Hawthorn (Crataegus spp.)

By Heather Irvine

Common Names Hawthorn, Haw, Thorn, Thornapple, Mayblossom, Mayberry, May bush, Hawberry. “Haw” is an old English name for hedge.

Older Names Quick, Thorn, Hazels, Gazels, Halves, Hagthorn, Bread & Cheese. [i]

Herbalist’s narrative Hawthorn is one of those country herbs whose leading quality one might at first describe as benevolent. It is much more powerful though!  A great tree, low and broad in stature, it occurs wild in edge-lands of landscapes or occasionally planted for beauty, especially with respect to its generous white blossoms or deep red fruit in the fall and winter. It serves food and sanctuary to wildlife. Overzealous thorns protect birds and smaller critters from those larger ones which receive a memorable gouge and at best a pause to lick one’s wounds! In and around a Hawthorn’s understory, clumsy human types get so focused on the prize… zeroing in on more flowers or more berries, faster, receiving a poke followed by a clumsier startled retraction. Birds and squirrels laugh at us for sure!

The latinized name for the genus; Crataegus, is derived from Greek, “kratos” for strength and “akis” for sharp, in reference to the thorns, which we will get into later.

If you pick flowers, in May usually, June if it was a cool spring, or you are in the far North, the copious and relatively large, satisfying, five petaled white flowers, sometimes tinged with pink, centered with butter colored stamen and pistils, be careful, this delightful act could turn you into a compulsive wildcrafter. I received this treatment in my early days of herbalism. I now focus on collecting the fall fruit.

In late fall we notice Haw’s, fiercer, more menacing appearance, the thorns of which on some, especially mature trees may be oriented at various discordian directions.

 In the winter this tree is a stoic profile in the landscape, hunkered down, un-yielding in the wind, like a steady traveler of the land. This tree has a distinct look per season.

Similar to apple and other fruit tree crops, some years the fruit are really abundant and other years scarce, or the fruits limp along to ripen, making herbalists anxious.

 The mature fruit is usually dark red, or a combination of light and dark, often blemished, typically darker red spots. There are natural rusts (a type of fungus) that travels on the wind or soil and inhabits the skin and leaves of apple family trees.

I should mention that there are some ornamental varieties of Hawthorn whose ripe fruit is yellow.  That is ok too, but for the cardiac medicine, so far, most choose red.

One day we may find that the flavonoids in the yellow are as good as or better but for now tradition and research on the common type dictates.

 Once you have a good amount of Hawthorn, flower or berry, collected you will find many people who need it, whether they know it already or not. If you are a determined or patient person, or have culinary or fermenting skills, Hawthorn wine, of the flowers or typically fruit, is a preservation option also. Hawthorn berry jam is also in the running for the best way to get the people who really need it to actually take herbal medicines! Alternately, don’t tell them that it’s good for them.

Caveat on Names… Some common and folk names, Whitethorn for example, are additionally used for shrubby varieties, which also bear small firm red fruit. In North American Herbalism, we are usually referring to one of the tree species.

Species  There are at least 280 known species, with 200 of these from Eastern North America. And about a tenth as many each from Eastern Asia or Europe.[ii]  Which species are we referring to most often in Western herbalism? By most accounts; C. oxyacantha, C. monogyna, C. laevigata though this is one of the medicinal plants that is often referred to by genus, Crataegus sp.

Ambiguity about botanical identification should make one uneasy in some cases, but not so with Hawthorn.  As a rose family member we can be confident that both fruit and flower of any species will at least be non poisonous/edible. Also, anywhere trees or shrubs of the genus Crataegus, occur they have been assigned medicinal value. 

Selected Species

Crataegus monogyna native to Europe, Northwest Africa and Asia, and now widespread in North America, possibly the most common. It is a deciduous shrubby tree, with thorns.  It is a taller type, 15-45 feet. Monogyna refers to single seeded.

Crataegus laevigata called English Hawthorn, native to Europe, India and Northern Africa and grown in the US as an ornamental, or medicinal. Described as just 15-20 feet high, leaves are 3-5 lobes and the flowers occur in corymbs, which are clusters, though each flower has the usual five-petaled pattern of the genus.

