Palm Problems Key - Leaves (canopy)
Entire Canopy (most or all leaves):
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Wilting
a. fungal conk (basidiocarp) present on trunk
Ganoderma butt rot
FACTSHEET: http://edis.ifas.ufl.edu/PP100
b. no fungal conk on trunk
1) older leaves dying and hanging against trunk; leaves may first become chlorotic or discolored; symptoms primarily on ‘Malayan Dwarf’ coconuts
lethal yellowing
FACTSHEET: http://edis.ifas.ufl.edu/PP146
2) top of root system is not found within top 6 to 12 inches of soil
palm planted too deeply
FACTSHEET URL: http://edis.ifas.ufl.edu/EP263
3) soil is water-logged
poor soil aeration
FACTSHEET: http://edis.ifas.ufl.edu/EP263
4)cross-sections of trunk show rotting or discoloration of wood (determined after palm is cut down)
a) discoloration confined to lowest 4 feet, usually concentrated in the center of trunk
Ganoderma butt rot
FACTSHEET: http://edis.ifas.ufl.edu/PP100
b) trunk discoloration with dark fibrous appearance concentrated on one side of trunk
Thielaviopsis trunk rot
FACTSHEET: http://edis.ifas.ufl.edu/PP143
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Necrotic leaves w/ erect canopy
palm dies within a few months;
palm is Syagrus romanzoffiana or Washingtonia robusta
Fusarium Wilt
FACTSHEET URL: http://edis.ifas.ufl.edu/pp278
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Leaves reduced in size
a.leaves uniformly light green or yellow in color
nitrogen deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP268
b. leaves chlorotic and necrotic
late stage potassium deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP269
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Canopy growth in sharp angle to trunk axis
boron deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP264
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Canopy topless from trunk,usually wiwthout warning, rotted, black fibers
Thielaviopsis trunk rot
FACTSHEET: http://edis.ifas.ufl.edu/PP143
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Collapse of almost all leaves in canopy (more than wilting)
a. rapid (1 to 7 days) collapselightning damageFACTSHEET: http://edis.ifas.ufl.edu/EP263
b. moderately fast (more than 2 weeks) to slow collapse of crown (months)1) longitudinal-section through crown area shows crumbly trunk tissue (actually insect frass) and possibly ¾ to 1 inch long gray caterpillars
Opogona (banana moth) larvae damage
FACTSHEET: IP-24.pdf
2) longitudinal-section through crown reveals galleries packed with frass, sometimes with creamy white grubs, cocoons or pupae; most common in Sabal palmetto or Phoenix canariensis, especially if stressed
palmetto weevil damage
FACTSHEET: http://edis.ifas.ufl.edu/IN139
- Leaves tattered
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Leaflets missing or partially missing from leap tips
boron deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP264 -
Chlorosys or necrosys of distal portion of leaves close to high voltage power lines
powerline decline
FACTSHEET: http://edis.ifas.ufl.edu/EP263
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Leaves uniformly light green
Nitrogen deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP268 -
Spotting on leaves
A. Uniformly-colored necrotic spots accompanied by leaflet tip necrosis
Foliar spray toxicity
FACTSHEET: http://edis.ifas.ufl.edu/EP263
B. “spots” not raised; variable in size and in color from yellow to black; most common on small, immature palms.
Leaf spot diseases
FACTSHEET: http://edis.ifas.ufl.edu/PP142
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Leaf bases (and often dead leaf blades) covered with light salmon-pink spores
Gliocladium blight
Most severe on oldest (lowest) leaves:
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Chlorosis (shades of yellow)
a. One or more older leaves uniformly yellow to yellow-orange in color (yellowed leaves may originate mid-canopy in some cases)
lethal yellowing
FACTSHEET: http://edis.ifas.ufl.edu/PP146b. Chlorosis confined to margins of leaves or leaflets; central portion of leaves or leaflets distinctly green
magnesium deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP266
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Leaves discolored, but not necessarily chlorotic; usually shades of red to dark brown or gray
a. palm is a Phoenix species (other than P. roebelenii)
lethal yellowing
FACTSHEET:http://edis.ifas.ufl.edu/PP146 or
Texas Phoenix palm decline http://edis.ifas.ufl.edu/PP163b. palm is not a Phoenix species.
lethal yellowing
FACTSHEET: http://edis.ifas.ufl.edu/PP146 -
Leaflets have translucent yellow/orange or necrotic spotting or yellow-orange discoloration
potassium deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP269 -
Leaflets of oldest living leaves are necrotic on one side of rachis only (or only some leaf segments necrotic if it is a fan palm) and petiole/rachis has reddish-brown to brown or black streak and vascular discoloration evident in cross-section of petiole.
a.palm is Phoenix species
Fusarium wilt
Petiole (Rachis) Blight (all Phoenix species)
FACTSHEET: http://edis.ifas.ufl.edu/PP139
http://edis.ifas.ufl.edu/PP145
b.palm is Syagrus romanzoffiana or Washingtonia robusta
1) palm rapidly declines (a few months)
Fusarium Wilt
2) palm declines very slowly
petiole (rachis) blight
FACTSHEET URL: http://edis.ifas.ufl.edu/PP145
2) palm declines very slowly
petiole (rachis) blight
FACTSHEET URL: http://edis.ifas.ufl.edu/PP145
Note: In most cases, only a diagnostic laboratory can separate a Fusarium disease (Fusarium wilt or Fusarium decline) from petiole (rachis) blight.
