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Tales from the Elder: Adulteration Issues of Elder Berry

A review of analytical laboratory evidence documenting adulteration and fraud in the international market for elder berry ingredients

By Stefan Gafner, PhDa; Travis Borchardtb; Melanie Bushc; Sidney Sudbergd; Nicolas G. Feuillère, PhDe; Mathieu Y.R. Tenone; Justine H. Joliboise; Pascale J.N. Bellengere; Hong You, PhDf; Rebecca E. Adamsg; Jeremy Stewart, PhDh; Ido Daganh; Timothy Murray, PhDh; and David L. Erickson, PhDi

a American Botanical Council (Austin, TX)
b Nature's Way Brands (Green Bay, WI)
c Artemis International (Fort Wayne, IN)
d Alkemist Labs (Garden Grove, CA)
e Naturex (Avignon, France)
f Eurofins (Brea, CA)
g Gaia Herbs (Brevard, NC)
h NSF International (Ann Arbor, MI)
i DNA4 Technologies (Baltimore, MD) and University of Maryland (College Park, MD)

 

Botany and Taxonomy

Sambucus nigraThe European elder* (Sambucus nigra L., syn. S. nigra subsp. nigra L., Viburnaceae) is a shallow-rooted tree which can grow up to 10 m (32.8 feet) in height and yields small, round fruit (6-8 mm in diameter) that are dark purple to violet when ripe. The species is distributed throughout most of Europe, from southern Scandinavia to northern Spain, Italy, and Turkey, and east to the Caucasus Mountains.1 It has been introduced to North and South America, and Oceania. The native range of a closely related and morphologically similar species, American elder (Sambucus canadensis L., syn. S. nigra subsp. canadensis (L.) R. Bolli), extends from Nova Scotia and Quebec down through Florida, the West Indies, and Central America, and west from Manitoba to montane Mexico.2,3 Other medicinally used elder species include the southern elder (S. australis Cham & Schldtl.), blue elder (S. cerulea Raf.), dwarf elder (S. ebulus L.), Chinese elder (S. javanica subsp. chinensis (Lindl.) Fukuoka, syn. S. chinensis Lindl.), and Williams elder (S. williamsii Hance).4

The taxonomy of the main elder species in trade is a matter of debate. The five taxonomic databases5-9 consulted for this article consider S. cerulea, S. nigra, and S. canadensis to be separate species, placing them alternatively into the family Viburnaceae5,8,9 or Adoxaceae.6,7 (The US National Plant Germplasm System also lists S. nigra subsp. nigra as a separate species.) This is despite the most recent taxonomic evaluation of the genus by Bolli (1994),10 who proposed classifying five formerly separate taxa (including S. canadensis and S. cerulea) as subspecies of Sambucus nigra. Bolli also argued for the placement of the genus in a separate family — Sambucaceae. A review of Bolli’s work by Applequist11 in 2015 supports the subspecies level of S. nigra subsp. canadensis, but not that of S. cerulea, since the latter is more easily distinguished from S. nigra based on its morphological characteristics.

Applequist also argued that genus Sambucus should be placed in the family Adoxaceae.11 However, several publications from 2020 and 2021 place Sambucus in Viburnaceae,5,8,9 while most older publications prior to 2015 place it within the Caprifoliaceae.4,12,13

Weakley (2020) places Sambucus in the Viburnaceae or viburnum family (rather than the now obsolete Adoxaceae). It was also formerly placed in the Caprifoliaceae (pink family), or in some treatments in its own separate family, the Sambucaceae.3,14

As if such taxonomic confusion were not enough, there are also differences in opinion about the use of the common name “elder” versus “elderberry.” The older literature commonly uses the term “elder” for the plant, and specifies the plant parts as “elder berry,” “elder leaves,” and “elder flowers.” More recently, the term “elderberry” has taken hold in the literature for the fruit, while “elderflower” is used for the flower. Some authors even use “elderberry flower” in their publications.15,16 The European Medicines Agency takes an interesting approach and uses “elderberry”17 and “elder flower”18 in their official texts, while the second edition of the American Herbal Product Association’s Herbs of Commerce4 specifies that the plant name is “European elder” for S. nigra, and “American elder” for S. nigra subsp. canadensis.

