Sourwood Tree (Oxydendrum Arboreum): Grow Lily of the Valley Tree

Kim Williamson, Author 8 Billion TreesWritten by Kim Williamson

Forestry, Trees and Tree Planting | March 28, 2024

Person wonders about sourwood tree and how to grow sorrel plant (lily of the valley tree) and how to identify sourwood tree bark, leaves, flowers, and seeds, growing zones, planting tips.

The Sourwood Tree, also known as the sorrel tree, is a native, deciduous, medium-sized tree that boasts year-round interest with beautiful colors in every season.

Sometimes called the Lily of the Valley tree for its small, white flower clusters, the sorrel tree has sour leaves and produces sweet honey.

The Sourwood Tree holds a conservation status of “Least Concern” (LC – 3) on the ICUN Red List, signifying that it faces a lower risk of extinction in the wild.16 This classification reflects the current stability and sustainable population of the Sourwood Tree in its natural habitat.

Though it is short-lived, the Sourwood Tree makes an excellent landscape tree with few pest problems and minimal upkeep.

This complete guide explains identifying and growing Oxydendrum arboreum, the Sourwood Tree.

Best Growing Conditions for Sourwood Trees

Sourwood Trees are not considered high maintenance by any standards, but they are fairly intolerant of some environments, particularly when they are young and not yet established.

Graphics with text and images that shows the best growing conditions for sourwood tree.

Homeowners should pay close attention to the best-growing conditions for Sourwood Trees before planting them around their property.

Sourwood Trees prefer:2,8,18

  • Somewhat acidic soil and will not tolerate high pH or limestone-derived soil.6
  • Moist, well-draining soil and will not tolerate dense, compacted soil.
  • Full or partial sun and will not tolerate full shade. They are at their best in full sun.
  • Temperate climates and will not tolerate winter temperatures below -20 °F for extended periods.
  • Open, rural areas and does not tolerate air pollution or root disturbance.
  • Minimal competition and will not grow beyond a shrub if overshadowed or undernourished.

Sourwood Tree Growing Zone

Before planting an Oxydendrum arboreum specimen, it is important to consider the growing zones for Sourwood Tree; where to grow the tree is just as important as how to grow it. The optimal Sourwood Tree growing zone is USDA Zones 5 – 9 (See USDA Plant Hardiness Zone Map).27

Sourwood Trees are not particularly tolerant of unfavorable conditions and are much more likely to thrive in temperate climates.18

Sourwood Tree Growth Rate

Given its beauty and pollinator value, many homeowners may be attracted to this tree and consider planting it on their property. Before doing so, they may wish to find out how long it takes to grow Sourwood Trees.

Unfortunately, the Sourwood Tree growth rate is relatively slow, particularly for a small to mid-sized tree. Growing around one foot per year, the Sourwood is unlikely to reach maturity until around 30 years of age.

However, the great news about Sourwoods is that they are beautiful as young trees and often bloom as soon as four years after planting.2,17

Growing a Sourwood Tree From a Seed, Cutting, or Seedling

Deciding to grow a tree of a new species for the first time is a big step. It can be particularly daunting if the species is unfamiliar or if the grower has little experience growing trees in general.

A Sourwood Tree might just be that unfamiliar species for many people. This section explores everything gardeners and homeowners should know about growing a Sourwood Tree from a seed, cutting, or seedling.

The first step in growing a Sourwood Tree is choosing the type of tree to plant. Luckily, in the case of Sourwoods, there are few cultivars, with each offering its own appeal.

Look for these cultivars at local nurseries:7,12

  • Albomarginatum: Foliage has white marbling and white margins.
  • Chameleon: Conical in form. Fall colors include red, yellow, and purple.
  • Mt. Charm: Fall colors present early in bright shades. Symmetrical in form.

After selecting the tree, the second step is to choose the location. Remember that while sorrel trees can tolerate partial shade, full sun conditions will enhance their growth and color vibrancy.

An open, sunny location away from competing trees is ideal. When determining how far apart to plant Sourwood Trees, remember to allow enough space for the crown to spread 20 to 30 feet at maturity.

Planting on gentle slopes will promote good drainage.5 The third step to growing a Sourwood Tree is to test the soil.