Crataegus douglasii occurs in the Pacific Northwest and is an upright shrub, with black berries which are 1-2 cm.

Crataegus mollis called downy Hawthorn is widespread in North America, from the East Coast to the Rockies, growing up to 30-40 feet.

Crataegus crus-gali  also called Cockspur Hawthorn and it has thorns but the thornless Hawthorn, var. inermis, is also this species. The leaves may be ovate, ovate serrated or somewhat lobed.  The branches tend to be horizontally oriented.

Crataegus flava also called Yellow Leafed Hawthorn or Yellow Fruited Hawthorn, or Summer Haw, is rare but occurs in the Mid-Atlantic and Southeast.

Species used in Traditional Chinese Medicine

Crataegus pinnatifida- bei shanzha – Northern Chinese Hawthorn

Crataeugus cuneata – nan shanzha – Southern Chinese Hawthorn 

Description/Taxonomy

Less known are the classifications levels between family and genus: 

·        Subfamily: Maloideae

·        Tribe: Maleae

·        Subtribe: Malinae

All of these terms refer to ‘Malus’, the apples, also the name of the apple genus. Many say that the fruits of Hawthorn taste like unripe apples and there are many similar botanical characteristics, including the habit of the trees, the five petaled flowers, though possessing five petals or groups of five is also a shared characteristic at a higher level of taxonomy, the Rose family and in other families.  

So what of this Crataegus genus? The genus is not practically identifiable by leaf shape, as the leaves, though typically dark green and a few centimeters long and wide, and somewhat sharply lobed, may vary wildly in shape, even in one species.

The thorns have it, reaching up to four to five centimeters long, generally smooth, round, very sharp, mostly straight and in color ranging from dusty gray, light brown or waxy orange to reddish brown.  There are thornless or shorter thorned varieties.

The fruit is technically a pome, which is a seed covered in a firm pulp which is covered in a thin, usually smooth and slightly waxy skin. Haw fruit is imperfectly round, firm, and the sepals and remains of the stamen and styles show at the end of forming a papery puckered or flanged star shaped bit, in five parts if intact.

You may ask yourself, how big is a Hawthorn fruit?  To assuage your worries about bringing a very wrongly sized fruit to the table, and being mocked by fellow herbalists, this too is varied.  In the Northeastern US, Hawthorn fruits are between a centimeter to several centimeters. Look for a (roughly) football shaped seed inside.

The main contender for mix-ups are native Crabapples, especially because either may have thorns and the fruit size of crabapples varies also and there are also many species which hybridize freely. Some Crabapples can even hybridize with Hawthorns!  Crabapples typically have ovate leaves, whereas Hawthorn leaves tend to be lobed, typically 3-5 lobes, with an overall triangular or rhomboid shape and serrate on its margin. However, Cockspur Hawthorns Crataegus crusgalli, for example have ovate leaves too and as mentioned, one variety is thornless also.  

Some sources describe Crabapples as apple-like though smaller than apples, compared to the Hawthorns fruit which is more like a berry.  I did not find this useful.  This might be helpful if you are looking at the larger fruited Crabs, with gnarled, dimpled, wild apple like fruit, however there are Crabapples, the Asian types, grown widely all over, which have clusters of small round uniform fruit too. Its a good idea to study Crabapples and Hawthorns that have been identified for you to get a sense of some of the patterns.  A trip to an arboretum or nursey can be helpful.

The flowers can (in some cases) be a good give away, in season, as Crabapple blooms are sweetly perfumed whereas some Hawthorn flowers are fetid, possessing trimethylamine a chemical which resembles, as a singer once named for this same botanical family, once put it, “the carrion of a murdered prey”.  This is not always the case though so it is good to observe trees in various seasons and compare a variety of known Crabapples to known Hawthorns or bring out your botanical keys!

Useful visual resource

That was a lot of detail, better articulated visually. Below is one resource that compares some features in North American, though specifically Northeast species:

(But come back for folk, harvesting, and medicinal uses, which are next!)  

https://naturewalk.yale.edu/trees/rosaceae/cratageus/hawthorn-48

History, Ethnobotany, and Folklore: Although any tree with such a stately appearance in the landscape has been ascribed mythical, symbolic and even magical associations, Hawthorn is a real stand-out.

