Difference between revisions of "Flowering Dogwood"

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{{Taxobox
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{{SPlantbox
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| color = lightgreen
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|familia=Cornaceae
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| name = Flowering Dogwood
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|genus=Cornus
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| image = Benthamidia florida berry.jpg
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|species=florida
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| image_width = 240px
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|Temp Metric=°F
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| image_caption = Flowering Dogwood in fall with fruit
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|image=Benthamidia florida berry.jpg
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| regnum = [[Plant]]ae
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|image_width=240
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| divisio = [[Flowering plant|Magnoliophyta]]
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|image_caption=Flowering Dogwood in fall with fruit
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| classis = [[Dicotyledon|Magnoliopsida]]
 
−
| ordo = [[Cornales]]
 
−
| familia = [[Cornaceae]]
 
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| genus = ''[[Dogwood|Cornus]]''
 
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| subgenus = ''Benthamidia''
 
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| species = '''''C. florida'''''
 
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| binomial = ''Cornus florida''
 
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| binomial_authority = [[Carolus Linnaeus|L.]]
 
 
}}
 
}}
 +
'''''Cornus florida''''' ('''Flowering Dogwood''', [[synonymy|syn.]] ''Benthamidia florida'' (L.) Spach) is a species of [[dogwood]] native to eastern [[North America]], from southern [[Maine]] west to southern [[Ontario]] and eastern [[Kansas]], and south to northern [[Florida]] and eastern [[Texas]] and also in [[Illinois]], with a disjunct population in eastern [[Mexico]] in [[Nuevo León]] and [[Veracruz]].
  
−
The '''Flowering Dogwood''', '''American Dogwood''', '''Cornelian Tree''', '''False Box''', '''False Boxwood''', '''Florida Dogwood''', '''Indian Arrowwood''', '''Nature's Mistake''' or, '''White Cornel''' (''Cornus florida'', [[synonymy|syn.]] ''Benthamidia florida'') is a species of [[dogwood]] native to eastern [[North America]], from southern [[Maine]] west to southern [[Ontario]] and eastern [[Kansas]], and south to northern [[Florida]] and eastern [[Texas]], with a disjunct population in eastern [[Mexico]] in [[Nuevo León]] and [[Veracruz]].
+
Flowering dogwood is a small [[deciduous]] [[tree]] growing to {{convert|10|m|ft|abbr=on}} high, often wider than it is tall when mature, with a trunk diameter of up to {{convert|30|cm|ft|0|abbr=on}}. A 10-year-old tree will stand about {{convert|5|m|ft|0|abbr=on}} tall. The [[leaf|leaves]] are opposite, simple, ovate, 6–13 cm long and 4–6 cm broad, with an apparently entire margin (actually very finely toothed, under a lens); they turn a rich red-brown in fall.  
  
−
[[Image:White dogwood flower.jpg|left|thumb|A single flowerhead, showing the large white petal-like bracts and the tight cluster of small greenish-yellow flowers. Early May, [[Pittsburgh, Pennsylvania]]]]
+
The [[flower]]s are individually small and inconspicuous, with four greenish-yellow petals 4 mm long. Around 20 flowers are produced in a dense, rounded, [[umbel]]-shaped [[inflorescence]], or flower-head, 1–2 cm in diameter. The flower-head is surrounded by four conspicuous large white, pink or red "petals" (actually [[bract]]s), each bract 3 cm long and 2.5 cm broad, rounded, and often with a distinct notch at the apex. The flowers are bisexual.
−
It is a small [[deciduous]] [[tree]] growing to 10 m high, with a trunk diameter of up to 30 cm. The [[leaf|leaves]] are opposite, simple acute oval, 6-13 cm long and 4-6 cm broad, with an apparently entire margin (actually very finely toothed, under a lens); they turn a rich red-brown in fall.  
 
