads marked with black triangles, black collars, and pale olive-brown bodies marked with small whitish spots. Mature larvae (see cover) are 1 to 1¼ inches (25 to 32 mm) long, with tan or light chestnut-brown heads and collars and olive- or reddish-brown bodies with large ivory-colored areas. Pupae are 13 to 16 mm long, broad at the head end, and narrower toward the tail. They are brownish-yellow or brownish-green at first, and later turn reddish-brown

LIFE CYCLE:
Throughout most of its range, the western spruce budworm completes one cycle of development from egg to adult within 12 months. Moths emerge from pupal cases usually in late July or early August; in the southern Rockies, adults often begin emerging in early July. The adults mate, and within 7 to 10 days, the female deposits her eggs and then dies.
Each female deposits approximately 150 eggs, usually on the underside of conifer needles. Eggs are laid in one- to three-row masses containing a few to 130 eggs, with an average of 25 to 40 eggs per mass. Females usually lay some eggs at the site where they emerge and mate, then disperse to deposit their remaining eggs.
Larvae hatch from eggs in about 10 days. Larvae do not feed, but seek sheltered places under bark scales or in and among lichens on the tree bole or limbs. Here, they spin silken tents called “hibernacula” in which they remain inactive through the winter.
In early May to late June, larvae leave their hibernacula to search for food. They first mine or tunnel into year-old needles, closed buds, or newly developing vegetative or reproductive buds. Larvae usually leave traces of silken webbing and bits of excrement at the feeding site or entrance hole (fig. 6). As new shoots flush, larvae spin loose webs among the needles and feed on the new foliage. As shoots continue to elongate and needles develop, adjacent shoots often are webbed together by the larvae and begin to appear twisted or stunted. New foliage, which is normally the preferred food, is usually entirely consumed or destroyed before larvae will feed on older needles. On some hosts, larvae favor developing male flowers and conelets as food, and on western larch, larvae mine and sever the terminal and lateral shoots.
Larvae become full grown usually in early July about 30 to 40 days after leaving their overwintering sites. As larvae mature, the webbed branch tips on which they have fed begin to turn reddish brown (fig. 7). Larvae pupate in webs of silk they have spun either at the last feeding site or elsewhere on the tree. The pupal stage usually lasts about 10 days.

HOST TREES:
The most common host-tree species of the western spruce bud-worm are: Douglas-fir (Pseudotsuga menziesi (Mirb.) Franco), grand fir(Abies grandis (Doug. ex D. Don) Lindl.), white fir (Abies concolor (Cord. and Glend.) Lindl. ex Hildebr.), subalpine fir (Abies lasiocarpa (Hook.) Nutt.), corkbark fir (Abies lasiocarpa var. arizonica (Merriam) Lemm.), blue spruce (Picea pungens Engelm.), Engelmann spruce (Picea engelmannii Parry ex Engelm.), white spruce (Picea glauca (Moench) Voss), and western larch (Larix occidentalis Nutt.). Larvae feed occasionally on Pacific silver fir (Abies amabillis Dougl. ex Forbes), mountain hemlock (Tsuga mertensiana (Bong.) Carr.), western hemlock (Tsuga heterophylla (Raf.) Sarg.), lodgepole pine (Pinus contorta var. latifolia Englem.), ponderosa pine (Pinus ponderosa Dougl. ex Laws.), western white pine (Pinus inonticola Dougl. ex D. Don), limber pine (Pinus flexilis James), and whitebark pine (Pinus albicaulis Engelm.). Some of these tree species are also hosts of other closely related species of Choristoneura whose populations sometimes occur simultaneously with the western spruce budworm.
Often budworm larvae feed on and seriously damage coniferous trees that are planted as ornamentals, such as Norway spruce (Picea abies (L.) Karst., and Scotch pine (Pinus sylvestris L.).

DAMAGE:
Cones and seeds. – In addition to foliage, budworm larvae feed heavily on staminate flowers and developing cones of host trees (fig. 8). The resultant decline in seed production has a serious impact in seed orchards, seed production areas, and forest sites that are difficult to regenerate naturally. Moreover, artificial regeneration practices are affected because seed is not available for nurseries or direct seeding.
Unlike some cone and seed insects, budworm larvae do not always restrict their feeding to a single cone. Often, second- or third-stage larvae feed on newly developing conelets that soon shrivel up, dry out, and fall from the tree. As these cones dry out and become unsuitable for food, larvae continue feeding on other cones or on foliage.
In some Douglas-fir stands, nearly all cones may be damaged or destroyed by feeding larvae, especially when larval population densities are high and cone crops are light. Top-killing of some host trees, as a result of persistent heavy defoliation, often precludes cone production for many years, even when budworm populations subside.