Hyphantria cunea (moth)

Fall Webworm larvae are blackhead and redhead races vary widely in appearance and habits. Early instars do not wander from web but enlarge it to include new leaves. Late instars scatter to feed on anything green, becoming very destructive. Late instars of blackheads,  yellow-green to pale yellow, covered with fine hairs, later with dark stripe along back, two rows of dark tubercles along back, web and small. Redhead, tawny with orange-red tubercles; web larger and compact. All pass through as many as 11 instars. Damage is more cosmetic than life-threatening to trees.

The adults are white, occasional black spots on wings. Orange markings on body and legs; wing span, 1 1/4 in. long; emerge in May or June. Their eggs are in clusters of several hundred on undersides of terminal leaves. The pupae overwinter in dark brown, flimsy cocoons made of silk and hair from the larval  bodies; in debris, slightly under soil, or attached to tree trunks.

They need 30 degree days at 60° F. and they can infest nearly all deciduous trees.

Fall Webworm are worldwide and are Native to United States; Canada; Mexico.

Terminal branch webs with larvae in webs jerking back and forth when disturbed. They will cause major defoliation of upper crowns in August.

Adults emerge in May-June to lay eggs in clusters on undersides of terminal leaves. Tents are spun and larvae feed from July to mid-September. Timing varies with geographical area.

One to four (1-4) generations per year, four (4) being common on Gulf of Mexico States.

Erwinia amylovora   (bacterium)

Hosts include many species of the rose family, including apple, amelanchier, cherry, crabapple, hawthorn, mountain ash, pear, plum, and pyracantha. Found throughout the continental United States and southern Canada.

Contributors include cool, wet weather or fog; infected nursery stock or grafting stock; overhead sprinkler irrigation; over-fertilization.

In late spring, blossoms, young leaves, and shoots suddenly wilt. Infected areas of tree first appear water-soaked, then quickly turn brown to black, appearing as if burned by fire. The infection may progress down a shoot or small branch and start a stem canker in a larger branch or stem. The inner bark of these cankered areas is water-soaked, turning green to brown. The surface withers and wrinkles. In warm, wet weather, milky ooze may appear on infected bark, attracting insects. Cankers may girdle branches or the main trunk killing the tree. Dead leaves remain attached to dead branches.

The bacterium overwinters at edges of cankers and on blighted twigs, becoming active during warm spring rains. Ooze is produced on twigs and cankers, attracting numerous insects which may carry the pathogen to the foliage, twigs, and blossoms of healthy trees. Bacteria may also be carried by contaminated pruning tools, or by dripping water or splashing rain from the ooze to healthy tissues below. The pathogen generally enters the tree through wounds, natural openings in the leaves, or through flower parts. Infections enlarge until spring growth stops, about a month after blossoming. Bacteria in infected tissues lie dormant in late summer and remains so until the following spring.

Chrysobothris californica (beetle) and many others.
Flatheaded borers egg galleries are laid in bark crevices. The larvae enter the bark where their eggs are laid, boring into inner phloem in irregular tunnels, partially filling them with powdery frass. They may even girdle a young tree.

Their larvae is creamy white, 3/8-1/4 in. long and are black tip at head and tail with a segmented head approximately three times as broad as their body. The adults are Flattened in appearance, 1/8-3/16 in. long and a dark metallic brown.

They infest many hardwood and conifers trees.

Flatheaded borers are found throughout United States, including Alaska including the Hudson Bay region of Canada.

Fire scars, root and trunk injuries, and other injuries causing stress including construction damage are the main factors that contribute to infestations.

Extensive mining of bark and cambium, sometimes girdling stems or roots of young trees; tunnels through sapwood and into heartwood, filled with frass.

Adults emerge from pupal cells in spring or summer, feed for a short time, mate, and lay eggs soon afterward. Eggs hatch in 10-50 days, and young larvae start mining. The larval stage may last for several years. Usually one generation every 1-2 years. Pupal stage generally lasts a month, but pupae may overwinter in some locations. Adults may overwinter in the pupal cell before emergence, or may hibernate overwinter before emerging. Adults die within 1-2 months after emergence.

Fusarium moniliforme var. subglutinans (fungus)

Pine trees susceptible include Bishop, eastern white, loblolly, longleaf, Monterey, sand, Scots, shortleaf, slash, Table Mountain, and Virginia pines.

 Regions affected include, Southeastern United States, California, Texas.

Factors that contribute are, Physical wounding (including lawn mowers, weed-eaters, and climbing spurs), insects (tip moth, midge, bark beetles, deodar weevil) which may serve as vectors, and other fungus infections (eg. gall rust).

