“The beginning of wisdom … is knowing things by their right name.”

This saying from the Chinese philosopher Krishtalka is a good lead-in to this discussion of how Carl Linnaeus has helped horticulture. Linnaeus gave us the first organized system of Latin binomials for naming living organisms. Before you take his name in vain – or in the vein of “Latin is a language/as dead as dead can be/first it killed the Romans/and now it’s killing me” – think of how it was before Linnaeus.

Linnaeus to the rescue

The system of Carl Linnaeus, laid out in Systema Plantarum (“The Species of Plants”) in 1753, actually helped reduce confusion. At the time, Latin was used as the universal language of science. As Michael Dirr points out in his Manual of Woody Landscape Plants, even today there are more than 245 names for the white water lily (Nymphaea alba) in the English, Dutch, German and French languages alone. All for one single plant – Nymphaea alba – named, in fact, by Linnaeus.

Photo by Ken Chamberlain, OSU.

So the use of Latin helped to alleviate the confusion between, for example, French and English botanists (and subsequently horticulturists). Usage of an official, two-part name then helped reduce the tangle of words and the written form of logorrhea that existed up until 1753. Consider, for example, the briar rose, which Linnaeus named Rosa canina. Clean, clear, simple. Prior to Linnaeus’ intervention, though, the plant was described by some as Rosa sylvestris inodora seu canina or by others as Rosa sylvestris alba cum rubore, folio glabro.

We think you can agree that the system of Linnaeus was easier to use.

Teach our children well! Second graders in awe of spiders? Video machines? Monkeys? No, the glory of trees-umbrella magnolias. They now even know the Latin binomial, Magnolia tripetala.
Photo by Ken Chamberlain, OSU.

It takes two

Linnaeus also arranged species and genera (groups of related species) into a hierarchical system, with bigger groups of plants in classes and orders and kingdoms, such as the Plant Kingdom and Animal Kingdom. At the core of the system is the idea: species = reproductively isolated populations of organisms.

Species are represented by a Latin binomial, a two-part Latin name, comprising the genus name (with the first letter capitalized) and the specific epithet (with the first letter not capitalized).

Both parts of the name are italicized or underlined. Let’s look at a few simple examples: Quercus is the genus for oak. Quercus alba is the Latin binomial for the species we also know as white oak; the “alba” part of the name means white. Populus alba, then, is the white poplar. Quercus alba = white oak, and Quercus palustris = pin oak.

The system works for animals as well: Agrilus planipennis is the emerald ash borer, Agrilus anxius is the bronze birch borer, and Homo sapiens is us – the species known as human beings. None of these species will mate with each other; they are reproductively isolated from each other.

Occasionally nature is a bit messy, of course. Acer rubrum, or red maple, is considered to be a good species by plant classifiers, and so is Acer saccharinum, the silver maple. Nevertheless, as horticulturists we know that sometimes these two species do indeed hybridize, and we know these as Freeman maples, designated either as Acer rubrum × Acer saccharinum or as Acer ×freemanii. Popular types of Freeman maples include Acer ×freemanii ‘Autumn Blaze’ and Acer ×freemanii ‘Armstrong’.

It’s all relative

Leaf cutter bee damage is evident on Eastern redbud. These bees are a species in the genus Megachile, and they are in the insect order known as Hymenoptera (bees, wasps, ants). Eastern or Canadian redbud is Cercis canadensis in the plant family Fabaceae (the bean family). All of this name and classifi cation information helps organize our knowledge about these organisms.
Photo by Jim Chatfield.

Biologically related (yet reproductively isolated) species, such as red maple (Acer rubrum) and Japanese maple (Acer palmatum) are in the genus Acer. Again, a genus is a group of related species. Related genera were later put into a new classification category known as a “family” not described by Linnaeus in 1753. For example, the rose family (Rosaceae) includes such related genera as Rosa (rose) apple (Malus), mountainash (Sorbus), hawthorn (Crataegus) and many others. Knowing this helps with plant problem diagnostics and infectious disease control. For example, bacterial fireblight occurs only on genera in the rose family.

This information of relatedness also comes in handy, for example, when you consider early host studies conducted once the emerald ash borer became a problem in North America. Plants in the olive family (Oleaceae) include such genera as Forsythia, Syringa (lilac), Chionanthus (fringetree), several others – and Fraxinus (the true ashes). The first place to check to see if the emerald ash borer (Agrilus planipennis) had a broader host range was to do feeding studies on genera related to Fraxinus in the Oleaceae family.

So, forsythia and lilac and others were checked. None seem to be hosts in nature for the emerald ash borer, which is restricted to the genus Fraxinus. Note that mountainash was not looked at as a potential alternate host in the studies, because even though it has “ash” as part of its name due to some similarities in its leaf structure (compound), it is not in any way closely related to true ashes. Indeed, as you saw above, Sorbus (in the Rosaceae) is not in the same plant family as Fraxinus (in the Oleaceae).

A little OCD?