 For one, it is widely associated with fertility and Mayday celebrations.   

It is one of many said to be the source of the crown of thorns Christ wore, although in this case the stark long thorns on somewhat limber, somewhat brittle branches, artistically depicted, do match the suspect.

There are many more that I encourage you to explore. This alone could have been the topic of a piece of equal length or much greater!

Parts Used: Berries, flowers, leaves, and sometimes tips of branches

Harvest  There are three main parts that can be harvested for teas, tinctures and the like. Primarily we are interested in the flowers (spring), or berries (fall), but leaves are also used, and I have noticed that some of the research using a combination suggests some of the activity is in the leaves. The flowers are gathered when open, typically May. The fruit, in the Northeast US is typically red in mid September and can often be picked until late October, though may become soft, pithy or bruised from cold temperatures. Deep red by firm is the target. You are not concerned with an especially good tasting berry, though it will taste better at this time, relatively. From here the berries can be tinctured, dried, made into glycerite or jam, wine, or frozen. If you had picked the flowers in the spring you would most often tincture them, make glycerite or gingerly dry them for tea, or to be powdered once dry.   

Preparation: Flowers can be carefully dried and stored for a short time for use in tea, or tinctured. The fruit is more robust and lasting in flavor and action and can be dried, frozen, made into jam or wine, but as a medicine tincture, powder or solid extract seem bit more exact. James Green suggests tincturing fresh material at 1:2, 100%, or dry material at 1:5, 40-70% regardless of the part used.[iii] Leaves are sometimes included in teas or tinctures of the fruit or flower.

Tea is best made of flowers or leaves and flowers (basic infusion) the berries can be decocted, or made into wonderful syrups or glycerites.

Cultivation: See yourself doing this? You might want to at first locate some wild trees or chat up gardeners, farmers and naturalists in your area to find at least one giving tree to fuel your Hawthorn preparation production in the interim.

Germination is slow, the seed is adapted to wait for the coaxing of agitation, acidification and scarification (literally nicking the ‘protective’ outer surface with a beak or blade) by the progressive treatment of a bird’s digestive tract or imitation by a horticulturalist. There is an instructive, yet not overly hopeful, video here:

www.gardenersworld.com/how-to/grow-plants/how-to-grow-hawthorn-from-seed/

This refers to the hedge type British Hawthorns but the methods are the same.

Herbal Actions: Cardiotonic, cardioprotective, antioxidant, collagen stabilizing, mild astringent, hypotensive, antiarrythmic, diuretic, hypotensive, anti-ischemic, positively-inotropic, antioxidant. [iv] [v]

One very specific action of Hawthorn is anti-ischemic, related to its documented action of improving coronary circulation, dilating coronary arteries and relieving cardiac hypoxemia.[vi] Ischemia is pain, and if sustained, potentially tissue damage that occurs when a smooth muscle is not properly perfused with oxygenated blood. Believe it or not, this can occur in the heart muscle itself and describes a state that over time can lead to heart attack. It also refers to damage that occurs to the heart as a result of a heart attack.

In western herbalism some consider it the most significant herb for ischemic heart disease,[vii] an epidemic disease with no other outstanding therapeutics outside of the extremes; lifestyle, diet, exercise, and emergency medicine.

Another standout action is positively-inotropic. This term, conventionally describes increasing the contractility of the cardiac muscle.  Those in cardiac medicine may respond with alarm, “How do you control the dose?!”  Hawthorn has a similar effect with a different direct action, slower and gentler also. Cardiac glycosides used in emergency medicine impact the contractile fibers of the muscle directly and instantly, which is to say they immediately elicit a strong contraction of the heart muscle which is useful in controlled doses in heart failure, but can be dangerous.  Hawthorn is different, its positive-inotropic action works by directly affecting cells of the heart muscle also, but it does this by enhancing the availability and utilization of energy by these cells. This has both immediate and long term benefits, in effect helping the body maintain, promote and potentially even repair the function of cardiac cells, proliferating the power of the muscle tissue without increasing its size, which is a favorable outcome.