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Tip or marginal leaf or leaflet necrosis
water stress
Note: This situation often requires leaf nutrient analysis, soil analysis, or knowledge of plant environment or management history to differentiate between these problems.
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Chlorotic and/or necrotic gray, brown, or black “spotting”
a. very small (<1/16 inch) raised “spots” (actually fungal structures); primarily Phoenix spp.
Graphiola leaf spot (false smut)
FACTSHEET: http://edis.ifas.ufl.edu/PP140
b. raised black, diamond-shaped “spots” (1/8 to 1/3 inch) (actually fungal structures), often accompanied by leaflet tip necrosis; (only on Washingtonia filifera in California and Arizona)
diamond scale
FACTSHEET: Click Here
c. spots are not raised
leaf spots (other than above)
FACTSHEET: http://edis.ifas.ufl.edu/PP142
potassium deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP269
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Gummy exudates (“bleeding”) from multiple small 5 to 8 mm (1/5 to 1/3 inch) wounds in palm leaf bases; galleries in leaf petioles
silky cane weevil damage (Metamasius)
FACTSHEET: http://edis.ifas.ufl.edu/IN210 -
Old to middle-aged leaves have necrotic “skeletonized” patches with only veins and surface layers of leaf intact; underside of leaf necrotic patches typically covered in tubes of insect frass
palm leaf skeletonizers
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Leaf kinks and hangs parallel to trunk
a. leaf remains healthy
wind damageFACTSHEET: http://edis.ifas.ufl.edu/EP263
b. leaf dies; multiple small 5 to 8 mm (1/5 to 1/3 inch) wounds in leaf base
silky cane weevil damage (Metamasius)
FACTSHEET: http://edis.ifas.ufl.edu/IN210 -
More lower leaves dead than normal; upper canopy leaves may be wilted
Ganoderma butt rot
FACTSHEET: http://edis.ifas.ufl.edu/PP100Palm is a Phoenix species (other than P. roebelenii)
lethal yellowing
FACTSHEET: http://edis.ifas.ufl.edu/PP146
or
Texas Phoenix palm decline http://edis.ifas.ufl.edu/PP163
Palm problems youngest leaves:
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Spear leaf (youngest unopened leaf) discolored or collapsed
a. spear leaf hanging down, but does not pull out of bud
1) palm otherwise healthy
boron deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP264
b. spear leaf pulls easily out of bud
1) on cold-damaged palm
secondary bacterial bud rot
[Note: cold damage occurred weeks prior to bud rot symptoms]
FACTSHEET: http://edis.ifas.ufl.edu/PP144
2) non cold-damaged palm
a) lowest leaves healthy
Phytophthora bud rot | Thielaviopsis bud rot
FACTSHEET: http://edis.ifas.ufl.edu/PP144
b) lowest leaves discolored brown or gray; Phoenix spp.
lethal yellowing
FACTSHEET: http://edis.ifas.ufl.edu/PP146
Texas Phoenix palm decline
FACTSHEET:
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No new leaves emerging
a. rest of leaves still mostly green
bud rot (bacterial, Phytophthora or Thielaviopsis)
non-pathogenic bud dama (physical damage to bud as might occur during a hurricane)
FACTSHEET: http://edis.ifas.ufl.edu/PP144b. lowest leaves brown; upper leaves green; palm is Phoenix sp.
1) lethal yellowing
FACTSHEET: http://edis.ifas.ufl.edu/PP1462) Texas Phoenix palm decline
FACTSHEET: Texas Phoenix palm decline http://edis.ifas.ufl.edu/PP163 -
New leaves chlorotic
a. necrotic streaking present
manganese deficiency
FACTSHEET URL: http://edis.ifas.ufl.edu/EP267
1) no necrotic streaking present
iron deficiency
FACTSHEET URL: http://edis.ifas.ufl.edu/EP265
2) green spots on chlorotic new leaves
iron deficiency
FACTSHEET URL: http://edis.ifas.ufl.edu/EP265
3) leaflets of chlorotic new leaves becoming necrotic and palm is Roystonea sp.
royal palm bug damage
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New leaves reduced in size, but older leaves full-sized.
A. new leaves mostly necrotic
1) leaflets curled or frizzled; leaflet necrosis more severe towards base of leaf
manganese deficiency
FACTSHEET URL: http://edis.ifas.ufl.edu/EP267
2) leaflets not curled or frizzled
pre-emergent herbicide injury (Figs. 53a & 53b)
FACTSHEET URL: http://edis.ifas.ufl.edu/EP263
B. new leaves not necrotic, but crumpled and greatly reduced in size
boron deficiency
FACTSHEET URL: http://edis.ifas.ufl.edu/EP264
C. new leaves have truncated tips
1) all leaflet tips truncated (Cocos nucifera only)
manganese deficiency
FACTSHEET URL: http://edis.ifas.ufl.edu/EP267
2) distal leaflets truncated in inverted “V” shape
boron deficiency
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New leaves have sharply hooked leaflet tips
boron deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP264
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Spear (and often other new leaves) fail to open normally
boron deficiency
FACTSHEET: http://edis.ifas.ufl.edu/EP264
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Transverse puckering or transverse translucent streaking on leaflets.