Peach Tree question

Discussion in 'Gardening & Plant Propagation' started by MsPacMan, Aug 25, 2005.

  1. MsPacMan

    MsPacMan Well-Known Member

    Messages:
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    Joined:
    Dec 30, 2004
    Location:
    Tennessee
    I have a small peach tree orchard.


    Today I went back there to cut the grass, and I found one plant with a peculiar problem I have never seen on peach trees before.


    It looked from a distance like a branch of the tree was embedded in thick spider webs, but when you got closer, you could see that there were many worms embedded in the white thready mess, plus a butterfly or two. It was killing the branch it was on (I pruned that branch from the tree).


    What is this problem?


    And aside from pruning the branch off the tree (which is already done), what can I do about it?


    I have a bunch of fruit treees back there, 30 feet from one another, so I really don't want this problem spreading to other trees.
     
  2. skruzich

    skruzich Well-Known Member

    Messages:
    873
    Joined:
    Jul 23, 2003
    Location:
    Georgia
    You know what somethings wrong, I answered this question for you last night.

    Now my replys are missing. I am going to try it again. :)

    IF the web is on the branch enclosing the branch towards the ends, it is the
    Fall Web Worm. Here is some information on it.

    Plants Attacked

    Fall webworm larvae have been known to feed on over 85 species of trees in the United States. Pecan, walnut, American elm, hickory, fruit trees and some maples are preferred hosts in the most of Ohio. Persimmon and sweetgum are also readily attacked in southern Ohio while willow, cottonwood, and alder is only occasionally attacked.
    Damage

    This pest usually eats leaves late in the season and the nests are generally concentrated to limited areas. Because of this, little real damage is done to most trees. However, the nests can look very unsightly and multiple generations in long summers can lead to significant defoliation.
    Description and Life Cycle

    The large silk webs enclosing tips of branches are sure signs of fall webworms. The caterpillars remain inside the webbing, and if food runs out new foliage is encased. The caterpillars are covered with long white to yellowish tan hairs. Two races of fall webworms occur in North America, the blackheaded and redheaded races. The blackheaded race has caterpillars which are light greenish-yellow to pale yellow with two rows of distinct black tubercles. The redheaded race is more tan in color with orange to reddish tubercles. Both races are found in Ohio. The caterpillars make distinct jerking movements in unison if the nest is disturbed. The adults are about one inch long and range from pure white to white with a few black spots.

    This pest overwinters in the pupal stage. Pupae are usually in the ground but can be located in old nest remains, under loose bark and in leaf litter. The adults emerge from late May into July. The eggs are usually deposited in a single (blackheaded race) or double (redheaded race) layer of several hundred eggs on the undersurface of leaves. The mass is lightly covered with scales from the female's abdomen. The eggs hatch in about a week and the small mass of caterpillars web over single leaves and feed by skeletonizing. As the caterpillars grow, they web over additional leaves and finally are able to eat the entire leaf. The larvae mature in about six weeks, at which time they drop to the ground to pupate. The moths emerge over an extended period in two generations can normally be completed in Ohio. In southern states, adults can emerge in mid-March and up to four generations can be completed.
    Control Hints

    Though the webs are very unsightly, damage to most trees is considered to be insignificant. However, in southern states where several generations of attack can severely defoliate trees, control measures are needed. This pest tends to go through periodic population explosions. Outbreaks every four to seven years may last for two to three years and then natural control agents greatly reduce the activity.

    Strategy 1: Mechanical Control - Removal of Nests - Small nests can be pruned out of small to medium trees. Monitor trees early to detect the nests when only several leaves are involved. These small nests can be easily crushed. Do not burn or torch the nests in trees as this may do additional damage to the tree.

    Strategy 2: Biological Control - Encourage Predators and Parasites - Over 80 species of parasites and predators have been identified in North America. Social wasps (yellow jackets and paper nest wasps), birds, predatory stink bugs and parasitic flies and wasps are the most important. Delay destruction of wasp nests until August when social wasps change from carnivores to sugar feeders. Try to withhold contact insecticide sprays until it is certain that predators and parasites are not present in sufficient numbers to control the webworms.

    Strategy 3: Biological Control - Apply Bacillus thuringiensis (Bt) - The bacterial insecticide, Bt, is quite effective against fall webworms if it is applied when the larvae are small. Use formulations with UV protectants and thoroughly cover leaves next to nests. As these leaves are incorporated into the nest and eaten, the Bt will be ingested.

    Strategy 4: Chemical Control - Standard Insecticide Sprays - Most applicators attempt to "blow" the nest out of the tree with a strong jet of insecticide mix. While this generally works, more material is often used than is needed. Locate nests early and merely wet the nest and cover nearby foliage. As the larvae walk on the nest surface or incorporate new foliage, they will contact the insecticide. Second applications may be needed if additional generations occur. See Bulletin 504 for currently registered insecticides.

    Strategy 5: Chemical Control - Use Systemic Insecticides - Extensive nests may occur in tall trees which are difficult to spray with ground equipment. These trees can often be treated with translocated systemics applied to the soil for root uptake or injected. See Bulletin 504 for currently registered insecticides.
     