History of Use

The berries of the European elder have been used for a variety of purposes since before recorded history. Archaeological evidence suggestsSambucus canadensis that European elder trees have been cultivated for millennia. For example, elder seeds discovered in what are now Austria, France, Italy, and Switzerland have been dated to the Stone and Bronze Ages (1,000–4,000 BCE).19-22

Elder berries have a long-standing use in herbal medicine. Information on the healing properties of the berry can be found often in writings that date back to antiquity, including in the works of Hippocrates (ca. 460–370 BCE), Pliny the Elder (ca. 23–79 CE), and Dioscorides (ca. 40–90 CE).13 All parts of the elder tree were used as medicine in medieval Europe with a wide range of indications. John Parkinson’s Theatrum Botanicum of 164023 includes extensive descriptions of the therapeutic uses of the various parts of the elder tree. Parkinson noted:

[T]he berries also greene or dry, expell the same [choler and tough phlegme] humors [as the inner bark] and is often given with the same successe to helpe the dropsie, by evacuating great plenty of waterish humors. … [T]he decoction of the roote cured the biting of the viper or adder, and also of a mad dogge, and mollified the hardnesse of the mother, if women sit therein, and openeth the veins, and bringeth downe their courses: the berries boyled in wine performe the same effects; the haire of the head or other parts, washed therewith, is made blacke. … [T]he juyce of the berries boyled with a little honey, and dropped into the eares, easeth the paines of them; the decoction of the berries in wine, being drunke, provoketh urine.23

Similarly, several parts of the American elder were used in traditional medicine systems of many indigenous peoples, especially those in the northern and northeastern areas of North America. The Cherokee and Iroquois nations made preparations of American elder berries to treat fevers, and the Cherokee and Rappahannock for rheumatism.12,24 Berries were also employed by several tribes (e.g., the Haisla, Hanaksiala, Mi’kmaq, and Paiute) for gastrointestinal problems.24 For example, the Miꞌkmaq consumed the berries as a purgative and an emetic,12 and the Paiute ate dried ripe berries to treat diarrhea.24

While many of these uses and indications have disappeared over time, the flowers and fruits of elder trees are still widely used in traditional herbal medicine.25 Elder berries are mostly used in the form of a juice or a syrup as a mild laxative, diuretic, and diaphoretic agent for the common cold.13,25,26

Cultivars and Chemistry

Elder trees are grown as ornamental or fruit-producing plants in many areas of Europe, northern Africa, eastern Asia, and North America. Commercial interest in elder berries and flowers has led to the development of many elder cultivars.27 Breeding began in the early 20th century and peaked in the middle of the century and led to the creation of several well-known European elder cultivars (e.g., Haschberg, Korsør, Samdal, Sampo, and Samyl) and American elder cultivars (e.g., Adams, Johns, Nova, Scotia, and York). According to industry sources, a number of cultivars are currently used for commercial purpose. For European elder, these include Allesoe, Haidegg, Haschberg, Korsør, Rubin, Sambu, Samdal, Sampo, Samyl, and Tattin, with Haschberg being the most widely used. (T. Borchardt email to S. Gafner, January 22, 2021; M. Bush email to S. Gafner, January 21, 2021) Wyldewood 1 reportedly is the most widely used cultivar of American elder,28 although one industry source suggests that the cultivars Bob Gordon, Pocahontas, and York provide better yields (D. Bennett [INS Farms] oral communication to S. Gafner, February 5, 2021).

Compounds of interest in elder berries include sugars, organic acids, terpenoids, phenolic compounds, and volatile constituents. Several papers have reported the contents of these metabolites, either measured in fresh (fresh weight, FW) or dried (dry weight, DW) fruit. Since elder berries contain between 72% and 78% water,29 a conversion of literature data obtained from fresh fruits to dry fruit can be calculated approximately by multiplying with a factor of four. European elder contains 2.6–10.5 g glucose, 2.6–6.3 g fructose, and 0.05–1.0 g saccharose per 100 g FW of berries.29 The main organic acids are citric acid (10.4–999 mg/100 g FW) and malic acid (7.4–882 mg/100 g FW), with smaller amounts of tartaric and shikimic acids. Ursolic and oleanolic acids are the most important triterpenoids in the berries.29