  
−
The [[flower]]s are individually small and inconspicuous, with four greenish-yellow petals 4 mm long. Around 20 flowers are produced in a dense, rounded, [[inflorescence|flowerhead]] 1-2 cm diameter, the flowerhead surrounded by four conspicuous large white or pink "petals" (actually [[bract]]s), each bract 3 cm long and 2.5 cm broad, rounded, and with a distinct notch at the apex. The flowers are [[plant sexuality|bisexual]].  
+
While most of the wild trees have white bracts, some selected [[cultivar]]s of this tree also have pink bracts, some even almost a true red. They typically flower in early April in the southern part of their range, to late April or early May in northern and high altitude areas. The similar [[Kousa Dogwood]] (''Cornus kousa''), native to [[Asia]], flowers about a month later.
 +
 
 +
The [[fruit]] is a cluster of two to ten [[drupe]]s, each 10–15 mm long and about 8 mm wide, which ripen in the late summer and the early fall to a bright red, or occasionally yellow with a rosy blush. They are an important food source for dozens of species of [[bird]]s, which then distribute the [[seed]]s.
 +
 
 +
{{Inc|
 +
Cornus florida, Linn. (Cynoxylon floridum, Raf.). Flowering Dogwood. Shrub or small tree with spreading branches, 10-15 ft., rarely to 40 ft.: lvs. oval or ovate, acute, dark green and glabrous above, glaucous or whitish beneath, usually only pubescent on the veins, 3-6 in. long: involucre white or pinkish, 3—4 in. wide; bracts 4, obovate, emarginate: fr. ½in. long, scarlet. May. Mass, to Fla., west to Ont. and Texas, also E. and S. Mex.—One of the most beautiful American flowering trees; hardy N. Var. pendula, Dipp. With pendulous branches. Var. rubra, Andr6. With pink involucre. Neither variety as hardy as the type.
 +
}}
 +
 
 +
[[File:Dogwood flower closeup 20080427 141400 1 crop sharp.png|right|thumb|Close up of a flower cluster showing the four yellow petals on each flower.]]
 +
Flowering Dogwood does best [[horticulture|horticulturally]] in moist, acidic soil in a site with some afternoon [[shade]], but good morning sun. It does not do well when exposed to intense heat sources such as adjacent parking lots or [[air conditioning]] [[Gas compressor|compressors]]. It also has a low [[Soil salinity|salinity]] tolerance. In urban and suburban settings, care should be taken not to inflict mower damage on the trunk or roots, as this increases the tree’s susceptibility to disease and pest pressure.<ref>Cappiello, P and D Shadow. 2005. Dogwoods: The Genus Cornus. Timber Press, Portland. pp 98-100.</ref>
 +
 
 +
In regions where dogwood [[anthracnose]] is a problem, homeowners and public land managers are encouraged to know the symptoms and inspect trees frequently. The selection of healthy, disease-free planting stock is essential and transplanting trees from the forest should be avoided. Sites should be selected for reasonably well-drained, fertile soils; full sun is recommended in high-hazard areas (such as stream or pond banks). New plantings should be mulched to a depth of {{convert|2|to|4|in|cm|0|abbr=off}}, avoiding the stem. Dead wood and leaves should be pruned and completely removed and destroyed yearly. Plants should be watered weekly during droughts, with watering done in the morning, avoiding wetting the foliage. Registered fungicides can be applied when necessary, according to manufacturers instructions and advice of local Extension Service.<ref>Anderson, RL, JL Knighten, M Windham, K Langdon, F Hendrix, R Roncadori. 1994. Dogwood anthracnose and its spread in the South. Project Report R8-PR 26. USDA Forest Service, Atlanta, GA. 10pp.</ref> 
 +
 
 +
Flowering dogwood is grown widely throughout mid-temperate North America. In the eastern part of the continent, it is cultivated as far north as [[Toronto, Ontario|Toronto]] and south to central [[Florida]]. Farther west, places of cultivation include [[Boulder, Colorado|Boulder]], [[Sacramento, California|Sacramento]] and [[Vancouver, Canada|Vancouver]]. It is also sold in other temperate parts of the world, including [[Sydney]], [[Australia]].
 +
 
 +
==Cultivation==
 +
 
 +
 
 +
===Propagation===
 +
''Cornus florida'' is easily propagated by seeds, which are sown in the fall into prepared rows of sawdust or sand, and emerge in the spring. Germination rates for good clean seed should be near 100% if seed dormancy is first overcome by cold stratification treatments for 90 to 120 days at {{convert|4|°C|°F|abbr=on}}.<ref>Cappiello, P and D Shadow. 2005. Dogwoods: The Genus Cornus. Timber Press, Portland. pp 100-102.</ref><ref name="Hartmann, HT 2002. pp. 769">Hartmann, HT, DE Kester, FT Davies, RL Geneve. 2002. Hartmann and Kester’s Plant Propagation: Principles and Practices, 7th Edition. Prentice Hall, Upper Saddle River, NJ. pp. 769.</ref>
 +
 
