More Common Tree Problems

Pine Needle Scale:

Chionaspis pinifoia

An invading insect that lays white sacks of eggs, or scales on the needles of pine and spruce trees. Heavy infestations cause Chlorosis to needles and cause dieback and early needle brown-ing. Defoliation can also occur. Once eggs hatch, new insects feed on new growth, causing stunted growth to tree. Scales cover needles in spring and insects hatch in summer. Males are winged and fly to other surrounding trees to further infest.

Time of YearAffected TreesSymptomsRisk
SpringPinesWhite scales on leavesmoderate
SummersprucesDefoliation
Browning needles
gnats

Sapsucker:

Sphyrapicus varius

A migrating bird that feeds on the sap of trees by pecking holes into the trunk of most tree spe-cies in either a horizontal or vertical pattern. If the bird feeds too much on one tree, the above portions of the tree will die and bark will fall off. Once tree bark starts to fall off, the tree is sus-ceptible to other insect infestations. The holes bleed sap that attracts other insects such as ants, wasps, and bees, so many times it may seem as an insect infestation, but the holes indi-cate the sapsucker bird.

Time of YearAffected TreesSymptomsRisk
Early SpringMost tree species¼” holes in treeSevere
SummerPrefers: birch, maple, and hamlockSap flow on branches & leavesfatal

Southern Pine Beetle:

Dendroctonus frontalis

Lives in the inner bark of Florida pine trees. Aggressively kills pines by feeding on phloem tissue. Trees try to defend by counteracting with hundreds of pitch sacks, or resin masses seen as white spots on the outer bark of the tree. Pitch tubes range from whitish-yellow to a reddish-brownish color. This pest attacks below the lowest branch of tree but can reach the base of large branches. Insect spreads through pitch sacks which contain beetle larvae. Once larvae reach adulthood, they burrow through outer bark and fly to another tree up to 2 miles away.

Time of YearAffected TreesSymptomsRisk
SpringSand pineWhite/brown spots on tree trunkHigh
Slash pineFoliage discolor-ationFatal
Loblolly pineCrown of pine changes from green to yellow
Shortleaf pine
Pond pine
Virginia pine
Spruce pine
Spruce pine

Spruce Spider Mite:

Oligonychus ununguis

One of the most destructive pests to conifers, this mite causes bronzing and browning of needles of host trees by feeding on leaves. A dark green to black looking bug, that starts off yellowish when first hatched. Early defoliation occurs often in host trees. Mites usually attack inner needles that are older on the tree. Mites weave small silk webs on branches and needles. Cool seasons are the predominant time of year for hatching. By the time infestation is seen, host trees are usually severely infested and in need of care.

Time of YearAffected TreesSymptomsRisk
SpringMost SpruceRusty looking patches in treeModerate
SummerJuniperEarly defoliation
HemlockSmall silk webs
Most Pines
Douglas-fir
Arborvitae
Caders
Larch

Crown Rot:

A disease caused by an invading organism, fungus, or protist that rots the crown of a plant, where the stems and roots meet. Crown rot is fatal to plants and contaminates soil surrounding host plants. Leaves of host plants will change color, whither, and eventually die. The stem area close to the root, or crown, will turn black and the whole plant will wilt.

Time of YearAffected TreesSymptomsRisk
All yearAll plants, trees, and shrubsBlack crownSevere
Discolored leaves/stemsFatal
Wilting
Withering

Ganoderma Butt Rot:

Ganoderma zonatum

A fungus that rots the lower 4-5 feet of palm trunk. Wilt can occur along with browning of palm leaves and branches. This disease is fatal to all types of palms. Fungus rots wood and disrupts the xylem (water distri-bution) of the affected palm tree, causing death. The fungus enters the palm through spores that spread through the soil and are absorbed through the root system. This disease will move with its host plant if trans-planted, and will infect new trees if the palm is removed and a new palm is installed. It is unknown how long the soil will stay contaminated with spores.

Time of YearAffected TreesSymptomsRisk
All YearAll Palm SpeciesBrowning palm leavesSevere
Wilting leavesFatal
Conks (mushroom) growth on side of trunk
Decaying trunk

Verticillium Wilt:

A soil-borne fungal disease caused by the soil-borne fungi Verticillium dahliae and V. albo-atrum. Contamination comes from soil and causes plants to wilt. Wilting is mostly seen from spring until autumn. Fungus is absorbed into plants through the water system of the plant and clogs vital watering arteries. Clogging of arteries causes plant to release brown/blackish mucus resulting in streaks just under bark. If not treated, plant will die from lack of proper nutrient absorption.

Time of YearAffected TreesSymptomsRisk
SpringChrysanthemum, carna-tion, aubergine , potato,Yellowing and shrivel-ling of lower leavesModerate – severe
Summertomato, cucurbits strawberriesWilting
FallAcer, Cotinus, Rhus, Berberis,Brown/black streaks in tissue under bark
Catalpa, Cercis RosaBranch dieback
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