Hawthorn is an indisputable cardioprotective. The ‘protective’ terms are used with respect to organs or systems and when used correctly tell us a substance is generally safe for use in healthy individuals but has a multitude of preventive effects, and possibly even mitigation and or reversal of damage to tissue and function of a specific organ or system after disease or acute damage.

The ‘protective’ terms usually encompass a group of actions. In this case positive-inotropic, anti-ischemic and hypotensive, together encompass remarkable benefits. In addition, Hawthorn is antioxidant. This is to say components of it reduce free radical damage, a normal occurrence from exposure to oxidizing agents, in the case of the cardiovascular system many are endogenous, byproducts of metabolism or other internal reactions, which we would still like to reduce, as these shortens the longevity of tissue maintenance. You have probably noticed, many brightly colored natural foods are noted for antioxidant value.  Does that mean this is no big deal?

The particular combination of flavonoids in Hawthorn seems to be especially protective to the heart.  Furthermore, specific flavonoids in Hawthorn inhibit an enzyme which is released in states of hypoxia, which would otherwise perpetuate damage from cardiac ischemia, which again, is the reduction of oxygenation to the heart muscle, typically from occluded arteries, which, can lead to heart attack.

What of the astringent and other seemingly minor actions? I have seldom used Hawthorn except for the heart or occasionally as an emotional/energetic remedy. According to the edited Modern Herbal, by Maude Grieve, it was used as an astringent for sore throats, and the diuretic quality was employed in kidney disease.[viii] (The diuretic quality also helps reduce blood pressure, and additionally kidney and heart health are very connected via the control of fluid and electrolytes.)

There are however many other herbs to achieve those two common actions.  Good of you if you consider more uses for Haw, but it is really a standout for the heart!

Constituents

·        Flavonoids (with a relatively high percent of the leaf and flower made of a combination of compounds of this type; 1.78%). A few of the individual flavonoids include; vitexin, quercetin, rutin and hyperoside.

·        Oligomeric procyanidins, 1.0-2.4% in the leaf and flower.

·        Triterpene acids, up to 0.6% in the leaf and flower. A few of these being; ursolic, oleanolic, crataegolic.

·        Phenolic acids; caffeic, chlorogenic & related phenolcarboxylic acids.[ix]

A note about isolated constituents.  In the conventional studies of Hawthorn, effects of isolated constituents proved insignificant. However when whole plant preparations were compared in the same experiments, effects were very significant. [x]  In describing this, David Winston has memorably declared that the active constituent in Hawthorn is… Hawthorn.

Medicinal Use

Hopefully by now you have a good idea when and for whom you would recommend Hawthorn, and why it is so great!  One would be correct to think of it in almost any condition that affects the heart muscle or cardiovascular system in general, particularly if there is hypertension, pre-disposure to heart disease, exposure to factors that perpetuate it, or wear and tear on the cardiovascular system due to age, chronic stress, diet & lifestyle, habits of excess, inflammation or prior cardiac events.  

More often than with the advanced situations described below, you will use it preventively for individuals interested in maintaining cardiovascular health and healthy blood pressure levels. However with more people experiencing and surviving advanced cardiac disease and cardiac events, ie. heart attack, it is helpful to know Hawthorn can be used in individuals with more serious cardiovascular issues also. 

A few more technical descriptions stated by the medial herbalist David Hoffman are paraphrased from the popular reference, Medical Herbalism:

·        Degenerative conditions of the cardiovascular system

myocardial problems such as mild congestive heart failure, coronary artery disease, hypertension

·        Recovery from heart attack, especially in conjunction with other   hypotensives

·        Gradual age-related loss of cardiac function’

These uses again are owed to a multitude of actions:

·        Dilation of coronary arteries – by a multitude of constituents

·        Positively inotropic – by improving energy use of cardiac cells

·        Cardioprotective - effects of specific flavonoids, the particular   combination in Hawthorn is greater than a sum of its parts [xi]

The only time to possibly avoid Hawthorn is with low blood pressure, or conditions where lowing blood pressure could be immediately dangerous, however this is theoretical, due to its use for hypertension. In some specific cases I have been very tempted to recommend it for the heart strengthening activity.  Peers, conventional cautions, conscious, responsibility and prior experience that if one has a hunch or considers a warning about a safety issue, it is best to choose another route, prevailed. 