 Symptoms of pine pitch canker include, resin-soaked lesions around wounds, girdling twigs and small branches; developing into perennial cankers on trunks and large branches. Bark remains on canker faces. Diseased bark reddish-brown; underlying sapwood is yellow-brown and impregnated with resin. Resin exudes from lesions and cankers to run down bark or onto foliage below. Shoot dieback, tip wilting, and branch incurving (“shepherd’s crook”) follow.

 Macroconidia produced on small, cushion-like, salmon-colored sporodochia (approximately 1/16 in. wide and 1/32 in. high) on dead shoots and twigs, generally on needle fascicle scars. They are present all year, but most evident in autumn and winter. Conidia are colorless, having from 1 – 4 cells, curved, elongate, and pointed; disseminated by wind, insects, and splashing water throughout the year.

Fusarium oxysporum f.sp. perniciosum
Commonly called Mamosa Wilt.
Fusarium wilt is a common and lethal disease of mimosa (Albizia julibrissin), also commonly known as Persian silktree. Mimosa is native from central China to Iran and was introduced in the early nineteenth century to the United States. Fusarium wilt is caused by a member of the Fusarium oxysporum species complex: Fusarium oxysporum forma specialis perniciosum.

Members of the F. oxysporum species complex are cosmopolitan and many cause vascular wilt on many economically significant plants. Albizia spp. are the only known host of F. oxysporum f.sp. perniciosum.

Fusarium oxysporum f. sp. perniciosum colonizes and clogs the tree’s vascular (water-conducting) tissue, which interferes with the movement of water and nutrients. This results in relatively rapid tree death.

A very early symptom of Fusarium wilt is a brown-streaking in the wood beneath the bark and/or the roots; however, these symptoms typically go unnoticed.

The first readily noticeable symptoms are yellowed, stunted, and wilted leaves on one or several branches in early to mid-summer.

Later in the summer the affected branches may prematurely defoliate. Yellowed and wilted leaves continue to appear on more branches throughout the summer and fall, although in some cases a tree may die within a month of initial symptom appearance. Streaks of discoloration in the sapwood are very characteristic for the disease and can be observed by removing the bark on diseased branches or trunk or by observation of a discolored ring of sapwood in a cross-section of a diseased branch. 

As the disease progresses cracks begin to appear in the bark. In some cases, gum or a white, frothy liquid with a fermented odor may exude from cracks. Sometimes a tree survives to the next growing season, but the new leaves will be stunted and yellowed and the tree will continue on a relatively rapid decline toward death. After the aboveground portion of the tree dies roots may still be alive and shoots may continue to sprout from the base of the trunk for some time.

Fusarium oxysporum f. sp. perniciosum is a soilborne fungus. The long-term survival of this fungus occurs by means of chlamydospores in the soil. When roots of host trees grow close to chlamydospores, root exudates are able to stimulate chlamydospores to germinate and produce mycelium. The mycelium then penetrates and colonizes the mimosa roots, moving into the vascular tissue where the fungus begins to produce microcondia.

The microcondia move upward with the tree’s sap and become deposited in various locations in the vascular tissue. Thus, a systemic colonization of the plant’s vascular system occurs. This eventually results in a clogged and defective vascular system.

When the tree defoliates prematurely due to this disease, the fungal pathogen grows out from the vascular tissue into the bark and begins production of pink to orange spore masses within sporodochia in lenticels. Macrocondia are produced in these spore masses. The fungus may continue to produce macroconidia for a period of two years after tree death. The macroconidia can be spread to new locations by air, water and insects; however, the primary means of spread occurs through water which washes the macrocondia into the soil where they germinate and produce chlamydospores. The chlamydospores can be spread to new locations through movement of infested soil or on contaminated equipment, tools, and shoes. The fungus may also persist in seed produced by diseased trees.

Fusarium subglutinans f. sp. pini is an important pathogen of pine that causes pitch canker in mature trees and root rot and damping-off in seedlings.

This fungus can be spread by both infected seedlings and seeds

Much Pathological confussion exists regarding but here is a little information; Fusarium subglutinans f. sp. pini (= F. circinatum) is a pathogen of pine.

Fusarium subglutinans f. sp. pini which causes pitch canker of pine trees. It is a synonym of Fusarium circinatum.
Fusarium subglutinans – Maize, Mango
Fusarium oxysporum – Pine

Laboratory cultures are required to identify the differences in the complex.

We hope you will look closer on what research is available and seek additional expert information.

Fusarium oxysporum   (imperfect fungus)

 Most plants are susceptible to some degree. Most commonly found on alder, bay tree, catalpa, elm, laurel, madrone, magnolia, mimosa, maple, oak, and olive.

This fungus is present in most agricultural, nursery, and landscaped soils.

