Guava (Psidium guajava)

A personal experience when I was in my late teens cemented my passion for the botany of food. At that time I was involved in field work on a tropical island where I was undertaking botanical surveys. I encountered a curious plant I did not recognize which had winged stems and rough leaves.

When I brought it back to my professor, I was not a little surprised when he identified the sterile branch with utmost ease as belonging to the guava tree (Psidium guajava).

The professor then proceeded, in a good-natured fashion, to tease me about my ignorance, attributing it to my upbringing as a city kid.

Cherry Guava (Psidium littorale)

This incident, along with a few others, fueled in me the desire to learn of and to try any fruit (which I know is edible of course) to which I am introduced.

The myrtle family (Myrtaceae) was to feature prominently in my fruit hunting adventures as I proceeded to learn of the less well known relatives of the guava, many of which produce palatable fruits.

The Myrtle family is traditionally divided into two subfamilies, one of which, the Leptospermoideae, produces largely dehiscent fruits (well known examples being eucalypts). The other subfamily, the Myrtoideae, produces fleshy indehiscient fruits and is the focus of this post.

Surinam Cherry (Eugenia uniflora)

The American tropics are probably the best to start with, given the concentration of fleshy fruited members of the family there. The guava itself hails from that region.

Though half a world away from the Neotropics, I have had the privilege to sample the fruits of a close relative of the guava, the cherry guava (Psidium littorale). Although the fruits are much smaller than many commercial varieties of the guava, the cherry guava packs a punch with it’s sweet and intense flavor.

Pineapple guava (Feijoa sellowiana)

Surprisingly, there are about 100 other species of Psidium, a fair number of which must serve as useful bush foods where they occur, in the New World tropics. Many of these less well known species are becoming rare or even facing extinction due to habitat loss.

The numerous species of guavas are far from the Myrtle family’s repertoire of edible gifts to man. In South America, the fruits of the well known and large (c. 550 spp.) tree genus, Eugenia, have a large number of edible species.

Jabuticaba (Myrciaria cauliflora)

To this genus belongs a number of famous and patriotically named species like the Surinam Cherry (Eugenia uniflora) and the Cherry of the Rio Grande.

Then there is also the famed Feijoa (Acca) sellowiana (Feijoa, Pineapple guava). So relished are the fruits of this species that it has been cultivated widely temperate regions.

Another genus, Myrciaria (c. 40 spp.) , provide significant commercial fruits locally. The Brazilian Grape tree or Jabuticaba (Myrciaria cauliflora and several other related species) are savoured by the locals.

Rose Myrtle (Rhodomyrtus tomentosa)

Native Guava (Rhodomyrtus psidioides)

At least one species, the Camu Camu (M. dubia), has been gaining prominence on the international market for it’s health promoting properties (see Camu Camu info page).

Numerous other genera with exotic sounding names like Myrteola, Plinia, Ugni and are also sources of edible fruit to peoples of the region.

I await future forays into the American tropics to sample more of these gems of the bush, but I turn now to the Old World tropics, where I was born and where my culinary ‘resume’ is a little more substantial.

In the Indomalayan and Australian tropics, there are a number of guava relatives whose fruits are worthy of mention.

Mempoyan (Rhodamnia cinerea)

Rhodomyrtus, for example, is a small genus of around 11 species. The Rose Myrtle (Rhodomyrtus tomentosa) and what Australians call the Native Guava (R. psidioides) are certainly worth exploring as a commercial fruit crops.

Rhodamnia (c. 28 spp.) is yet another genus with edible fruits. I have tried the fruits of one, R. cinerea (colloquially called Mempoyan), when I was back in Singapore. Edible but not particularly palatable.

Rose Apple (Syzygium samaragense)

The most significant guava relative in the old world tropics must be the prominent paleotropical tree genus Syzygium (see wiki page). In Malyasia these fruits are known colloquially as jambu or kelat.

Some of these species of jambu are well known fruits of the Indo-malaysian region. Examples are Syzygium aqueum, S. malaccense, S. jambos and S. samaragense (variously called water apples or rose apples) which are commercially significant fruits.

Lilly Pilly (Acmena smithii)

The succulence and large plum to fist-sized fruits of these species are undoubtedly responsible for their commercial importance.

The smaller berries of the numerous less known species of Syzygium however, provide a good ad hoc snack while wondering around in the jungle.

In Australia, members of Syzygium are refered to as Lilly Pillies and many species, like in the Asiatic tropics, are well known bush food. There is also another genus, Acmena, which are also referred to as Lilly Pillies in Australia, and I recently had the opportunity to devour quite a sizable quantity of purple berries from a fruiting tree of the Lilly Pilly, Acmena smithii.