 +
Flowering dogwood demonstrates gametophytic self-incompatibility, meaning that the plants can’t self-fertilize. This is important for breeding programs as it means that it is not necessary to emasculate (remove the anthers from) ''C. florida'' flowers before making controlled cross-pollinations. These pollinations should be repeated every other day, as the flowers must be cross-pollinated within one or two days of opening for pollinations to be effective.<ref>Reed, SM. 2004. Self-incompatibility in ''Cornus florida''. HortScience 39(2): 335-338.</ref>
 +
 
 +
Softwood cuttings taken in late spring or early summer from new growth can be rooted under mist if treated with 8,000 to 10,000 ppm [[indole-3-butyric acid]] (IBA). In cold climates, potted cuttings must be kept in heated cold frames or [[polyhouse]]s the following winter to maintain temperatures between 0 and 7°C. Although rooting success can be as high as 50-85%, this technique is not commonly used by commercial growers. Rather, selected cultivars are generally propagated by [[Shield budding|T-budding]] in late summer or by whip [[grafting]] in the greenhouse in winter onto seedling rootstock.<ref name="Hartmann, HT 2002. pp. 769"/><ref>Cappiello, P and D Shadow. 2005. Dogwoods: The Genus Cornus. Timber Press, Portland. pp 102.</ref>
 +
 
 +
[[Micropropagation]] of flowering dogwood is now used in breeding programs aiming to incorporate resistance to dogwood anthracnose and powdery mildew into horticulturally and economically important cultivars. Nodal ([[axillary bud]]) sections are established in a culture of Woody Plant Medium (WPM) amended with 4.4 μM 6-Benzyladenine (BA) to promote shoot growth.<ref>Kaveriappa, KM, LM Phillips, RN Trigiano. 1997. Micropropagation of flowering dogwood (''Cornus florida'') from seedlings. Plant Cell Reports 16: 485-489.</ref>  Rooting of up to 83% can be obtained when 5-7 week-old microshoots are then transferred to WPM amended with 4.9 μM IBA.<ref>Sharma, AR, RN Trigiano, WT Witte, OJ Schwarz. 2005. In vitro adventitious rooting of ''Cornus florida'' microshoots. Scientia Horticulturae 103: 381-385.</ref>
  
−
While most of the wild trees have white bracts, some selected [[cultivar]]s of this tree also have pink bracts, some even almost a true red. They typically flower in early April in the southern part of their range, to late April or early May in northern and high altitude areas. The similar [[Kousa Dogwood]] (''Cornus kousa''), native to [[Asia]], flowers about a month later.
+
===Pests and diseases===
  
−
The [[fruit]] is a cluster of three to eight 10-15 mm diameter [[drupe]]s which ripen to a bright red in the fall; they are eaten by [[bird]]s which distribute the [[seed]]s. The berries are edible, though lacking in any interesting flavor. <br clear = left>
 
  
 +
==Varieties==
 
There are two [[subspecies]]:
 
There are two [[subspecies]]:
 
*''Cornus florida'' subsp. ''florida''. Eastern [[United States]], southeastern [[Canada]] ([[Ontario]]).
 
*''Cornus florida'' subsp. ''florida''. Eastern [[United States]], southeastern [[Canada]] ([[Ontario]]).
−
*''Cornus florida'' subsp. ''urbiniana'' (syn. ''Cornus urbiniana''). Eastern [[Mexico]] ([[Nuevo León]], [[Veracruz]]).
+
*''Cornus florida'' subsp. ''urbiniana'' (Rose) Rickett (syn. ''Cornus urbiniana'' Rose). Eastern [[Mexico]] ([[Nuevo León]], [[Veracruz]]).
−
 
 
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===Cultivation and uses===
 
−
[[Image:Flowering Dogwood Cornus florida Trunk Bark 3100px.jpg|right|thumb|The bark on the tree's trunk]]
 
−
Growing Dogwood does best [[horticulture|horticulturally]] when it has [[shade]] from the west but has good [[morning]] [[sun]]. It does not do well when exposed to intense [[heat]] sources such as adjacent [[parking lot]]s or [[air conditioning]] [[Gas compressor|compressors]]. It has a low tolerance of [[salt]]. In eastern North America, it is cultivated as far north as [[Toronto, Ontario|Toronto]] and south to central [[Florida]]. Farther west, places of cultivation include [[Boulder, Colorado|Boulder]], [[Sacramento, California|Sacramento]] and [[Vancouver, Canada|Vancouver]]. It is sold in other temperate parts of the world, including [[Sydney]], [[Australia]].
 