  3. skruzich

    skruzich Well-Known Member

    Messages:
    873
    Joined:
    Jul 23, 2003
    Location:
    Georgia
    IF the webs are in the trunk of the tree in a crotch of a branch, then that is the Eastern or Forrest Tent caterpillar.


    The eastern or forrest tent caterpillar makes its nest in the fork of branches and does not inclose leaves like the fall webworm. Tent caterpillars are generally active until early June and fall webworms are active in July through September.

    Plants Attacked

    The eastern tent caterpillars prefer wild cherry along roadways, but it can be found making nests in ornamental apple, crabapple, plum, peach, and cherry in landscapes. Occasionally it will form nests in ash, birch, willow, maple, oak and poplar. The favorite food of the forest tent caterpillar is also wild cherry but oaks, maples, hawthorns, and many other shade and forest trees may be attacked.
    Damage

    One or two colonies can completely defoliate small trees. Periodic, major outbreaks result in numerous colonies in larger trees which can also do considerable defoliation. Since this defoliation occurs early in the season, the plants must set out new leaves at considerable energy expense.

    Besides making a tree look unsightly with the webs it constructs in the crotches of limbs and branches, the caterpillars arouse much concern among area residents when they migrate in mass in search of new food or a place to complete their development. During periods of migration, caterpillars may be seen by the thousands traveling over roads, streets, driveways, and sidewalks

    Description and Life Cycle

    The eastern tent caterpillar is easily identified when it builds its white silk nest in the crotch of small trees or where several limbs meet on larger trees. Eastern and forest tent caterpillars have thick, tan hair and are black in color with irregular blue and white mottling. Some of the white markings define stripes. The eastern tent caterpillar has a diagnostic solid white stripe down the back while the forest tent caterpillar has a series of keyhole-shaped spots.

    Tent caterpillars overwinter in the egg stage. Egg masses are attached to small twigs and appear as a shiny, dark gray foam rapped around the twig. These masses are about one inch long and contain 150 to 350 eggs. The eggs hatch in early spring just as the leaf buds begin to show green. The tiny black caterpillars sun themselves on the egg mass but soon move to a nearby fork in the branches. Here they begin to spin silk and form a tent. The larvae migrate to the new leaves to feed, usually in the morning or early afternoon. After feeding the larvae return to the nest. The larvae lay down silk trails wherever they go and these trails serve as roadways for other larvae. Feeding continues for four to six weeks until the larvae are about two inches long. Mature larvae usually leave the nest and tree to search for a suitable place to spin a cocoon. The larvae spin compact, spindle-shaped cocoons of white to yellow silk. The adults emerge in two to four weeks. The adults are about one inch long, are reddish brown in color and have two creamy-white stripes running obliquely across the front wings. Forest tent caterpillars do not make a nest and the adults moths have dark brown stripes instead of white. Mating occurs soon after emergence and the females attach their new egg masses to tree branches. These masses stay on the tree until the following spring. There is only one generation per year.
    Control Hints

    People often get overly concerned when they see large numbers of nests in roadside wild cherry. Fortunately these pests rarely reach large populations in ornamental trees.

    Strategy 1: Mechanical Control - Destroy Egg Masses and Nests - The egg masses are easy to spot after the leaves have dropped in the fall. Simply clip off and crush or dispose. If egg masses were undetected, there is ample time to hand remove any nests in the spring. It is suggested that a glove be used as the caterpillar hairs are irritating to some people. Simply scrape the nest off onto the ground and crush the caterpillars or drop them into a pan of soapy water. Early morning or late afternoon is best because most of the caterpillars will be in the tent.

    Strategy 2: Biological Control - Use Bacillus thuringiensis (Bt) - Most commercial Bt products for caterpillar control will work on the tent caterpillars. Make applications to the plant foliage while the larvae are small. Numerous predators and parasites also attack this pest but in some years these agents do not arrive in sufficient numbers to adequately control tent caterpillars.

    Strategy 3: Chemical Control - Insecticide Sprays - Most contact and stomach insecticides rapidly control this pest. Direct sprays to the plant foliage and nest. The larvae are usually easy to contact if spraying is done in late morning when the larvae congregate on the tent surface to warm in the sun. See Bulletin 504 for currently registered insecticides.
     
  4. skruzich

    skruzich Well-Known Member

    Messages:
    873
    Joined:
    Jul 23, 2003
    Location:
    Georgia
    One more thing, it referrs to a list, if there is a referrence to restricted use pesticide, you cannot get the pesticide unless your licensed to use it and to obtain it.

    Steve
     
  5. Lararose

    Lararose Adams Nebraska

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    Aug 6, 2005
    Location:
    82 acres SE Nebraska
    I have a crabapple tree in front of my house that has gotten them in the past two years. Last year I pruned them out and this year I read online that you can take a garden rake and gently remove them. I tried that this year and shook them into a soapy bucket of water to kill them and it worked great! I could reach up the tree alot farther too! You have to make sure that the time of day is right when most of them are congregated in their web nest and not traveling the branches to feed, but you can easily see that.