Myrtle (Myrtus communis)

By far however, one of the most agreeable fruits of the Myrtle family in Australia belongs to that of Austromyrtus dulcis (see info page), called Midyim by Australian aborgines.

Finally, where better to conclude this account of fruits with the namesake of the Myrtle family – the myrtle (Myrtus) itself.

While more commonly known for it’s medicinal properties, the sweet fruits of this predominantly Mediterranean and North African tree genus is well suited as the icon of the succulent gifts that the Myrtle family has endowed on mankind since the dawn of time.

Lichens are not technically plants but are the result of a evolutionary successful mutualism between algae and fungi. Surely the open minded nature lover can fit lichens into their catalog of ‘loves’.

The raison d’être for including lichens in a blog on economic botany is because lichens have do in fact have uses. This might come as a surprise to some. Welcome to the understudied field of ethnolichenology.

Lichens as food

Umbilicaria sp (Rock tripe). Members of this genus were used as food. Image credit: Jason Hollinger

Don’t look very appetizing to me. Lichens have nonetheless served human as a source of food.

Lichen.com lists some 17 genera of lichens that have been used as food in various countries like India, Japan, North America, Iceland etc.

The use of lichens as food is limited though, due to their mild toxicity (in some) and indigestibility. Even after these problems are overcome, as the aforementioned cultures have, lichens tend to be bitter and have low nutritional value.

Iceland Moss (Cetraria islandica), used in Iceland for food and medicine. Image source: Köhler's Medizinal-Pflanzen (1887)

I read in the SAS survival guide to eat the partly digested lichens in a caribou’s stomach. I look forward to doing that someday (gulps) if I visit Alaska! The caribou’s feeds on lichens from the genus Cladina and for some Alaskans, the fermented lichens in the caribou’s stomach is called ‘stomach icecream’ and is treated as a delicacy.

More directly, the North American tribes used lichens like Rock tripe (Umbilicaria spp.) and Bryoria spp.

Also, the biblical manna of Israelites appears to be a lichen, Lecanora esculenta.

Many other lichens could possibly be eaten in survival situations  but they are usually quite bitter (I haven’t tried) and I won’t claim responsibility if by some slim odds you pick a poisonous one. Bon appetit!

More on lichen uses in the next part of the series.

The Jujube tree. Image credit: Phillip Merritt

When I wrack my brain to pinpoint individual plant species which have a large large number of uses, I can only think of a few (possibly due to ignorance on my part).

The coconut palm (Cocos nucifera)  is one such plant. It is used in virtually all aspects of human livelihood: food, beverage, clothing, construction material, tinder, oil etc.

Another plant would be the neem tree (Azadirachta indica), for the seemingly endless list of pharmacological products it bestows to mankind. Another two are hemp (Cannabis sativa) and soybean (Glycine max). But all these plants are well known and mainstream. Today the star is a humble fruit tree called Jujube (Ziziphus zizyphus).

A childhood association

Dried jujbe fruits, often refered to as red dates in Chinese. Image credit: Marco Schmidt

Ziziphus zizyphus (read about the curious name) hails from the dogwood or buckthorn family (Rhamnaceae) and is cultivated all throughout India, Russia, the Middle East, southern Europe, and especially China.

The plant is not well known in the West. Being Asian however, I am not a stranger to this plant.

As a teen I was a great fan of dried jujube, processed into a sweet and salty snack with the appearance of dirt pellets!

Then also, there was the whole dried jujube fruits called red dates (Hong Zao, 紅棗) which is a familiar addition to chinese soups and medicinal recipes.

I didn’t think there was more to jujube but I was wrong.

The myriad uses of Jujube

The wood is strong, durable and smooth, and has been used to make a wide variety of things ranging from combs to musical instruments to ships.

Incredibly, jujube has been used medicinally for ~3000 years. All parts of the plant has found some form of medicinal use.

Culinary-wise, the fuits of jujube has been consumed in just about every conceivable mode: candied, dried, fresh, in teas etc. Jujube is also used to make wine and vinegar and is a major source of honey in China. What a variety of flavours!

Whats left of the jujube tree can also be used as fodder for cattle, camels and goats.

Would it be then that jujube is less cultivated and known because it is a fastidious tree?

Hardly.

Jujube is cold hardy, takes to a wide variety of soils and tolerates a wide pH range. It has few pest and fruits precociously. The only few problems might be potential weediness and susceptibility to certain fruit flies in some places – nothing, I’d say, that can’t be fixed with some effort in selection.