Sambucus canadensisWith regard to elder berry constituents, the focus has been mostly on the phenolic compounds, which include proanthocyanidins, anthocyanins, flavonol glycosides, and minor amounts of caffeoylquinic acid derivatives (e.g., chlorogenic acid) and simple phenolics. The anthocyanins in European elder are dominated by cyanidin-3-O-glucoside and cyanidin-3-O-sambubioside, with smaller amounts of cyanidin-3,5-O-diglucoside and cyanidin-3-O-sambubioside-5-O-glucoside. Total anthocyanin contents in European elder berries vary between 149-953 mg/100 g FW,29 or between 250–1368 mg/100 g FW depending on the authors.30-33 Flavonol glycosides include mainly rutin (29.0–52.0 mg/100 g FW) and isoquercitrin (6.4–26.5 mg/100 g FW),30,33 with small amounts of kaempferol- and isorhamnetin-3-O-rutinosides and 3-O-glucosides.

American elder berries contain similar amounts of sugars and organic acids. Thomas et al (2015)34 reported glucose and fructose concentrations of 1.4–2.6 g/100 g FW and 1.4–3.1 g/100 g FW, respectively. Citric acid and malic acid contents were 163–501 mg/100 g FW and 194–441 mg/100 g FW, respectively.34 Rutin concentrations reportedly range from 3.5–170 mg/100 g FW.34,35 Rutin is the predominant flavonol in American elder berries as well; however, Thomas et al found slightly higher amounts of isorhamnetin-3-O-rutinoside (1.4–16.9 mg/100 g FW) in three out of nine cultivars.34 Isoquercitrin concentrations were 0.4–48.5 mg/100 g FW.34,35

Contrary to the European elder, the anthocyanin profile in American elder berries is dominated by cyanidin-3-O-[6-O-(E)-p-coumaroyl]sambubioside-5-O-glucoside, so the presence of this p-coumaroylated compound can be used as a marker to distinguish among the species. Other anthocyanins in American elder include cyanidin-3-O-sambubioside-5-O-glucoside, cyanidin-3,5-O-diglucoside, cyanidin-3-O-glucoside, cyanidin-3-O-sambubioside, and cyanidin-3-O-[6-O-(Z)-p-coumaroyl]sambubioside-5-O-glucoside. Total anthocyanin concentrations in American elder berries range from 208–1005 mg/100 g FW.31 Concentration ranges of individual anthocyanins are provided in Table 1. The anthocyanin profiles of S. cerulea and S. ebulus appear to be similar to the profile of S. nigra. No quantitative data on individual anthocyanins in S. williamsii was available from the literature, although Feng et al (2016) obtained a total anthocyanin content of 32 mg/100 g FW and included an anthocyanin profile identifying cyanidin-3-O-(E)-p-coumaroylsambubioside-5-O-glucoside as the major pigment in this species.36 No other literature references about the anthocyanin profile of S. williamsii could be retrieved.

Table 1. Concentrations of Selected Anthocyanins in Berries from Various Elder Species (in mg/100 g FW)30-33,37

 

Cyanidin-3-O-glucoside

Cyanidin-3-O-sambubioside

Cyanidin-3,5-O-diglucoside

Cyanidin-3-O-sambubioside-5-O-glucoside

Cyanidin-3-O-[6-O-(E)-p-coumaroyl]sambubioside-5-O-glucoside

S. canadensis

0.3–62.7

1.7–39.4

6.3–94.6

40.8–195

130.6–594.2

S. cerulea

2.9

63.4

n.d.

n.d

n.d.

S. ebulus

84.5

244.8

91.6

42.0

n.d.

S. nigra

44.8–739.8

122.2–630.8

5.9–47.1

16.0–82.6

n.d.

n.d. = Not determined

The Elder Berry Market

While elder berry has a long history of use in traditional medicine, the appearance of commercial dietary supplements and herbal medicines with the fruit has been a rather recent phenomenon in countries with a tradition of Western herbal medicine. The Galenica Codex of 1992,38 a book with all medicinally used preparations for pharmacists in Switzerland, does not list any product containing elder berries. One of the first commercial elder syrups, Sambucol® (initially produced by Razei Bar Industries, Ltd.; Jerusalem, Israel and now owned by PharmaCare; Warriewood, NSW, Australia), was launched in 1992.39