−
 
 
−
It is very susceptible to dogwood [[anthracnose]], a [[disease]] caused by the fungus ''Discula destructiva''. This has killed many wild stocks of Flowering Dogwood; domestic [[landscape]] [[plant]]ings have often been affected to a lesser degree because better [[atmospheric circulation|air circulation]] and less [[humid]] conditions discourages the fungus, but losses still occur fre
 
−
quently. The Kousa Dogwood is resistant to this disease.
 
  
 
;Selected cultivars
 
;Selected cultivars
 +
*‘Amerika Touch-O-Pink’ – large bracts, tinged pink; large leaves; good disease resistance.
 +
*‘Appalachian Spring’ – large white bracts; red fall foliage; resistant to dogwood anthracnose.
 
*'Autumn Gold' - white bracts; yellow fall color.
 
*'Autumn Gold' - white bracts; yellow fall color.
−
*'Barton' - large white bracts; blooms at early age; resists mildew.
+
*'Barton' - large white bracts; blooms at early age; resistant to stem canker and powdery mildew.
 
*'Bay Beauty' - double white bracts; resists heat and drought; good for Deep South.
 
*'Bay Beauty' - double white bracts; resists heat and drought; good for Deep South.
 
*'Cherokee Daybreak' - white bract; vigorous grower with variegated leaves.
 
*'Cherokee Daybreak' - white bract; vigorous grower with variegated leaves.
 
*'Cherokee Chief' - red bracts; red new growth.
 
*'Cherokee Chief' - red bracts; red new growth.
 +
*'Cherokee Brave' - Even redder than 'Cherokee Chief', smaller bracts but dark red color; consistently resistant to powdery mildew.
 +
*'Cherokee Princess' - vigorous white bracts, industry standard for white flowers.
 
*'Cherokee Sunset' - purplish-red bracts; variegated foliage.
 
*'Cherokee Sunset' - purplish-red bracts; variegated foliage.
−
*'Gulf Coast Pink' - best pink flowering dogwood in Florida.
+
*'Gulf Coast Pink' - best pink flowering dogwood in Florida &ndash; northern part only.
 
*'Hohman's Gold' - white bracts; variegated foliage.
 
*'Hohman's Gold' - white bracts; variegated foliage.
−
*'Plena' - double white bracts; anthracnose-resistant.
+
*‘Jean’s Appalachian Snow’ – large, overlapping white bracts w/ green flowers; very resistant to powdery mildew.
−
*'Purple Glory' - red bracts; purple foliage; anthracnose-resistant.
+
*‘Karen’s Appalachian Blush’ – delicate white bracts edged in pink; some powdery mildew resistance.
 +
*‘Kay’s Appalachian Mist’ – stiff, creamy white bracts; red fall foliage; good resistance to powdery mildew.
 +
*'Plena' - double white bracts; spot anthracnose-resistant.
 +
*'Purple Glory' - red bracts; purple foliage; spot anthracnose-resistant but susceptible to stem canker.
 
*'Weaver White' - large white blooms; large leaves; candelabra shape; good in north-central Florida.
 
*'Weaver White' - large white blooms; large leaves; candelabra shape; good in north-central Florida.
  
−
==References and external links==
+
==Gallery==
−
*[http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?11551 Germplasm Resources Information Network: ''Cornus florida'']
+
<gallery perrow=5>
−
*[http://plants.usda.gov/java/profile?symbol=COFL2 NRCS: USDA Plants Profile: ''Cornus florida'']
+
File:Missouri state capitol with flowering dogwood.jpg| A Flowering Dogwood with the Missouri State Capitol in the background
−
*[http://www.missouriplants.com/Others/Cornus_florida_page.html Missouriplants: ''Cornus florida'']
+
File:floweringdogwood2.jpg|A Flowering Dogwood cultivar with pink flowers
−
*[http://www.cas.vanderbilt.edu/bioimages/species/frame/cofl2.htm Bioimages: ''Cornus florida'']
+
File:floweringdogwood.jpg|A Flowering Dogwood cultivar with white flowers
−
 
