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Home , Helianthus annuus

3/26/2018

European Pear (Pyrus communis): Fruit distortion due to true bug feeding damage Fraser Photinia (Photinia x fraseri): defoliation by Leaf Spot (Diplocarpon mespili)

Forsythia (Forsythia sp.): Stem Gall (Psudomonas savastanoiBirch ()Betula sp.): gall Oak (Quercus sp.): mite galls

Alder (Alnus rubra): cankers (undetermined cause) (Prunus persica): dieback and canker

22 3/26/2018

Kousa dogwood (Cornus kousa) Tomato (Lycopersicon esculentum): rot caused by Late Blight (Lycopersicon esculentum) decline

Signs: evidence of the actual causal agent Diseases: • fungal fruiting bodies • fungal mycelia • bacterial slime (more later…) Insects: • the insect itself • boring holes or tunnels • sawdust • frass… Other… • rodent mounds/holes • slug trails

Goldenchain tree (Laburnum x watereri): aphids Apple ( domestica): Crane fly (Tipula sp.)

Sunflower ( annuus): Sclerotinia wilt (Sclerotinia sclerotiorum) Apple (Malus domestica): Rust (Gymnosporangium sp.)

23 3/26/2018

Incense-cedar (Calocedrus decurrens): Broom rust (Gymnosporangium libocedri) Big-leaf maple (Acer macrophyllum): Tar spots (Rhytisma punctatum)

Cherry (Prunus sp.): possible Bacterial canker damage (Pseudomonas syringae) Apple (Malus domestica): Leaf roller (species undetermined)

Hebe (Hebe sp.): Meadow spittle bugs Rhododendron (Rhododendron sp.): Lace Bug (Stephanitis pyrioides) (Philaenus spumarius)

24 3/26/2018

Viburnum davidii: leaf notching due to root weevils Blue Spruce (Picea pungens): White Pine weevil (Pissodes strobi)

Cherry (Prunus sp.): leafroller activity Slug trails

Some signs cannot be seen without magnification

Vole burrows Red raspberry (Rubus idaeus): RBDV

25 3/26/2018

‘Brooks’ Plum (Prunus domestica): possible Bacterial canker (Pseudomonas syringae)

Websites for home garden problems

Pesticide recommendations for homeowners • Plant Disease Control: • PNW Disease Management Handbook http://pnwhandbooks.org/plantdisease/

• Insect Pest Control: • PNW Insect Management Handbook https://pnwhandbooks.org/insect

• Control: • PNW Weed Management Handbook http://pnwhandbooks.org/weed/

Pear (Pyrus communis): Leaf spot-undetermined cause

Common cultural and environmental problems in Cultural causes of plant problems the garden and how to recognize them

• Planting practices

• Rootbound

• Root damage

• Pruning injury

Neil Bell • Herbicide injury OSU Extension Service Marion and Polk Counties

26 3/26/2018

White-bark birch (Betula jacquemontii)

Root-bound plants

Fig (Ficus carica): circling roots

Deodar cedar (Cedrus deodara)

27 3/26/2018

Western Juniper European White Birch (Betula pendula) (Juniperus occidentalis)

Pruning problems

Deodar cedar (Cedrus deodara)

Rockrose (Cistus x hybridus)

28 3/26/2018

Oriental Arborvitae: Platycladus orientalis

Pesticide injury

Raspberry (Rubus idaeus): glyphosate damage Photo: B. Strik

Bearded (Iris sp.): glyphosate damage

29 3/26/2018

Pine (Pinus sp.) Oak leaf Hydrangea (): phenoxy herbicide damage Phenoxy herbicide damage

Rose (Rosa sp.): acetic acid herbicide injury

Deodar Cedar (Cedrus deodara): phenoxy herbicide damage

Environmental causes of problems

• Cold Injury

• Pollination problems

• Sun (too much or too little)

• Water (too little or too much)

• Nutrient deficiencies

• Wind/hail/lightning Cold Injury

30 3/26/2018

Cold injury results from: Rare to see winter injury to deciduous shrubs and trees or conifers

• Winter low temperatures

• Unexpected frosts

Shrub dogwood (Cornus sericea ‘Kelseyi’) Port Orford Cedar (Chamaecyparis lawsoniana)