Sourwoods are partial to slightly acidic, well-draining soil. So, they should not be planted in compacted, clay soil or in soil with a pH higher than 6.5.

Soil can be amended by adding compost, manure, or peat moss.2 Fourthly, it is important to decide when to plant Sourwood Tree for the best yield.

Sourwoods are slow growers, so they won’t bloom for the first few years, but young sorrel trees can be a bit finicky, so timing the planting properly can increase the chances of success. Early spring is the best time to plant Sourwoods.

Growing a Sourwood Tree from a cutting is not recommended, per the USDA, as this propagation method is not consistently successful.8 Sourwood Trees can be grown from seeds, seedlings, or transplants, and propagation from seed is recommended, seed can be started in moist, sandy peat.8,17

When growing from seed, prepare the medium first and scatter the seed lightly along the surface. The seed requires light to germinate, so covering it with a clear lining is advised to retain moisture and heat while not negating light exposure.10

Photo of sourwood tree on a mountain.

(Image: Plant Image Library40)

Growing a Sourwood Tree from a seedling or a transplant is also possible, but it is very important to transplant while the tree is very young. Sorrel trees have fibrous, spreading root systems that are easily damaged, so they must be transplanted before the root system grows too large to remove entirely.

Other planting tips for Sourwood Trees are fairly simple. Keep seedlings well-watered and protected.

Ensure they get plenty of sunlight. Mulch around young trees to retain moisture.

Protect from grazing animals when young.

Sourwood tree, Lily of the Valley tree, Sorrel tree

(Oxydendrum arboreum)

Photo of Sourwood Tree in an oval frame on green background.
  • Characteristics: Sourwood is a deciduous tree native to the Eastern U.S. which bears long, slender, colorful leaves and small white flowers in dangling clusters.
  • Family: Ericaceae
  • Genus: Oxydendrum
  • Type: Deciduous
  • Leaf: Simple, alternating, slightly serrated leaves are glossy and oblong, growing up to 6 inches in length. Fall color is usually crimson.
  • Bark: Bark is thick and dark gray with ridges and scales which become deeply furrowed with age.
  • Seed: Tiny, ⅛ in. seeds contained within a woody capsule.
  • Blossoms: Small, white, bell-shaped flowers bloom in summer in a drooping panicle up to 8 inches in length.
  • Fruit: Small, dry capsules ripen from pale yellow to brown and then to gray in the fall.
  • Height: Generally around 30 ft, but up to 60 ft.
  • Canopy: Up to 20 ft.
  • Lifespan: Approximately 80 years.
  • Native Habitat: Eastern United States
  • Native Growing Zone: USDA zones 5a - 9b

IUCN Red List of Threatened Species Ranking

Least Concern

NE
DD
LC
NT
VU
EN
CR
EW
EX

Image Credit: Agnieszka Kwiecień, Nova41

What Is a Sourwood Tree or Sorrel Tree (Oxydendrum Arboreum)?

The Sourwood Tree is a beautiful, mid-size native tree that flourishes in upland areas with semi-acidic soil. It is so named because of the slightly acidic, sour taste of the leaves which have been used medicinally with some success.

Also called the sorrel tree or Lily of the Valley tree, this tree is commonly seen in the understory of woodland areas along the Southern Appalachian mountain region. However, it actually grows best in full sun conditions where it makes a lovely landscape tree boasting almost year-round color.

The Sourwood, or Oxydendrum arboreum, is the only species in the Oxydendrum genus.22

The following are a few interesting Sourwood Tree facts for curious readers:9,11

  1. The Sourwood Tree was first cultivated in 1747.
  2. The Sourwood Tree is the sole member of the Oxydendrum genus.
  3. The nectar of Sourwood flowers is used by bees to produce rich and delicious honey which is considered a delicacy and can be purchased in some areas of the Eastern United States.
  4. The bark and leaves of the sorrel tree were used medicinally by Native American tribes.
  5. The Lily of the Valley tree is in the blueberry family, Ericaceae.23
  6. Oxydendrum arboreum does not thrive in urban areas with high pollution levels.9
  7. The Sourwood is an excellent wildlife and pollinator tree.
  8. The small woody capsules remain on the tree long after the leaves fall, adding winter interest.

Why Is It Called the Lily of the Valley Tree?