+
File:Benthamidia florida autumn.jpg|Tree shape, autumn
−
<gallery>
+
File:Flowering Dogwood Cornus florida 'Appalacian Spring' Sapling 2000px.JPG|Sapling of ''C. florida'' 'Appalacian Spring'
−
Image:floweringdogwood2.jpg|A Flowering Dogwood cultivar with pink flowers
+
File:Flowering Dogwood Cornus florida 'Appalacian Spring' Leaves 3000px.JPG|Leaves of ''C. florida'' 'Appalacian Spring'
−
Image:floweringdogwood.jpg|A Flowering Dogwood cultivar with white flowers
+
File:Flowering Dogwood Cornus florida 'Appalacian Spring' Leaf 2650px.JPG|Leaf closeup of ''C. florida'' 'Appalacian Spring'
−
Image:Benthamidia florida autumn.jpg|Tree shape, autumn
+
File:dogwood_fall_20080928_120751_1.jpg| Leaves of ''C. florida'' in the autumn
−
Image:Flowering Dogwood Cornus florida 'Appalacian Spring' Sapling 2000px.JPG|Sapling of ''Cornus florida'' 'Appalacian Spring'
+
File:P1020222.JPG|A pink-flowered ''C. florida''.
−
Image:Flowering Dogwood Cornus florida 'Appalacian Spring' Leaves 3000px.JPG|Leaves of ''Cornus florida'' 'Appalacian Spring'
+
File:BayBeauty.JPG|White ''C. florida''.  'Bay Beauty'. Note the double bracts.
−
Image:Flowering Dogwood Cornus florida 'Appalacian Spring' Leaf 2650px.JPG|Leaf closeup of ''Cornus florida'' 'Appalacian Spring'
+
File:CornusFlorida.jpg|Closeup of bark
 
</gallery>
 
</gallery>
  
−
[[Category:Cornales|Dogwood, Flowering]]
+
==References==
 +
<references/>
 +
<!--- xxxxx  *Flora: The Gardener's Bible, by Sean Hogan. Global Book Publishing, 2003. ISBN 0881925381  -->
 +
<!--- xxxxx  *American Horticultural Society: A-Z Encyclopedia of Garden Plants, by Christopher Brickell, Judith D. Zuk. 1996. ISBN 0789419432  -->
 +
<!--- xxxxx  *Sunset National Garden Book. Sunset Books, Inc., 1997. ISBN 0376038608  -->
  
−
[[Category:Trees of Southeastern Canada|Dogwood, Flowering]]
+
==External links==
−
[[Category:Trees of Eastern United States|Dogwood, Flowering]]
+
*{{wplink}}
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[[Category:Trees of Southeastern United States|Dogwood, Flowering]]
 
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[[Category:Trees of Plains-Midwest U.S.|Dogwood, Flowering]]
 
−
[[Category:Trees of Florida|Dogwood, Flowering]] <!-- as opposed to just continental N. Florida, I assume it is towards the south of the state -->
 
  
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[[Category:Trees of Mexico|Dogwood, Flowering]]
+
{{stub}}
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[[Category:Trees of Nuevo León|Dogwood, Flowering]]
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__NOTOC__
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[[Category:Trees of Veracruz|Dogwood, Flowering]]
 
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[[Category:Medicinal plants]]
 
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[[Category:Symbols of Virginia]]
 

Revision as of 04:30, 8 May 2011


Flowering Dogwood in fall with fruit


Plant Characteristics
Cultivation
Scientific Names

Cornaceae >

Cornus >

florida >


Cornus florida (Flowering Dogwood, syn. Benthamidia florida (L.) Spach) is a species of dogwood native to eastern North America, from southern Maine west to southern Ontario and eastern Kansas, and south to northern Florida and eastern Texas and also in Illinois, with a disjunct population in eastern Mexico in Nuevo León and Veracruz.

Flowering dogwood is a small deciduous tree growing to 10 m ft high, often wider than it is tall when mature, with a trunk diameter of up to 30 cm ft 0. A 10-year-old tree will stand about 5 m ft 0 tall. The leaves are opposite, simple, ovate, 6–13 cm long and 4–6 cm broad, with an apparently entire margin (actually very finely toothed, under a lens); they turn a rich red-brown in fall.