 Root wounding such as construction damage, transplanting, leaking gas lines, soil compaction. Also, nematodes, soil insects, drought, flooding, sudden heating of soil after cool season, low soil pH, excessive ammonia nitrogen, boron deficiency, low calcium and potassium deficiency are all contributing factors.

The symptoms include wilting or yellowing of some leaves, first on scattered top branches, often causing leaves to hang down. Leaves eventually die and drop. Death to tree usually within 18 months, depending on environmental conditions. Trunk and branches have a red to brown ring of discolored sapwood. Xylem often plugged with brown gum. Small branches may have one-sided wilting with the bark flattened over the collapsing tissue and a slight tendency to turn inward (“shepherd’s crook”).

This fungus is completely soilborne, infection generally arising from hyphae or by germination of two main spore types: microconidia and macroconidia. With its specialized, thick-walled resting spores (chlamydospores), it can survive long periods of unfavorable environmental conditions. In the presence of the proper host, these cells germinate when more moisture and higher temperatures are available.

Callirhytis punctata (cynipid wasp)

Adults are Tiny, 4-winged, yellow to brown. While their larvae are white and legless with several per gall.

They are what is refered to as cynipid wasp andf athe Scarlet, red, pin and black oak.

What contributes to them is not well known.

They are located in the Northeastern U.S. extending to southern Georgia; southern Canada.

Identification is several yellowish, irregularly round galls attached to twigs. Several larvae per gall. Can damage twigs in twig gall stage.

They are Tiny parthenogenic wasps emerge from galls in May and June. Eggs are laid on undersides of leaf veins. Eggs hatch and larvae cause tiny galls on veins, appearing as small oblong blisters in late May and June. A generation matures in July with emergence of both male and female wasps. Upon mating, female lays eggs on young twigs. Galls form the following spring. Two years or more are required for young wasps in twigs to mature

Porthetria dispar   (moth)
Gypsy moth larvae are approx. 1 1/2-2 1/2 in. long with yellow markings on head their bodies are dusky, hairy, with 5 pairs of blue spots on dorsum and a double row of 6 pairs of red spots.

The adult body is slender, dark brown with black bands across forewings; abdomen with yellow hairs. Flight zigzag. Wingspan 2 in. long; large, heavy abdomen prevents flying by females. The eggs numbers are over 400 in chamois-like masses of yellow hairs from female’s body deposited on the undersides of branches, tree trunks, loose bark, in cavities, on fences, stone walls, RV’s, lawn furniture, etc., wherever larvae may climb. The pupae are dark reddish-brown, with scattered red hairs, attached to some object by a few silken threads.

Gypsy moth Preferre Apple, basswood, birch, hawthorn, oak, poplar, speckled alder, and willow.

These trees can be infested but are not preferred hosts; Ash, balsam, butternut, catalpa, cedar dogwood, holly, locust, sycamore, walnut, yellow poplar, fir and many other species.

 Thier geographic areas include United States: East Coast, Ohio, Kentucky, California (traps).Pure stands, egg transport by vehicles, lawn furniture, absence of predators, high winds (which may transport larvae a mile or more) are contributing factors

Defoliation, larvae on silk threads, chamois-like egg masses on undersides of objects and at bases of tree trunks are some of the symptoms observed.

Moths emerge and mate; eggs deposited in July-August. Egg stage overwinters will hatch in early May. First instars spin down tree through 5-6 instars; fully-grown in June-July. Pupal stage lasts 10-14 days.

Pachypsylla celtidivesicula,. celtidismamma
Hackberry psyllids are often called NIPPLE GALL PSYLLIDS because nipple-shaped galls about 3/16 inch wide and 1/4 inch high develop on the underside of infested leaves. They resemble miniature cicadas (about 1/6 inch long) and are a dark, mottled-gray color

The gall, an abnormal plant growth on leaves or stems, results from complex chemical interactions between developing insects and plant tissues. As a gall develops, it becomes a “house” where the immature insect resides. Most infested leaves contain several galls, and host trees apparently do not suffer seriously, although galls are normally considered unsightly.

Adult psyllids emerge from galls in September and can be annoying to people living near infested trees. Psyllids will swarm to houses, particularly light-colored ones, in search of protected locations to pass the winter. They are attracted to lights at night and are small enough to pass through ordinary window screening. In some instances, large numbers gain entry into a home and become a nuisance. Psyllids do not bite people, pets or houseplants — they are pests only because of their unwanted presence.

After the onset of winter, psyllids generally are not active; however, they may mistakenly come out of dormancy on warm winter days and may create a minor nuisance. The biggest nuisance normally occurs during spring, when they break dormancy and fly about indoors, looking for places to exit the structure.