In late March and early April 2018 I took my first trip to Turkey, a country with a surprisingly high diversity of plants, especially for a temperate climate. Searching online I found that sources state the number of plant species to be found within the nation are between 9,200 and 11,000, but all agree that a large proportion of them (30% to 35%) are endemic, meaning found nowhere else outside of Turkey. Undoubtedly an even higher proportion of them would be regionally endemic, if you include plants that might also be found in just one or two other countries close by, such as Greece, Cyprus, or Iran. However you define it, there is no doubt that Turkey has the highest number of plant species in the entire Mediterranean region of Europe, Southwestern Asia, and North Africa, which is itself known worldwide for having a grand biodiversity.

The primary purpose of the trip was to see as many bulbs and orchid species as we could in only 9 days, although there are numerous other plant categories that are of interest to the generalized naturalist, which is one way I define my sensibilities when it comes to the natural world. And while the trip was indeed a great success from the standpoint of bulbous plants and other spring-flowering geophytes, this post concerns itself with our chance encounter with a sweet pea, Lathyrus belinensis.

We first came across this plant, commonly called Belin sweet pea in English, after stopping at a rather random site on a side road just off of the main north-south highway along the Antalya Peninsula that provides access to what is often called the Turkish Riviera. (The suffix -ensis refers to where an organism originates from, but a brief search on the word “Belin” does not indicate anyplace with that name in Turkey, so for now it remains a mystery why it has been given this moniker.) We selected the stop simply because there was parking space on the otherwise narrow, winding road and there was a mix of habitats, in which we were hoping to find other interesting plant species. Open meadows mixed with pine forests, Mediterranean shrublands, and rocky limestone slopes in a mosaic of niches that usually proves conducive to seeing a variety of plants. Our quest was also successful in that regard, but that is material for another post at another time.

After spending well over an hour here, photographing several orchids, Fritillaria bulbs, and an interesting root parasite among other things, we wandered slightly up the road past one of Turkey’s numerous graveyards towards a pine forest. There, right along the road on a rocky bank cut by construction, grew this beautiful legume with an overall orange appearance.

A closer look at the flowers shows that the flowers are not really orange per se, but bicolored yellow and reddish, thanks to the dark red veining of the upper standard petals. But at a distance they appear somewhere between orange and apricot.

In this photo you can see the winged stems, leaf stipules, and tendrils. This particular combination plus the flowers made us think that this was probably some sort of a sweet pea belonging to the genus Lathyrus. The common garden sweet pea is Lathyrus odoratus, and this pretty clearly looked like a cousin, although we didn’t know what species it was. Sweet peas are native to the central Mediterranean, in Sicily, southern Italy, and Greece’s Aegean Islands. The common name comes from the sweet fragrance of the flowers, and evidently the fragrance of L. belinensis is noticeably distinct from that of L. odoratus. Common sweet peas have been cultivated since the 1600s, and have also undergone extensive breeding and hybridization efforts since about 1870, especially in England and northern Europe, where numerous cultivars now exist. All that said, what exactly was this peculiar orangeish relative from Turkey?

This was my first trip to the actual Mediterranean region, although to date I have been to three other so-called “Mediterranean climates” in California, Chile, and South Africa. All four of these climates (plus the last one in southwestern Australia, making a total of five such regions globally) are characterized by mild, wet, rainy winters and long, hot, rainless summers. The flora tends to be comprised of numerous woody shrubs, small trees, perennial herbs and grasses, and bulbous plants, although zones exist with larger trees, annuals, and succulents as well. Mediterranean zones are known for their generally great biodiversity, especially in plants, insects, and reptiles. They are also known for their pleasant climates and agricultural productivity, and have long histories of human habitation.

Here’s one thing about most Mediterranean climates, though: There are many invasive species in them, plants introduced from other places (frequently ones classified as Mediterranean themselves) which can have a harsh impact upon several factors such as crowding out native plants and altering fire regimes to be overly frequent, which can in turn drastically reduce biodiversity in these naturally rich ecosystems. Out of the world’s five Mediterranean biomes, California is the one closest to me and the one with which I am most familiar since I live in adjacent Arizona. California also happens to probably be the worst-affected of all of these five zones in terms of extraordinary landscape-wide ecological alternations by humanity, including agriculture, urbanization, excessive fire frequency, and yes, many, many invasive species. A great deal of California’s native heritage has been lost, completely altered by all of these factors, but especially by invasive pests. Most of those golden grasses on the hills and fields of yellow mustard that we so identify with Californian landscapes are not native, having been introduced accidentally or purposefully since the 1820’s and later. The original pre-1800 native flora would have looked vastly different from the way it does 200 years later.