The flowers are individually small and inconspicuous, with four greenish-yellow petals 4 mm long. Around 20 flowers are produced in a dense, rounded, umbel-shaped inflorescence, or flower-head, 1–2 cm in diameter. The flower-head is surrounded by four conspicuous large white, pink or red "petals" (actually bracts), each bract 3 cm long and 2.5 cm broad, rounded, and often with a distinct notch at the apex. The flowers are bisexual.

While most of the wild trees have white bracts, some selected cultivars of this tree also have pink bracts, some even almost a true red. They typically flower in early April in the southern part of their range, to late April or early May in northern and high altitude areas. The similar Kousa Dogwood (Cornus kousa), native to Asia, flowers about a month later.

The fruit is a cluster of two to ten drupes, each 10–15 mm long and about 8 mm wide, which ripen in the late summer and the early fall to a bright red, or occasionally yellow with a rosy blush. They are an important food source for dozens of species of birds, which then distribute the seeds.


Read about Flowering Dogwood in the Standard Cyclopedia of Horticulture 

Cornus florida, Linn. (Cynoxylon floridum, Raf.). Flowering Dogwood. Shrub or small tree with spreading branches, 10-15 ft., rarely to 40 ft.: lvs. oval or ovate, acute, dark green and glabrous above, glaucous or whitish beneath, usually only pubescent on the veins, 3-6 in. long: involucre white or pinkish, 3—4 in. wide; bracts 4, obovate, emarginate: fr. ½in. long, scarlet. May. Mass, to Fla., west to Ont. and Texas, also E. and S. Mex.—One of the most beautiful American flowering trees; hardy N. Var. pendula, Dipp. With pendulous branches. Var. rubra, Andr6. With pink involucre. Neither variety as hardy as the type.


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Close up of a flower cluster showing the four yellow petals on each flower.

Flowering Dogwood does best horticulturally in moist, acidic soil in a site with some afternoon shade, but good morning sun. It does not do well when exposed to intense heat sources such as adjacent parking lots or air conditioning compressors. It also has a low salinity tolerance. In urban and suburban settings, care should be taken not to inflict mower damage on the trunk or roots, as this increases the tree’s susceptibility to disease and pest pressure.[1]

In regions where dogwood anthracnose is a problem, homeowners and public land managers are encouraged to know the symptoms and inspect trees frequently. The selection of healthy, disease-free planting stock is essential and transplanting trees from the forest should be avoided. Sites should be selected for reasonably well-drained, fertile soils; full sun is recommended in high-hazard areas (such as stream or pond banks). New plantings should be mulched to a depth of 2 to 4 in, avoiding the stem. Dead wood and leaves should be pruned and completely removed and destroyed yearly. Plants should be watered weekly during droughts, with watering done in the morning, avoiding wetting the foliage. Registered fungicides can be applied when necessary, according to manufacturers instructions and advice of local Extension Service.[2]

Flowering dogwood is grown widely throughout mid-temperate North America. In the eastern part of the continent, it is cultivated as far north as Toronto and south to central Florida. Farther west, places of cultivation include Boulder, Sacramento and Vancouver. It is also sold in other temperate parts of the world, including Sydney, Australia.

Cultivation

Propagation

Cornus florida is easily propagated by seeds, which are sown in the fall into prepared rows of sawdust or sand, and emerge in the spring. Germination rates for good clean seed should be near 100% if seed dormancy is first overcome by cold stratification treatments for 90 to 120 days at 4 °C °F .[3][4]

Flowering dogwood demonstrates gametophytic self-incompatibility, meaning that the plants can’t self-fertilize. This is important for breeding programs as it means that it is not necessary to emasculate (remove the anthers from) C. florida flowers before making controlled cross-pollinations. These pollinations should be repeated every other day, as the flowers must be cross-pollinated within one or two days of opening for pollinations to be effective.[5]

Softwood cuttings taken in late spring or early summer from new growth can be rooted under mist if treated with 8,000 to 10,000 ppm indole-3-butyric acid (IBA). In cold climates, potted cuttings must be kept in heated cold frames or polyhouses the following winter to maintain temperatures between 0 and 7°C. Although rooting success can be as high as 50-85%, this technique is not commonly used by commercial growers. Rather, selected cultivars are generally propagated by T-budding in late summer or by whip grafting in the greenhouse in winter onto seedling rootstock.[4][6]