Elder first appeared in the American Botanical Council’s annual HerbalGram Herb Market Report in 2008, when it ranked as the 16th top-selling dietary supplement ingredient in the mainstream multi-outlet channel, also known as the mass-market channel.40 At that time, retail sales from only that channel were reported. The ranking may be due in part to the popularity of elder flower extracts in many cough lozenges, some of which are also included in the dietary supplement category. A marked bump in popularity was seen from 2017–2018 (Figure 1), mainly driven by sales of elder berry products. This increase may have been caused in part by the severe 2017–2018 influenza season and a 2016 clinical trial showing a reduction in symptoms of the common cold using elder berry.41 This positive sales trend has continued, and based on available data, 2020 has been another record-breaking year for elder product sales, with an estimated growth of approximately 200% over 2019 sales.42

Figure 1. US Sales of Elder Dietary Supplements from 2011 to 201943-51
Figure 1. US Sales of Elder Dietary Supplements from 2011 to 2019

There are numerous different elder berry preparations on the market (Figure 2). Many commercial elder berry extracts are standardized to their anthocyanin contents, and extract prices vary based on the concentration of anthocyanins. In 2021, pricing of wholesale bulk elder berry extract containing 7% anthocyanins was between $160-190/kg, while costs for extracts containing 14% anthocyanins ranged between $270-300/kg (C. Tower [Artemis International], email to S. Gafner, February 4, 2021). In contrast, “elder berry” extracts that have been found to be adulterated with black rice (Oryza sativa, Poaceae) extract are sold for as little as $14/kg.

Figure 2. Elder Berry Dietary Supplement Ingredients Available in the United States
Figure 2. Elder Berry Dietary Supplement Ingredients Available in the United States
The Brix value indicates the number of grams of sucrose present per 100 grams of liquid (e.g., elder berry juice with 10 °Brix contains 10 g sucrose in 100 grams of juice). This figure has been modified from Monagas (2021).52

Adulteration

As the popularity of elder berry dietary supplements continued to rise during the COVID-19 pandemic due to consumers’ increased interest in herbal ingredients with purported immunomodulatory and antiviral effects, shipments of some elder berry ingredients were delayed due to manufacturing closures in China and India and disruptions in transportation and material processing at customs.53,54 In response, some industry members started to raise concerns about demand outpacing supply and that some of the elder berry bulk extracts and finished dietary supplements offered during the pandemic were of low quality or adulterated.55-58

However, no data explicitly reporting adulteration of elder berries or elder berry extracts could be retrieved in the published scientific literature at the time of this writing (February 2021). On the contrary, some papers have suggested that elder berry extracts themselves have been used as adulterants, as undeclared color additives to wine59,60 or to adulterate bilberry extracts.61,62 However, the results of the analysis of commercial elder berry products detailed in the a 2016 doctoral dissertation by Joseph Galetti, PhD, suggest that, at that time, elder berry product adulteration was common, even if such adulteration appears to have gone unnoticed by the author.63 For his graduate work, Galetti analyzed 29 commercial elder berry dietary supplements, three samples of bulk fruit, and one sample of bulk powder sold in the United States (n = 31), Ireland (n = 1), or Switzerland (n = 1) for their content of sugars, anthocyanins, organic acids, vitamin C, and total proanthocyanidins.

The finished dietary supplement samples included 14 syrups, five tinctures, four lozenges, three concentrates, and three capsule products.Sambucus nigra Eight of these samples (two products each of the syrups, tinctures, capsules, and lozenges) were found to contain peonidin, peonidin-3-O-glucoside, or peonidin-3-O-galactoside, which are anthocyanins that have not been found in elder berry. Additionally, the elder berry bulk powder contained mainly cyanidin-3-O-glucoside and peonidin-3-O-glucoside, reminiscent of the main anthocyanins found in black rice extract. In the case of an elder berry capsule supplement, the authors noted that the product had an anthocyanin composition that was not indicative of elder berry, with 80.5% cyanidin-3-O-glucoside, 11.6% cyanidin-3-O-galactoside, 3.4% cyanidin-3-O-arabinoside, 2.9% cyanidin, and 1.7% peonidin-3-O-glucoside (calculated as percent of total anthocyanins).63 The product also had an unusually high level of isocitric acid. Galetti hypothesized that this could be due to the freeze-dried blackberry (Rubus spp., Rosaceae) fruit that was also present according to the label. However, peonidin-3-O-glucoside is not known to occur in elder berries or blackberries.64

