1. University of Florida Extension
Key Plants and Key Pests in North Florida Landscapes Podocarpus, Gardenia, Camellia, and Pyracantha
Rebecca McNair
University of Florida Extension

2. IPM Integrated Pest Management
Natural processes of control are emphasized
Host plant resistance
Pest exclusion
Prevention and through cultural practices
Physical Control
Biological control through natural enemies
Chemical control as a last resort
Tolerance
Monitoring

3. Podocarpus Nageia nagi

4. Podocarpus- Key Pests Diseases Mushroom root rot Other Nematodes
Magnesium deficiency

5. Mushroom Root Rot Slow decline, thinning of canopy Gray-green color
White mycelia under bark at soil line
Armillaria tabescens

6. Armillaria tabescens fruiting body appears in fall.
Root Rot Management
Remove diseased plants and roots
Fumigate soil before replanting
Armillaria tabescens fruiting body appears in fall.

7. Root nodules Beneficial nitrogen-fixing blue green algae
Often mistaken for root knot nematodes
Active nodules have a pink milky fluid in their centers
Hemoglobin within the nodule fixes atmospheric nitrogen. When exposed to oxygen, the fluid inside changes from blue to pink!

8. Roots infected with Meloidogyne are swollen.
Root Knot Nematodes
Endoparasitic nematode
Feeds on root tissues
Dieback, decline, chlorosis
Identify under microscope
Roots infected with Meloidogyne are swollen.

9. Nematode Management Fumigate Solarize soil
egg mass
Fumigate
Solarize soil
Buy plants grafted with resistant varieties
Provide adequate water and fertilizer
Remove and replace plants and soil
Meloidogyne sp.

10. Magnesium Deficiency Management Increase pH with dolomite
Yellow inverted “V”
Occurs on mature leaves
Low soil pH
Lack of soil Mg
Management
Increase pH with dolomite
Apply Epsom salts or Mg fertilizers

11. Gardenia augusta
Acid loving plant
Fragrant flowers

12. Gardenia- Key Pests Diseases Stem Canker Other Nematodes
Manganese deficiency
Environmental stress

13. Stem Canker Sudden wilting Chlorosis Leaf spots
Yellow halo around lesions
Stem cankers
Galls, usually at the soil line
Girdling may occur

14. Stem Canker Management Fungus pathogen enters injured tissue
Spores spread by splashing water
Management
Minimize plant injury
Avoid overhead irrigation
Phomopsis gardeniae
Notice the yellow halo around the leaf spots on this gardenia.

15. Nematodes Roundworms Root Knot nematodes live inside plant roots
All live in liquids, i.e. water in soil
Feed on plant sap
Damage roots
Inhibit growth

16. Decline due to root knot nematodes compared to a healthy gardenia.
Decline and thinning of canopy
Roots brown, stunted and galled
Decline due to root knot nematodes compared to a healthy gardenia.

17. Nematode Management Fumigate Solarize soil
Buy plants grafted with resistant varieties
Provide adequate water and fertilizer
Remove and replace plants and soil
Meloidogyne sp

18. Manganese Deficiency Management Interveinal chlorosis on new growth
Reduced leaf size
Necrotic distortion of new growth
Common in alkaline soils high in phosphorous
Management
Use a complete fertilizer with micronutrients

19. Environmental Stress Management Excessive water or fertilizer
Cold or temperature fluctuation
Nutrient Deficiency
Drought
High pH
Mechanical damage
Management
Correct cultural problems
Provide cold protection
Prune and re-grow
Chlorosis
Bud drop

20. Camellia japonica Acid loving Prefers partial shade
Fragrant flowers from late winter to early spring

21. Camellia- Key Pests Diseases Crown Gall Petal blight Leaf spot Other
Twig dieback
Other
Environmental stress

22. Gall
Galls can appear on any plant part and may be due to bacteria, fungi, nematodes, or insects.
Agrobacterium tumefaciens is a common soil bacterium that causes crown gall disease by transferring some of its DNA to the plant host This has enabled scientists to genetically manipulate plants, a technique called transformation.

23. Petal Blight Irregular, brown spots Dark veins Blighted flowers drop
Prefer warm, moist conditions
Ascospores are spread by water
Fungus overwinters as sclerotia, a hard black structure that remains viable for 5 years
Cibornia camelliae (formerly Sclerotinia)
Sclerotia

24. Cibornia camelliae fruiting body.
Petal Blight Control
Suppress sclerotia development
Remove all infected flowers, leaves, and litter
Promptly burn or bury diseased materials (at least 1 ft deep)
Limit overhead irrigation
Cibornia camelliae fruiting body.

25. Fungal Leaf Spot Management Circular or irregular lesions
Margins raised
Brown - gray
Fungus favors high humidity and partial shade
Management
Limit overhead irrigation
Avoid crowding
Copper fungicides
Cerscospora caloloma

26. Algal Leaf Spot Wide host range
Smooth leathery leaves are more prone to infection
One of the few green algae parasitic on higher plants
Management
Limit overhead irrigation
Cephaleuros virescens

27. Twig Dieback Fungus Summer-winter: cankers Spring:
Young shoots wilt and die
Brown leaves remain on the dead shoots
Glomerella cingulara
Twig dieback and a healthy camellia.

28. Twig Dieback Management Prune infected areas, including cankers
Leaf scars are most common point of entry
Often confused with root rots
Plants can be infected by both
Root rot increases the severity of twig dieback
Management
Prune infected areas, including cankers
Fungicides

29. Environmental Stress High heat and light Temperature fluctuation
Drought
Mechanical damage
Management
Maintain adequate water
Bud Drop

30. Pyracantha coccinea Firethorn Prefers full sun
Will grow in partial to fairly heavy shade
Fast growing

31. Pyracantha- Key Pests
Diseases
Fireblight

32. Fireblight Bacterium New shoots wilt suddenly and die
Dead leaves remain on the shoots
Spread by bees and splashing water
Erwinia amylovora

33. Fireblight Management
Bacteria enter through flowers and infection spreads into the stem
Management
Limit overhead irrigation
Remove infected branches
Use resistant varieties

34. Acknowledgements
Authors: Rebecca McNair Reviewers: Dr. Russ Mizell, Dr. Norman Leppla, Dr. Doug Caldwell, Celeste White, and Christine Kelly- Begazo Funding: Florida Yards and Neighborhoods Photos: Thanks to the Florida Dept. of Agriculture and Consumer Services, Division of Plant Industry, and University of Florida Extension faculty for providing photographs, including:
Dr. James Castner Dr. Catherine Mannion
Dr. Lance Osborne Dr. Avas Hamon
Dr. Norman Leppla Dr. George Agrios
Bill Graves Dr. Doug Caldwell
Holly Glenn Dr. Tim Schubert
Dr. Eileen Buss