Oxydendrum arboreum is also known as the Lily of the Valley tree due to the blossoms’ resemblance to the flower of the same name: Lily of the Valley (Convallaria majalis).24 Both the Lily of the Valley tree and the herbaceous plant are adorned with small, drooping flowers in a characteristic bell shape.

These tiny white flowers grow in showy, hanging clusters which are quite lovely.17

How To Identify Sourwood Trees (Sorrel Tree Identification)

Individuals may want to know how to identify Sourwood Trees on their property. Luckily, this native tree has some distinguishing characteristics that make it relatively easy to recognize.

Graphic with text and images that shows how to identify sourwood tree through bark, leaves, fruits, flowers, and seeds.

(Bark Image: David J. Stang42, Leaves Image: Krzysztof Ziarnek, Kenraiz43, Fruits Image: David J. Stang44, Flowers Image: Agnieszka Kwiecień, Nova45, and Seeds Image: Famartin46)

From its size to its shape to its growth habit to its various components, the Sourwood Tree is certainly unique! Most sorrel trees reach maturity at an adult size of 30 to 40 feet, though some specimens have been known to reach heights of 60 to 80 feet in ideal environments.

The Sourwood Tree generally has a slender trunk with branches beginning a few feet above the ground. The trunk may appear crooked or twisted if it competes with taller trees for sunlight.

It grows from a broader base which gradually tapers to a rounded crown. The branches trend in a graceful, downward-sweeping fashion.17

Sourwood Trees are native to the Southeastern region of the United States, and they flourish in upland mountainous areas. Commonly seen as an understory tree in forested areas, the Sourwood also makes a great standalone tree with ornamental value.8,18,20

Identifying Sourwood Seeds

Sourwood seeds are minute, about ⅛ inch in size.40 The light brown seeds are oval-shaped and wrapped in a papery coating which forms two wing-like points.

Several seeds are held in a single fruiting body.2 The fruit of the Sourwood Tree are small, woody capsules that turn from pale yellow to gray as they ripen and dry.44

They are 5-compartmented, egg-shaped capsules which are typically less than ½ in long and grow in erect clusters all over the tree. The fruit develops in late summer/early fall and ripens around October.

When ripe, the capsule bursts open, dispersing its seeds but often remaining on the tree well into winter.2

Identifying Sourwood Leaves (Sourwood Leaf Identification)

Sourwood leaves are among the tree’s most distinguishing features.41 They are deciduous, dropping each winter and growing anew each spring.

The leaves are simple and arranged alternately along the length of the twig. Each Sourwood leaf can grow up to 8 inches in length.

The leaves are long and slender, tapering to a point, with a pronounced central vein. The edges of the leaves are usually finely serrated and often slightly wavy.18

In the summer, the leaves develop into a dark, vibrant green with a smooth, glossy texture. The leaves have a sour, acidic taste.

As summer turns to fall, the leaves begin turning to display their vibrant fall colors in hues of yellow, and orange. purple, and crimson red.

The Sourwood Tree often gains its fall color earlier than other local species.2

Identifying Sourwood Tree Bark

Another appreciable sorrel tree feature is its bark.42 Sourwood Tree bark in young trees often appears a deep red hue but may be olive green toned, exhibiting superficial ridges.

As the tree ages, the bark thickens and darkens to a shiny, red-tinged gray, developing deep and long furrows broken intermittently by shorter grooves running horizontally. The ridges of mature trees become scaly and even blocky, similar to the persimmon tree.2,17,18

Identifying Sourwood Flowers

One of the aspects of the tree that makes it so appealing as an ornamental is the flowers.43 Sourwood flowers are quite small and would be somewhat inconspicuous if they grew singly, but they don’t.

The flowers of the Sourwood Tree grow in dense clusters which are quite showy. The individual flowers are a creamy white color and they dangle downward toward the ground on long panicles.

Each flower has four to 5 petals which form a bell shape similar to the Lily of the Valley flower. The flowers appear in early summer and bloom in June.

They emit a gentle pleasant fragrance and produce a rich nectar that appeals to bees and other pollinators. The Sourwood nectar is used by honey bees to produce Sourwood honey, sold locally in the Southern Appalachian region and considered by many to be the most delicious honey.17,20

Sorrel Tree Vs. Sorrel Plants

Sorrel trees should not be confused with other types of sorrel which are herbaceous perennial plants.15 Sorrel plants, also known as ‘dock’ (ex. Narrow-leaved dock [Rumex scutatus]) include around 200 species that are members of the Rumex genus in the Polygonaceae family.25,14,26

Photo of sorrel plant on the ground.