I am exhausted already but I haven’t exhausted Jujube’s list of uses (see more here)!

References

Outlaw, W.H., et al. (2002). The Jujube (Ziziphus jujuba Mill.), a multipurpose Plant. Economic Botany 56, 198-200.

(see also Wiki article)

Of all the branches of botanical sciences, ethnobotany or economic botany could be considered the most immediately expedient to humankind. In almost any original ethnobotanical study from a previously unstudied area, researchers will document the potential culinary, medicinal and practical uses of a myriad plant species. And yet, the diet of the average modern human is depauperate in botanical diversity. Antibiotics continue to be prescribed, only as a selective device for antibiotic-resistant microorganisms. Fossil fuels are still used as the primary source of energy for automobiles. We construct furniture from the last survivors of rare tropical dendrons.

Admittedly, the world is slowly catching up with advances in biofuel and alternative sources of energy. Against the backdrop of decades of accumulated knowledge however, humankind is far from developing a praxis.

We must all start with ourselves – whatever small deeds we can do.In the face of circumstances which I have no apparent power to change (eg, climate change, economic recession), I choose to do what I enjoy. I am not the ethnobotanist in the field. I am not the farmer who must choose between corn or switchgrass for increased biofuel yield. I am the last person to advise political decisions. But, I can choose to try that wild berry that is stated in a local plant guide to aborginal food. The day might come where a platter of bush fruits compliment my dinner. I can choose to consult a herbal for minor ailments that needn’t concern a doctor. And as the opportunity arises, I can choose to use of sustainable biofuel over fossil fuel.

Envision a world where modern man incorporates more bush food into their cuisine. Imagine the widespread use of herbal remedies in the household setting. Hold in anticipation a world freed of the tyranny of fossil fuel over-reliance. The living praxis of economic botany research begins with the individual!

Ocimum gratissimum (Wild Basil), one of the many herbs used to treat STDs in Uganda

I was reading an article on the use of medicinal plants in Uganda. In a 3 year study at an area around the Queen Elizabeth Biosphere Reserve in Bushenyi and Kasese districts in western Uganda, the authors of the article documented 67 species (in 27 families and 51 genera) the inhabitants used for treating fungal and bacterial infection, particularly bacterial and fungal infections associated with sexually transmitted diseases (STDs). The authors mentioned that even though the cost of modern medicine for STDs had dropped, such prescriptions would still be too expensive for most in the region to afford. 80% of the population in Uganda still rely on herbal remedies.

Most of these were herbs and a large proportion of the species belonged to the mint (Lamiaceae) and daisy families (Asteraceae). Many of the herbs were taken orally or applied topically. Species of Lamiaceae (eg Ocimum, Plectranthus) in particular, were prepared by steaming and subsequently inserted into the birth canal.

The medicinal efficacy of many of these plants have yet to be validated in the laboratory, yet, the use of such remedies must have gone on for quite a while.

More ethonobotanical research and conservation effort would be pertinent to ease the pressures on the wild population of some of thse plants, which are often illegal harvested and sold.

References

Kamatenesi-Mugisha, M, Oryem-Origa, H, Odyek, O and
Makawiti, DW (2008). Medicinal plants used in the treatment of fungal and bacterial infections in and around Queen Elizabeth Biosphere Reserve, western Uganda. African Journal of Ecology 46, 90-97.

Image copyright of Harvard University

While browsing through ethnobotanical websites, I stumbled on a webpage with an interview with Richard Evans Schultes (January 12, 1915 – April 10, 2001).

A student and later Professor of Harvard, Richard Schultes undertook his life work in the Amazon, working with medicine men of the region and for almost two decades, made an enormous collection of over 30000 plant specimens, around 300 of which were new to science.

His ethnobotanical works culminated in numerous scientific publications and popular works, sch as The Plants of the Gods: Their Sacred, Healing, and Hallucinogenic Powers (1979), co-authored with chemist Albert Hofmann.

He is remembered fondly by legions of his students for is encyclopedic knowledge, kind and encouraging disposition and probably most of  all, his immaculate skill with an 8-foot long Amazonian blowpipe! I wish I were born earlier so that I would have had the opportunity to have attended his lectures where he routinely made such demonstrations.

By today’s standards, the achievements of Richard Schultes are legendary indeed.  This blog post is way too brief to cover the maestro’s life and achievements. More may be found in the following links (here and here).

Suffice it to say that as a result of his achievements he is, and rightly so, considered by many to be the father of modern ethnobotany.

In true Einstein brevity, I proclaim, as other before me have:

Plants = Life

So, in essence, this blog will be on how our lives are tied in with plants. Now, to begin this endless discovery…