Allies  

Most often we will see it combined with other cardiac herbs, particularly other diuretics and hypotensives but we will also see nervines with a hypotensive reputation as well as herbs for the energetic or emotional heart combined with Hawthorn.  Examples:

·        Leonurus cardiaca (Motherwort), a nervine and hypotensive

·        Viburnum opulus (Crampbark), hypotensive by antispasmodic quality on the smooth muscles of the vasculature.

·        Melissa officinalis (Lemon Balm), nervine, mildly hypotensive

·        Tilia sp. (Linden), at the juncture of hypotensive, diuretic, nervine and emotional/energetic support

·        Rosa sp. (Rose), as more of an emotional, energetic remedy

Plants used in combination – (for advanced practitioners!):

·         Cactus grandiflorus (Night blooming cereus), a specific advanced low dose botanical medicine, used by advanced practitioners and NDs for a few cardiac disorders including hypotension, low BP. 

·        Convalleria majalis (Lily of the Valley), (caution a known poison), used only in specific advanced cardiac conditions by very advanced specialized practitioners and NDs

·        Lycopus virginiana (Bugleweed), used by advanced practitioners, naturopaths and the like in some cases of tachycardia especially with hyperthyroid  

This last section intended for interest or a reminder for those who were already trained in the use of these three low dose botanicals. For example, the author learned of their use from an experienced Naturopathic Doctor who was first trained in emergency cardiac medicine, in conventional medicine. These are also mentioned in the handbook: “Naturopathic Handbook of Herbal Formula, ed 3” though this alone does not provide enough instruction for their use.[xii]

Cautions and Contraindications

As alluded to in the narrative, one of its great qualities is safety.

A statement directly from “Medical Herbalism”: “It causes no toxicity, accumulation, or habituation, and is safe for long-term use in the elderly” is a statement most herbalists would agree upon. [xiii] The only possible contraindication would be, theoretically low blood pressure, however arguably, the therapeutic hypotensive actions occur in instances of hypertension where strengthening the contractions of the heart muscle improve the efficiency of the cardiovascular system. Already quite sure of its safety, a systematic review of many popular herbal safety references, from conservative to moderately conservative revealed little or no practical safety concerns for this botanical.

The conservative contraindications included possible synergistic effects with digitalis glycosides and beta-blockers. Quoting exactly: “Modification of drug dosage may be required. However, adverse effects are not generally anticipated from this interaction”.[xiv] 

Sampling of Research

Many studies have been conducted with Hawthorn or a combination of its constituents.  This is really just a small sampling of them, and are all clinical trials.

·        Patients in NYHA (New York Heart Association) class II chronic heart failure, taking Hawthorn in the study had significantly less fatigue, stress, dyspnea, and palpitations, whether they were using only Hawthorn leaf and flower extract, or the extract in addition to cardiac glycosides.  With or without the conventional medications, patients did better with Hawthorn. (2238)

·        In another study, also of use of Hawthorn in NYHA class II chronic heart failure patients, those who were give Hawthorn 1 ml of Hawthorn extract needed significantly fewer cardiac glycosides. (395)

·        Diabetics with high blood pressure taking antihypertensive medications and Hawthorn, 39 subjects, given 1.2 grams daily of 3:1 hawthorn flower extract twice daily had significant reduction in mean diastolic blood pressure compared to 40 patients on placebo using the conventional medications in equivalent proportion. (2239)

These and many more studies are cited in Herbal Contraindications and Drug Interactions, Francis Brinker, N.D. and the numbered references are available at: www.eclecticherb.com/emp

Dosage and Method of Delivery

Solid extract of Hawthorn berries is a good item to know about, even if you use no other solid extracts. This concentrated paste of berries. The commercial types are shelf stable, and servings deliver a greater amount of the whole plant preparation than capsules or tincture. Given the safety and gentleness of this herb and the momentous health situation of many who would desire its support, during hypertension and or cardiovascular disease, the solid extract provides a higher dose of the therapeutic components in a more concentrated delivery.