(Image: Sam Beebe47)

Sorrel plants are often weedy, but they are sometimes grown for their edible leaves.14 In fact, the sorrel tree got its name due to the acidic, sour taste of its leaves, resembling that of sorrel plants.17

What Is the Sorrel Tree Pollination Process?

Sorrel trees are monoecious, meaning that individual trees bear both male and female flowers. Tree pollination occurs via insect pollinators, bees in particular, which are drawn to the rich nectar of the copious summer flowers.

The pollinated trees produce small woody fruits which are dry capsules filled with tiny seeds that disperse when the capsules burst.8,19

How Long Does It Take for a Tree To Grow?

Individuals are forever asking “How long does it take for a tree to grow?” Most trees take at least 25 years to reach maturity, but there is so much interspecies variability.

For example, some willow trees can reach maturity in approximately 6 to 8 years, while the coast redwood tree takes at least 500 years and often more than 800 years to grow to its mature size.1,13,21

Watering Needs for Sorrel Trees

Watering a tree is one of the most important aspects of nurturing it, particularly when it is young. While many ornamental trees require regular supplemental watering, the Sourwood Tree really doesn’t.

The watering needs for sorrel trees are very minimal, and mature trees should generally get by with water from rainfall. However, in extreme and prolonged periods of drought, a Sourwood Tree will benefit from water.

Given its shallow root system, it will be less able to draw water from deeper layers of the soil. It is important to note that trees have different watering requirements when they are young.

Particularly in the first two growing seasons after transplanting a small tree, it should be thoroughly watered at least weekly. Mulching around trees when they are young can help them retain moisture and ensure a successful transplant.3

Companion Plants for Growing Sourwood Trees

There are many exemplary companion plants for growing Sourwood Tree. Many are larger types of trees with broad, spreading canopies that allow plenty of sunlight through.

Graphics with texts and images that shows companion plants for growing sourwood tree such as oaks, pines, tulip poplar, sweetgun, hickory, black gum tree, and rosebay.

This is why Sourwood Trees thrive in the upland forest areas of the Eastern U.S., in the understory of tall-growing trees such as oaks (Quercus) and pines (Pinus).28,29 Sourwood is commonly found growing near tulip poplar (Liriodendron tulipifera), sweetgum (Liquidambar styraciflua), and hickory (Carya) trees, all of which have open, not overly dense crowns and non-aggressive lower growth.30,31

This creates a forest canopy that permits much sunlight.2,8 Other companion plants, such as the black gum tree (Nyssa sylvatica), are ideal for the complementary effect of their colors.32

When paired with certain species of Rhododendron and pruned properly, Sourwood Trees can create an attractive natural border.18,33

How Much Sunlight Does Sourwood Tree Need Each Day?

Many people have queried “How much sunlight does Sourwood Tree need each day?” A Sourwood Tree will tolerate significant shade, commonly growing in the understory of trees with taller, broader, and denser canopies.

However, it actually looks its best when it is grown in full sun with minimal competition, bolstering the fullness of the summer blooms and the color of the fall leaves.9,17

Sourwood Tree Disease Prevention (Sorrel Tree Pest Control)

Although many sources state that the Sourwood Tree is not troubled by pests, this is not really accurate, as insect pests can become problematic.2 The most common pests of the Sourwood Tree are the dogwood twig borer (Oberea tripunctata), the azalea stem borer (Oberea myops), and a twig girdler (Oncideres cingulata).34,35,36

Graphics of Sourwood tree pests and diseases showing Dogwood Twig borer, Twig Girdler, Leaf Spot fungi, and Nectria Canker images on green background.

(Twig Girdler Image: Andy Reago & Chrissy McClarren48, Leaf Spot fungi Image: Cwmhiraeth49, and Nectria Canker Image: Sternrenette50)

The best natural pest control for sorrel trees is to ensure they are healthy and vigorous, as weakened trees and those with dead tissue will attract more pests.50,51 In the case where a Sourwood Tree has been impacted by pests, removing any damaged twigs and branches will help the tree rebound quickly.