Another spurious anthocyanin profile was reported in a 2018 paper on the antioxidant, anti-inflammatory, and cytotoxic effects of an “elder berry” extract.65 The extract, described by the authors as a “dietary supplement widely available on the world market, that contains fruit elderberry extract Sambucus williamsii Hance” contained 88.2% cyanidin-3-O-glucoside and 9.7% peonidin-3-O-glucoside, again suggesting adulteration with black rice extract.65

Current Industry Data Regarding Elder Berry Authenticity

In order to assess the current market situation with regard to the authenticity of commercial bulk elder berry extracts and finished products, a request for analytical data was sent to manufacturers of elder berry dietary supplements and contract analytical laboratories.

Methods

In total, 14 companies were asked to participate in this initiative, or voluntarily provided analytical data on elder berry quality. This included eight contract analytical laboratories that specialize in identification of botanical ingredients, three manufacturers of elder berry supplements, and two elder berry extract suppliers. These parties were asked to share data on elder berry analysis in unredacted or redacted form, (i.e., without the name of the supplier or manufacturer in order to respect confidentiality agreements). Eight organizations provided data from elder berry analyses, of which six shared actual reports of the analysis, while the other two shared top-line data on the number of samples that failed identity specifications. The data obtained represent a total of 532 samples, although some of the same samples may have been tested at several laboratories. Test samples included bulk extracts, bulk whole or powdered elder berries, and finished dietary supplement products. Methods of analysis included high-performance thin-layer chromatography, (HPTLC, n = 510), high-performance liquid chromatography with visible detection (HPLC-Vis, n = 50), ultraviolet/visible spectrophotometry (UV/Vis) with chemometric analysis (n = 6), and DNA-based identification using whole genome sequencing (WGS, n = 2). Two laboratories used a combination of HPTLC and HPLC-Vis.

Results

A total of 58 (10.9%) of the 532 samples failed the identity test specifications due to differences in the analytical fingerprint when compared to authentic samples. Adulterated materials were more frequently seen when elder berry manufacturers analyzed competitors’ products (Table 2).

Table 2. Results of Elder Berry Product Testing

Company*

Method

Adulterated/

Failed Identity Test

Total

Alkemist Labs

HPTLCb

32

369

Artemisa

HPTLCb/HPLCc

4

11

DNA4 Technologies

WGSb

0

2

Eurofins

HPTLCb

2

55

Gaia Herbs

UV/Visb

0

6

Nature’s Way

HPTLCd/HPLCc

16

33

Naturex

HPLCb

4

10

NSF International

HPTLCb

0

46

Total

58

532

* Companies in bold included competitors’ products in their analyses.

a Analysis performed by Alkemist Labs (HPTLC) and Complete Phytochemical Solutions (HPLC)
b Proprietary method
c United States Pharmacopeia (USP) European Elder berry dry extract monograph66
d Institute for Nutraceutical Advancement method

Identity of Adulterants

Two companies attempted to characterize the identity of the adulterant. Both companies identified black rice extract as a common adulterant based on comparison of the anthocyanin fingerprint with authentic black rice extract (Figure 2),67 or comparison to published data on the anthocyanin composition. The main anthocyanidin in black rice extract is cyanidin-3-O-glucoside. It also contains small amounts of peonidin-3-O-glucoside, and traces of cyanidin-3,5-O-diglucoside and cyanidin-3-O-rutinoside, but lacks the characteristic cyanidin-3-O-sambubioside present in some of the authentic commercial elder berry species (Table 1).68,69 While there were other adulterants detected in some of the bulk extracts (Figure 3), the identities of these ingredients were not determined. Additionally, several commercial elder berry bulk extracts and dietary supplement products were highly diluted or did not contain any detectable anthocyanins at all.