It is against this backdrop of knowing how badly altered Californian landscapes actually are and the desperate straits of survival for many of the state’s rarest species that I went to Turkey and the “original” Mediterranean climate. As such, my mindset was attuned towards assuming the worst about whatever it was we were seeing. I thought that perhaps this unique looking orange and yellow sweet pea was some sort of weed, perhaps an introduced one from somewhere else that favored disturbed roadsides and vacant lots. Being rather unfamiliar with most of the native Turkish flora, I simply had no accurate frame of reference for so much of what I was observing, and ranking whether it was “supposed” to be there or not. The photo above is a small illustration of this mindset, because it shows about four different legumes in the frame, and there were another 3 or 4 at the same site that aren’t included in this photo. Since legumes can be one of the plant families (Fabaceae) with bad invaders in it, I was having trouble discerning natives from nonnatives. I just simply didn’t know.

Well it turns out that this is not a weedy invader, and is in fact an endemic plant. We learned this from Chris Gardner, a British botanist and expert on Mediterranean flora who lives in the Antalya Region where our travels were based. We hired Chris for a day to be our botanical tour guide up a mountain range at the far southern end of the Antalya Peninsula where he would take us to sites where we could view flowering spring bulbs and several rare endemic species.

Chris was full of useful information and spending the day with him was highly educational. One of the things we learned on our day trip with him was that Turkish Mediterranean flora does not actually have a huge invasive weed problem, unlike South Africa and especially California, as I just mentioned. According to Chris, the general Mediterranean region outside of Turkey doesn’t really have this problem either, which surprised me a bit. But he explained it this way: Mediterranean flora has been impacted by humanity for many thousands of years via agriculture, forestry, urban development, and especially grazing, and as a result the flora is robust and competitive and is capable of survival under rigorous conditions. As a result, introduced species from elsewhere in the world are not easily able to gain a foothold amidst native Mediterranean floral communities, and even if they do, they appear to be unable to thoroughly dominate in the way they have been able to in so much of California. Exotic species might insert themselves here and there but appear incapable of taking over.

Of course what we currently see in the actual Mediterranean as a result of these human-induced pressures is what has adapted and survived. It is quite probable, if not nearly inevitable, that before humanity arrived, especially civilized and agricultural versions of us, that the Mediterranean contained many more species that it does today. There would have been species of all sorts, including sensitive ones with specialized lifestyles and narrow habitat requirements. And with the advent of humans, their domesticated animals, and their food production and economic needs, many of these species would have been made extinct. We probably can never really know how much of the prehistoric Mediterranean flora (and animal species like bugs, reptiles, etc) once existed and were eliminated; but due to the long history of human habitation it is likely that the most sensitive ones were lost long ago, by and large leaving behind the tougher survivors, as well as pockets of now-rare types. By comparison, California has only much more recently undergone in the past 200-odd years what Turkey, Greece, Italy, Spain, France, etc experienced thousands of years ago in terms of landscape-wide alterations.

Anyway, back to the Belin sweet pea. During the course of the day tour Chris asked us where we had already been and which plants we might have seen. When we mentioned where we were, he asked, “Did you see the orange and yellow sweet pea? That’s an endemic species to this region.” We mentioned that we had indeed seen it, but we didn’t know anything about it. He said it was a Lathyrus species related to garden sweet peas, but then moved on and we didn’t discuss it again. Meanwhile, I was glad that I had taken some photos of it, although I simultaneously wished I had known what we were seeing and that I’d taken additional photos of it. The five images shown above are the ones I originally took specifically of L. belinensis, before known what it was.

Later on, editing through my photos on a full-size computer monitor, I discovered that I had unintentionally captured a couple of additional photos of the Belin sweet pea. We had wandered through the nearby cemetery and I was busy taking photos of the array of colorful wildflowers growing in the meadows between the scattered graves. My main focus was on the scarlet corn poppies (aka field poppies, Flanders poppies, red or common poppies – all names for Papaver rhoeas) that dotted the fields with their showy blooms, but upon closer inspection I see that the Lathyrus belinensis are in there too. Well it’s fortunate that I got more photos of them in habitat context, not just as close-ups.

As you can see, the Belin sweet peas are mixed in with the poppies, several other legumes, and a number of different, mostly native, wildflowers and what looks like oat grass, an important food crop also native to here. The mountain is Tahtali Dagi, a 7,762 foot / 2,366 meter tall prominence commonly called the Turkish Olympus or Mt. Olympos in English. As a side note, there are lots of cool plants up on the flanks of Tahtali Dagi, but that’s the subject of a future post. Meanwhile, the Belin sweet peas are down here.