Sourwood is not known for being prone to disease, but it can be affected by various types of fungi, such as nectria canker (Neonectria ditissima), bot cankers (Botryosphaeria), and leaf spot fungi (Cristulariella).37,38,39 Sourwood Tree disease prevention, similar to pest prevention, involves maintaining a healthy and vigorous tree specimen.47,48,49

Healthy trees should also be kept apart from diseased plants to avoid spreading. Knowing how to stop Sourwood Tree disease may also be helpful down the road.

The best way to stop Sourwood diseases is to prune out any affected branches, removing debris from around the tree. Mature trees can also be fertilized to increase their vigor.4

The Lily of the Valley tree receives its name from the beautiful, small, white, bell-shaped flowers which hang in drooping clusters much like the iconic blossoms of the Lily of the Valley flower.

Aside from its blossoms, Oxydendrum arboreum is also notable for its deeply furrowed bark, its woody seed capsules, and its vibrant fall color.

Knowing how to identify and grow Sourwood Trees (sorrel trees) can enhance your outdoor landscaping.

Read More About Sourwood Tree

References

1Should I Grow a Redwood? UC Davis Arboretum and Public Garden. Retrieved December 6, 2023, from <https://arboretum.ucdavis.edu/sites/g/files/dgvnsk1546/files/inline-files/redwood_exhibits_0.pdf>

2Coder, K. D. (2018, August). Untitled. Warnell School of Forestry and Natural Resources. Retrieved December 7, 2023, from <https://warnell.uga.edu/sites/default/files/inline-files/xSourwood%20Oxydendrum%20arboreum%20pub%202016%20-%20Sourwood%20Oxydendrum%20arboreum%20A%20Honey%20Tree%20ARBOR-24.pdf>

3Engels, L. (2023, May 8). Sourwood Tree (Oxydendrum arboreum): Native Plant Guide. The Spruce. Retrieved December 7, 2023, from <https://www.thespruce.com/sourwood-sorrel-growing-guide-5210869>

4Gilman, E. F., & Watson, D. G. (1994, October). Oxydendrum arboreum Sourwood. Environmental Horticulture. Retrieved December 10, 2023, from <https://hort.ifas.ufl.edu/database/documents/pdf/tree_fact_sheets/oxyarba.pdf>

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7Luken, A., & Schaffner, S. (2023). Plant Profile: Sourwood Tree By Alex Luken & Sarah Schaffner The Sourwood Tree (Oxydendrum arboretum) is native only to Nort. Cave Hill Cemetery. Retrieved December 8, 2023, from <https://www.cavehillcemetery.com/assets/pdfs/news/plant%20profile-%20sourwood%20tree%202020.11-%20final.pdf>

8Overton, R. P. (2023). Oxydendrum arboreum (L. Southern Research Station. Retrieved December 6, 2023, from <https://www.srs.fs.usda.gov/pubs/misc/ag_654/volume_2/oxydendrum/arboreum.htm>

9Oxydendrum arboreum (Lily of the Valley Tree, Sorrel Tree, Sourwood) | North Carolina Extension Gardener Plant Toolbox. (2023). North Carolina Extension Gardener Plant Toolbox. Retrieved December 6, 2023, from <https://plants.ces.ncsu.edu/plants/oxydendrum-arboreum/>

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35Frank, S., & Baker, J. (1994, January 1). Azalea Stem Borer. NC State Extension. Retrieved December 13, 2023, from <https://content.ces.ncsu.edu/azalea-stem-borer-1>

36Oklahoma State University. (2023). TWIG GIRDLER. Oklahoma State University Extension. Retrieved December 13, 2023, from <https://extension.okstate.edu/programs/digital-diagnostics/insects-and-arthropods/twig-girdler-oncideres-cingulata/>

37Blanchette, R. A. (2023). Nectria Canker. University of Minnesota. Retrieved December 13, 2023, from <https://treediseases.cfans.umn.edu/nectriacanker>

38Downer, A. J., & Michailides, T. (2022, July). Botryosphaeria Canker. University of California Agriculture and Natural Resources. Retrieved December 13, 2023, from <https://ipm.ucanr.edu/PMG/PESTNOTES/pn74177.html>