Linnaeus truly did love to organize, being the original naming authority for more than 4,000 animals and 8,000 plants. He even developed a soon-abandoned system for giving Latin binomial names for rocks! He did hate fungi, however, since they were mostly microscopic, hard to study in the 1700s and often hard to link up their sexual and asexual stages. He therefore declared in exasperation that there was only one species of fungus – Chaos fungorum. Fortunately we have come a long way since then, and the Latin binomial system is now used for fungi; for example, Venturia inaequalis for the apple scab fungus and Ceratocystis fagacearum for the oak wilt fungus.

Linnaeus was proud of his classification and naming expertise and somewhat grandly declared of his efforts: “Deus creavit; Linnaeus disposuit” – God creates; Linnaeus organizes.

He did, however, have his humble streak, knowing his (and everyone’s) place in the world. As related in a wonderful essay by Kennedy Warne in the May 2007 issue of Smithsonian magazine that marked the 300th anniversary of the birth of Linnaeus: in 1762, when Linnaeus was made a member of the Swedish nobility and given the name “von Linne,” “… he chose for his heraldic emblem an unprepossessing Lapland flower, Linnaea borealis, a plant named after him and described by him as ‘lowly, insignificant, disregarded, flowering for a brief space … from Linnaeus who resembles it.'”

A true, stubborn Swede

It is true that Linnaeus did have a contrary streak. The following story comes from a neat webpage (www.ucmp.berkeley.edu/history/linnaeus.html):

Linnaeus enjoyed waxing poetic about the male and female parts of flowers, writing once that: “The flowers’ leaves … serve as bridal beds which the Creator has so gloriously arranged, adorned with such noble bed curtains, and perfumed with so many soft scents that the bridegroom with his bride might there celebrate their nuptials with so much the greater solemnity.” This led to critics such as Johann Siegesbeck, who talked of the “loathsome harlotry” of the Linnaean parallels between plant and human love images.

To which Linnaeus responded with the following comeuppance to Siegesbeck. “He named a small, useless European weed Siegesbeckia.” Similarly, he is reported to have named what he considered the common, mundane dayflower Commelina communis after his colleague Commelinius – whom he thought to be, well, common and mundane.

Having said this, there is a saying of Linnaeus that we think is a great motto we should all follow when it comes to our horticultural interactions with each other:

“If you have remarked errors in me, your superior wisdom must pardon them. Who errs not when perambulating the domain of nature? Who can observe everything with accuracy? Correct me as a friend, and I as a friend will requite with kindness.”

What a thought – to perambulate nature with Linnaeus himself.

One last story from the Kennedy Warne essay: He speaks of Linnaeus and the nature walks he led in the mid 1700s: “What forays they must have been! Botanizing with Linnaeus would have been the equivalent of studying geometry with Euclid, or taking a writing class from Shakespeare. In keeping with Linnaeus’ orderly disposition, the expeditions were organized with the precision of a military campaign, with designated note takers, specimen collectors, and bird shooters. A bugle would sound when rare species were found. At the end of the ramble – up to 12 hours during the Baltic summer months – the party would troop back to town, waving banners, blowing horns, and beating kettledrums. At the botanic garden a shout would go up, Vivat Linnaeus!

A debt of gratitude

So, Linnaeus was the Elvis of his day. We owe him big time. Enjoy those Latin names.

Let Liquidambar styraciflua (sweetgum), Narcissus poeticus and Orchis spectabilis flow trippingly off your tongue. Appreciate the light that goes off when you realize that Philodendron was named from the Greek (and the Latin) “phileo” (to love) and “dendron” (a tree), since many plants in this genus have a vining growth habit. Or that Gypsophila comes from “gypsos” (lime) and “philos”(loving), since baby’s breath prefers an alkaline soil. Concur with the consensus that Theobroma cacao makes great culinary sense as you realize that Theobroma translates to “food of the gods”.

Finally, cannot we all as horticulturists agree with the great horticulturist Liberty Hyde Bailey (who also gave us the horticultural concept of cultivar for cultivated varieties – but that is another story) when he said:

“‘What’s in a name?’ cries Juliet. ‘That which we call a rose by any other word would smell as sweet.’ Yet Shakespeare might admit that a rose is not less sweet because we know its name.”

The next time someone phones to ask you if a red maple is a good plant selection for a sunny, hot and wet site, keep in mind the importance of your knowledge of the nuances of plant names. Does the caller really mean red maple (Acer rubrum) or does he mean a red-leaved Japanese maple (such as Acer palmatum ‘Bloodgood’)? Knowing which is good for that sunny hot, wet site truly matters – that’s the rub.

Vivat Linnaeus!

The authors comprise part of The Ohio State University Extension Nursery Landscape and Turf Team. Jim Chatfield is state extension specialist in the Department of Plant Pathology and Department of Horticulture and Crop Science at the OARDC in Wooster. He can be reached at chatfield.1@osu.edu. Erik Draper is commercial horticulture educator and director of The Ohio State University Geauga County Extension office in Burton. He can be reached at draper.15@osu.edu.