And they are literally ONLY here. Upon returning to the United States, my friend and travel companion John discovered that Lathyrus belinensis is an exceptionally rare, narrow endemic found at just one single site on earth. The very site that we stumbled across, not knowing whatsoever what we were seeing at the time. According the IUCN Red List, L. belinensis was discovered by science in the mid 1980s and the species description published only in 1988, 30 years ago. According to a 1995 population survey, there were only about 5000 plants discovered, a figure that had tragically dropped to only 1000 plants by 2010, a reduction of 80%.

The reason for the sharp reduction in population is credited in the IUCN Red List report as being due to a combination of factors, including road construction and infrastructural development associated with the rapid development of the tourism industry in the Turkish Riviera region of Antalya Province; heavy grazing by goats and sheep; and the expansive planting of pine tree plantations for lumber and pulp wood, creating shade which the small sweet peas cannot compete with or survive in. I’ll link to the summation of the IUCN Red List report below:

http://www.iucnredlist.org/details/176094/0

For me, this raises the question of, “Why is this plant so rare?” It is closely related to a common and much more widespread species of sweet pea that has undergone extensive breeding and been spread worldwide, for one. For another, it appears to tolerate disturbed sites reasonably well because we found it growing on a road embankment less than three meters from the pavement, as well as in a periodically mowed area maintained as open in the midst of a graveyard. It has been grown by sweet pea breeders and enthusiasts who have crossed it with L. odoratus in an effort to introduce yellow flowers into the normally pink, purple, lavender, or white flowers of that species. It doesn’t appear to be difficult to grow in captivity, nor does it seem to have specialized habitat requirements. So why is the population down to only 1000 plants or so as of 2010? (In the year we saw it, 2018, the population might even be lower, but we didn’t know enough to go seeking additional plants above and beyond the few dozen we witnessed. I regret our unawareness of its status at the time we saw it. Plus the next day, Chris certainly didn’t emphasize just how rare this plant is either!)

The answer probably boils down to ignorance and/or a lack of a comprehensive plan to save the species from extinction. Some rare species are genuinely difficult to grow outside of a narrow habitat niche for any number of complex reasons, but this would not seem to be the case with L. belinensis. It would appear to me that some combination of governmental assistance and private enterprise in a recovery program would quickly yield massive positive impacts upon the population of this rare plant. Perhaps it was once more widespread thousands of years ago, but was grazed out by livestock, in which case getting a number of new populations established in suitable nearby habitats (even if only on limestone road cuts and rocky outcrops and other cemeteries) ought to be eminently possible as long as they aren’t grazed, or shaded by big pines or other dense shrub cover. The IUCN report says that the entire population of Lathyrus belinensis is found within a 2×2 square km area. I am still amazed that we stumbled upon it! We had zero idea, and this was a needle in a haystack sort of discovery!

It’s important to save whatever genetic diversity remains of this pretty, trailing plant, because the lower the population goes, the less genetic variation will remain. Any plant or animal facing a genetic bottleneck like this is at risk for extinction, since diseases and climate change and other environmental impacts can more easily extinguish the entire species if they are too similar and closely related via inbreeding. Not to mention non-genetic risks such as disastrous storms, flooding, careless grazing, or road expansion. Any one of these things could make the entire species extinct within one year. That’s far too vulnerable and should be corrected.

In closing, it is good to see that at least some plant breeders and horticulturists have taken an interest in L. belinensis by trying to cross it with L. odoratus and get some yellow or orange flower coloration into the resultant hybrids. Getting a yellow sweet pea has been a breeding goal of a number of growers for decades. My online research indicates that hybrids between the two sweet pea species have not resulted in any yellow flowers, but that back-crosses of the hybrids with regular L. odoratus have resulted in some striking new colors and fragrances due to the brand new gene introductions, although none are actually yellow. However it does appear that the hybrids of the two species are resistant to powdery mildew fungus, which is also a positive outcome.

While perhaps a worthy goal, it should be noted that it is also important to preserve the species in its “pure” state, and not excessively dilute the genes with a much more common species. Evolution takes many thousands of years or longer to operate in plants, over time resulting in fascinating divergences and localized adaptations that are part of the collective natural heritage of life on earth. As seen with improved disease resistance, more vigorous growth, greater productivity, and beautiful new color combinations, genetic diversity is a very important aspect of conservation. This is why we should work to save this rare plant (which doesn’t necessarily need to be this rare!) and preserve and increase the population, especially when unlike some species it should be fairly easy to do so.

I will close with a few more photos below of some of the compatriot plants of Lathyrus belinensis found growing right nearby. Thanks for reading and if you can grow this plant, maybe give it a try. Several places do sell seeds online, and although the Turkish government should get more involved, ex-situ conservation by concerned plantspersons and botanical institutions is a critical component of saving this attractive species from extinction.