39Leahy, R. M. (1995, March/April). Cristulariella Leaf Spot on Florida Ornamentals. Fla. Dept. Agric. & Consumer Services. Retrieved December 13, 2023, from <https://ccmedia.fdacs.gov/content/download/11377/file/pp370.pdf>

40Oxydendrum arboreum (Sourwood) Photo by Plant Image Library. (2017, November 7) / CC BY-SA 2.0 DEED | Attribution-ShareAlike 2.0 Generic. Cropped and Resized. Flickr. Retrieved December 12, 2023, from <https://flickr.com/photos/138014579@N08/38214211852/>

41Oxydendrum arboreum Kwaśnodrzew amerykański 2019-07-20 01 Photo by Agnieszka Kwiecień, Nova. (2022, June 30) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added text, shape, and background elements. Wikimedia Commons. Retrieved December 11, 2023, from <https://commons.wikimedia.org/wiki/File:Oxydendrum_arboreum_Kwa%C5%9Bnodrzew_ameryka%C5%84ski_2019-07-20_01.jpg>

42Oxydendrum arboreum 15zz Photo by David J. Stang. (2017, July 17) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added image, text, shape, and background elements. Wikimedia Commons. Retrieved December 11, 2023, from <https://commons.wikimedia.org/wiki/File:Oxydendrum_arboreum_15zz.jpg>

43Oxydendrum arboreum kz03 Photo by Krzysztof Ziarnek, Kenraiz. (2020, November 17) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added image, text, shape, and background elements. Wikimedia Commons. Retrieved December 11, 2023, from <https://commons.wikimedia.org/wiki/File:Oxydendrum_arboreum_kz03.jpg>

44Oxydendrum arboreum 12zz Photo by David J. Stang. (2017, July 14) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added image, text, shape, and background elements. Wikimedia Commons. Retrieved December 11, 2023, from <https://commons.wikimedia.org/wiki/File:Oxydendrum_arboreum_12zz.jpg>

45Oxydendrum arboreum Kwaśnodrzew amerykański 2019-07-20 03 Photo by Agnieszka Kwiecień, Nova. (2022, June 30) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added image, text, shape, and background elements. Wikimedia Commons. Retrieved December 11, 2023, from <https://commons.wikimedia.org/wiki/File:Oxydendrum_arboreum_Kwaśnodrzew_amerykański_2019-07-20_03.jpg>

462023-11-13 14 27 11 Sourwood leaves in autumn along Seven Oaks Lane at Twining Lane in the Mountainview section of Ewing Township, Mercer County, New Jersey Photo by Famartin. (2023, November 13) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added image, text, shape, and background elements. Wikimedia Commons. Retrieved December 11, 2023, from <https://commons.wikimedia.org/wiki/File:2023-11-13_14_27_11_Sourwood_leaves_in_autumn_along_Seven_Oaks_Lane_at_Twining_Lane_in_the_Mountainview_section_of_Ewing_Township,_Mercer_County,_New_Jersey.jpg>

47Sorrel Photo by Sam Beebe. (2014, April 22) / CC BY 2.0 DEED | Attribution 2.0 Generic. Cropped and Resized. Flickr. Retrieved December 12, 2023, from <https://flickr.com/photos/sbeebe/13975255494/>

48Twig Girdler Beetle (Oncideres cingulata) Photo by Andy Reago & Chrissy McClarren. (2022, September 30) / CC BY 2.0 DEED | Attribution 2.0 Generic. Cropped and added text and background elements. Flickr. Retrieved January 18, 2024, from <https://www.flickr.com/photos/wildreturn/52395349626/>

49Cristulariella depraedans 1 Photo by Cwmhiraeth. (2016, August 4) / CC BY-SA 4.0 DEED | Attribution-ShareAlike 4.0 International. Cropped and added text and background elements. Wikimedia Commons. Retrieved January 18, 2024, from <https://commons.wikimedia.org/wiki/File:Cristulariella_depraedans_1.jpg>

50Neonectria ditissima – Wucherungen Photo by Sternrenette. (2016, March 28) / CC BY 3.0 DEED Attribution 3.0 Unported. Cropped and added text and background elements. Wikimedia Commons. Retrieved January 18, 2024, from <https://commons.wikimedia.org/wiki/File:Neonectria_ditissima_-_Wucherungen.jpg>