Coyote brush (Baccharis pilularis) Mexican (Choisya ternata)

Apple (Malus domestica) Marion trailing blackberry (Rubus ‘Marion’)

31 3/26/2018

Frost damage

English yew (Taxus baccata): snow damage Strawberry (Fragaria x ananassa) Photos: B. Strik

Pollination problems

Honeybee (Apis mellifera) on blueberry (Vaccinium corymbosum) Zucchini ( pepo)

Too much or too little sun

Grape (Vitis sp.) Vine maple (Acer circinatum)

32 3/26/2018

Sunburn can occur on leaves, flowers, fruit or stems… Distinguish between excess sun (sunburn) and drought stress

Sunburn occurs when a plant, or plant part is exposed to too much sun and heat, even if well-supplied with water

Drought stress occurs to any plant when water becomes limiting

Rhododendron: (Rhododendron sp.) Japanese barberry (Berberis thunbergii): yellow-foliaged

Hosta sp.: sunburn

33 3/26/2018

Sunburn on flowers

Flowering dogwood (Cornus ): heat? Mophead Hydrangea (Hydrangea macrophylla)

Sunburn on fruit

Red Maple (Acer rubrum)

Lack of sun can cause problems…

Atlas Cedar (Cedrus atlantica ‘Glauca Pandula’): winter sunburn?

34 3/26/2018

Flowering dogwood: (Cornus canadensis)

Mugo Pine: Flowering dogwood () (Pinus mugo)

Too much or too little water

35 3/26/2018

Symptoms of drought stress Drought stress is dependent on:

• Inherent drought tolerance of plant • Drooping foliage • Tip burn • Weather conditions (temperature, wind) • Brown areas on leaves • Site exposure and aspect • Loss of older leaves • Shoot dieback • Soil conditions (moisture, structure etc.)

• Irrigation (and it’s efficacy)

Hebe sp.

Pacific Dogwood (Cornus nuttalli) Red Alder (Alnus rubra): drought stress

Katsura tree: (Cercidiphyllum japonicum)

36 3/26/2018

Ponderosa Pine Pinus ponderosa Rhododendron (Rhododendron sp.)

Drainage Problems

Douglasfir (Pseudotsuga menziesii)

Drainage problems result from:

• Topography

• Impervious soil

Leyland Cypress: (x Cupresssocyparis leylandii)

37 3/26/2018

Raspberry (Rubus idaeus): Phytophthora root rot (Phytophthora spp.) Boysenberry (Rubus ‘Boysen’)

Nutrient deficiencies in plants

Dicentra spectabilis ‘Gold Heart’

Nutrients required by plants Location of symptoms:

Major nutrients: Minor nutrients: Base of plant – mobile (N, P, K, Mg) Nitrogen (N) Iron (Fe) Phosphorus (P) Zinc (Zn) Potassium (K) Manganese (Mn) Whole (mid) plant – partially mobile (S, Mo) Copper (Cu) Calcium (Ca) Molybdenum (Mo) Magnesium (Mg) Boron (B) Sulfur (S) Chlorine (Cl) Top of plant – immobile (Ca, Fe, Mn, Zn, Cu, B)

Also: salt toxicity….

38 3/26/2018

Mobile nutrient: symptoms at plant base

Flowering plum (Prunus x blireana)

Mobile nutrient: Nitrogen deficiency

Japanese Fatsia (Fatsia japonica ‘Variegata’) Rhododendron (Rhododendron sp.): Nitrogen deficiency

Turf: Nitrogen deficiency

39 3/26/2018

Immobile Nutrient: Iron

Rhododendron (Rhododendron sp.): pH-induced Fe deficiency

Immobile Nutrient deficiency in fruit: Calcium

Blueberry (Vaccinium corymbosum: pH-induced Fe deficiency Apple (Malus domestica): bitter pit

Salt toxicity

Tomato (Lycopersicon esculentum): Blossom end rot Winged Euonymus (Euonymus alatus): salt toxicity

40 3/26/2018

Wind

Hardy Kiwifruit (Actinidia arguta): scarred fruit

Hail

Apple (Malus domestica): Hail damage Highbush blueberry (Vaccinium corymbosum): hail damage

41 3/26/2018

Douglasfir (Pseudotsuga menziesii): Lightning damage

42