Micropropagation of flowering dogwood is now used in breeding programs aiming to incorporate resistance to dogwood anthracnose and powdery mildew into horticulturally and economically important cultivars. Nodal (axillary bud) sections are established in a culture of Woody Plant Medium (WPM) amended with 4.4 μM 6-Benzyladenine (BA) to promote shoot growth.[7] Rooting of up to 83% can be obtained when 5-7 week-old microshoots are then transferred to WPM amended with 4.9 μM IBA.[8]

Pests and diseases

Varieties

There are two subspecies:

Selected cultivars
  • ‘Amerika Touch-O-Pink’ – large bracts, tinged pink; large leaves; good disease resistance.
  • ‘Appalachian Spring’ – large white bracts; red fall foliage; resistant to dogwood anthracnose.
  • 'Autumn Gold' - white bracts; yellow fall color.
  • 'Barton' - large white bracts; blooms at early age; resistant to stem canker and powdery mildew.
  • 'Bay Beauty' - double white bracts; resists heat and drought; good for Deep South.
  • 'Cherokee Daybreak' - white bract; vigorous grower with variegated leaves.
  • 'Cherokee Chief' - red bracts; red new growth.
  • 'Cherokee Brave' - Even redder than 'Cherokee Chief', smaller bracts but dark red color; consistently resistant to powdery mildew.
  • 'Cherokee Princess' - vigorous white bracts, industry standard for white flowers.
  • 'Cherokee Sunset' - purplish-red bracts; variegated foliage.
  • 'Gulf Coast Pink' - best pink flowering dogwood in Florida – northern part only.
  • 'Hohman's Gold' - white bracts; variegated foliage.
  • ‘Jean’s Appalachian Snow’ – large, overlapping white bracts w/ green flowers; very resistant to powdery mildew.
  • ‘Karen’s Appalachian Blush’ – delicate white bracts edged in pink; some powdery mildew resistance.
  • ‘Kay’s Appalachian Mist’ – stiff, creamy white bracts; red fall foliage; good resistance to powdery mildew.
  • 'Plena' - double white bracts; spot anthracnose-resistant.
  • 'Purple Glory' - red bracts; purple foliage; spot anthracnose-resistant but susceptible to stem canker.
  • 'Weaver White' - large white blooms; large leaves; candelabra shape; good in north-central Florida.

Gallery

  • A Flowering Dogwood with the Missouri State Capitol in the background

  • A Flowering Dogwood cultivar with pink flowers

  • A Flowering Dogwood cultivar with white flowers

  • Tree shape, autumn

  • Sapling of C. florida 'Appalacian Spring'

  • Leaves of C. florida 'Appalacian Spring'

  • Leaf closeup of C. florida 'Appalacian Spring'

  • Leaves of C. florida in the autumn

  • P1020222.JPG

    A pink-flowered C. florida.

  • White C. florida. 'Bay Beauty'. Note the double bracts.

  • Closeup of bark

References

  1. ↑ Cappiello, P and D Shadow. 2005. Dogwoods: The Genus Cornus. Timber Press, Portland. pp 98-100.
  2. ↑ Anderson, RL, JL Knighten, M Windham, K Langdon, F Hendrix, R Roncadori. 1994. Dogwood anthracnose and its spread in the South. Project Report R8-PR 26. USDA Forest Service, Atlanta, GA. 10pp.
  3. ↑ Cappiello, P and D Shadow. 2005. Dogwoods: The Genus Cornus. Timber Press, Portland. pp 100-102.
  4. ↑ 4.0 4.1 Hartmann, HT, DE Kester, FT Davies, RL Geneve. 2002. Hartmann and Kester’s Plant Propagation: Principles and Practices, 7th Edition. Prentice Hall, Upper Saddle River, NJ. pp. 769.
  5. ↑ Reed, SM. 2004. Self-incompatibility in Cornus florida. HortScience 39(2): 335-338.
  6. ↑ Cappiello, P and D Shadow. 2005. Dogwoods: The Genus Cornus. Timber Press, Portland. pp 102.
  7. ↑ Kaveriappa, KM, LM Phillips, RN Trigiano. 1997. Micropropagation of flowering dogwood (Cornus florida) from seedlings. Plant Cell Reports 16: 485-489.
  8. ↑ Sharma, AR, RN Trigiano, WT Witte, OJ Schwarz. 2005. In vitro adventitious rooting of Cornus florida microshoots. Scientia Horticulturae 103: 381-385.

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