Tincture 2.5 ml, 2-3 times daily, 1:5 40% is a suggested preparation and up to 5ml 3 times daily in acute or severe conditions. [xv]

Infusion: 2 teaspoons dried herb, berries or flower, or leaf and flower, suggested dilution is one cup of water, repeated 3 times daily. [xvi]

Dried herb & powders 0.3 to 1 gram dried herb, as suggested by the British Herbal Pharmacopeia.

Wines, jams and food preparations including powdered herb may also be used on the food/medicine principle, the only practical consideration being that Hawthorn is called hypotensive, though it may only be so in hypotensive individuals, and its hypotensive action is attributed to strengthening contractility of cardiac muscle, (positively ionotropic), improving conditions where hypertension is secondary to weak contractility. The positive inotrope activity is not even closely on the same magnitude as cardiac drugs and therefore homemade herbal preparations of this plant should not be feared.

Summary

Overall Hawthorn is a sound herb to recommend for general cardioprotection, due to its antioxidant content, low hypotensive action in hypertension and specific affinity for supporting qualities of healthy cardiovascular tissue, both blood vessels and the heart muscle. Whether you are healthy, affected by cardiovascular disease or concerned by family health history or personal history of poor cardiovascular health it is gentle enough to implement its use with confidence, whether you are a trained herbalist, novice or consumer.

There are many delicious ways to enjoy Hawthorn fruit or flowers and unlike most other herbs you need not fret about determining the exact species as long as you know you have narrowed it down to Hawthorn.   

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A former foraging frolicker, who aims at answering some of often asked but tougher questions in herbalism, such as, how herbs work and what are the real versus theoretical safety issues.  Heather was not long ago collecting and growing hundreds of medicinal plant species for her small herbal product line: Giving Tree Botanicals.  www.GivingTreeBotanicals.com.  Now in the heart of Boston, she is offering herbal health consultations, classes and informal one on one herbal mentorship for interested persons who have immersed themselves in one or more aspects of herbalism or related topics and want to continue with guidance, regular one on one instruction and encouragement, with the possibility of attending occasional community-building events with other students. Fits your schedule and starts where you are!  

She also teaches Actions and Chemistry for the Vermont Center for Integrative Herbalism, www.VTHerbCenter.org and teaches two for-credit herbal courses, for Johnson State College/Northern Vermont University. She gets a great thrill out of presenting at and simply attending herbal events, from Herbstalk, a bustling educational and community gathering in the Boston area to the annual American Herbalists Guild Symposium and anything in between. She has also begun offering seminars for health professionals, the first of which is called "Supplement Straight Talk" about practical aspects of popular herbs & supplements, and talking to patients about herbs. 

[i] Leyer, C.F. (Eds.). (1971). A Modern Herbal:The medicinal, culinary, cosmetic and economic properties, cultivation and folk-lore of herbs, grasses, fungi, shrubs and trees with all their modern scientific uses. By Mrs. M.Grieve. FRHS. Volume A-H. New York, NY: Dover Publication Inc. 

[ii] Khan, I.A. & Abourashed, E.A. (2011). Leung’s encyclopedia of common natural ingredients: used in food, drugs and cosmetics. John Wiley & Sons.

[iii] Green, J. (2000). The Herbal Medicine Makers Handbook. Freedom, CA: Crossing Press.

[iv][iv] Mills, S & Bone, K. (2000). Principles and Practices of Phytotherapy. London, UK: Churchill Livingston. 

[v] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.

[vi] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.

[vii] Mills, S & Bone, K. (2000). Principles and Practices of Phytotherapy. London, UK: Churchill Livingston. 

[viii] Mills, S & Bone, K. (2000). Principles and Practices of Phytotherapy. London, UK: Churchill Livingston. 

[ix] Blumenthal M. et al. (2003). The ABC Clinical Guide to Herbs. Austin, Tx: American Botanical Council.

[x] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.

[xi] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.

[xii] Herbal Research Publications, Inc. Naturopathic Handbook of Herbal Formulas: A Practical & Concise Herb User’s Guide.

[xiii] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.

[xiv] Mills, S & Bone, K. (2000). Principles and Practices of Phytotherapy. London, UK: Churchill Livingston. 

[xv] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.

[xvi] Hoffman, D. (2003). Medical Herbalism. :Rochester, VT: Healing Arts Press.