Figure 3. HPLC-Vis Chromatogram of Authentic Elder Berry Extract and a Bulk ‘Elder Berry’ Ingredient Containing Black Rice Extract
Figure 3. HPLC-Vis Chromatogram of Authentic Elder Berry Extract and a Bulkt 'Elder Berry' Ingredient Containing Black Rice Extract

Figure 4. HPTLC Analysis of Commercial Elder Berry Extracts
Figure 4. HPTLC Analysis of Commercial Elder Berry Extracts
Lanes 1–2: Authentic European elder berry
Lane 3–6: Commercial elder berry products
Lane 7: Authentic European elder flower
Lane 8: Authentic blue elder berry

Sambucus nigraOne of the recent changes in the US dietary supplement market is the appearance of extracts labeled to be made from the fruit of Williams elder, which is a red-berried elder species that grows in northeastern China, Japan, and Korea.70 Unlike the modern herbal use of European and American elder, where the flowers or the berries are the plant parts of interest, traditional Chinese medicine employs Williams elder twigs. Called jie gu mu in Chinese, these twigs are used in combination with other herbs to treat bone fractures.71-73 Williams elder stems and branches are also used in Korean traditional medicine in patients with broken bones and for the treatment of osteoporosis.74 During the course of this initiative, four bulk samples claiming to contain Williams elder berry extract from two different suppliers were analyzed by HPLC-Vis and/or HPTLC. In the case of one supplier, the samples were found to contain either black rice extract or a mixture of black rice and European elder extracts. The samples from the other supplier had exactly the same anthocyanin composition as European elder berry, thus contradicting the findings by Feng et al,36 who reported cyanidin-3-O-(E)-p-coumaroylsambubioside-5-O-glucoside as the main anthocyanin (see “Cultivars and Chemistry” section), with other acylated anthocyanins as minor compounds. As such, it is not clear if the second set of bulk samples were European elder mislabeled as Williams elder or if the research by Feng et al was carried out on the wrong species. To further complicate matters, S. williamsii is included in Bolli's very broad circumscription of mostly red-fruited species under S. racemosa, along with 34 other synonyms.10 Clearly, other species or variants could be involved in commercial supply chains or laboratory studies, absent a voucher specimen. Further investigations into the composition of Williams elder berries are needed to provide clear criteria on how to distinguish among Williams elder and other Sambucus species.

Stability Considerations

Anthocyanins are known to be prone to oxidation, with light, temperature, water content, and pH affecting their stability,75-78 particularly in liquid formulations.63,78 Substantial degradation has also been observed in berries from some suppliers that sterilize fruits, usually by steam, before sending them to manufacturers who then make syrups and extracts. These berries are crispy and have a burnt aroma and flavor (R. Upton [American Herbal Pharmacopoeia] email to S. Gafner, February 8, 2021). Steam sterilization treatments may also noticeably change the anthocyanin profile,76 leading to a more brownish colored product due to the loss of anthocyanins and the formation of various types of polymers.79,80 As mentioned above, several of the bulk extracts did not exhibit any detectable anthocyanins. It is possible that some of the failing ingredients or products from Table 2 were due to improper manufacturing processes. While not technically adulterated, the anthocyanin degradation may compromise the efficacy of the product.

Conclusion

The surge in popularity of elder berry extracts and dietary supplements, combined with supply shortages and increased raw material costs, has created a situation in which some fraudulent suppliers attempt to gain an unfair market advantage by selling diluted or adulterated elder berry extracts for financial gain. The most common adulterant appears to be black rice extract, but other unidentified materials are used as adulterants as well. While the exact taxonomic status of American elder and European elder is a matter of scientific debate, the two species can be distinguished based on their anthocyanin profile. No mislabeling of European elder with American elder, or vice versa, was observed in commercial bulk extracts or finished products. However, one case suggests possible mislabeling of European elder as Williams elder.

The results of this investigation indicate that responsible manufacturers of herbal dietary supplements have to remain vigilant and actively establish quality control assays that help to detect issues with adulteration, such as the undisclosed fraudulent substitution, dilution, and/or spiking of products, which is particularly important during times of extraordinary sales increases or sudden supply chain dislocations and shortages.

* Another commonly used vernacular name for S. nigra is black elder, or European black elder to distinguish the species from the red elder (S. racemosa). Similarly, American black elder is used for S. canadensis.

Choler (yellow bile) and phlegm are two of the four medieval humors, or body fluids; blood and black bile are the others.  These four humors were believed to have made up the human body’s constitution; An imbalance of the humors was believed to be the cause of disease.

Acknowledgements

The American Botanical Council would like to thank Maria J. Monagas, PhD, senior science liaison of the United States Pharmacopeia, for her contributions to this article.

Image Credits:

All photos ©2021 Steven Foster

Top to bottom: Sambucus nigra, S. canadensis, S. canadensis, S. nigra, S. nigra

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