The Aril Society Checklist

 by Tom Waters

When I'm not writing blog posts, one of my many other iris-related activities is serving as checklist editor for the Aril Society International. I've just completed the 2023 update of the checklist, which is available on the ASI website. It occurred to me that there are probably many people who are not aware that the ASI maintains a checklist of aril and arilbred irises, nor aware of what it offers beyond other references. So I thought I would use this blog post to have a look at the checklist and why it is important.

When the Aril Society International was formed in the 1950s, there were no standardized definitions for the various types of aril and arilbred irises. Irises with oncocyclus or Regelia ancestry were registered with the American Iris Society under a bewildering range of classification codes. One of the first tasks of the new society was to sort through all the various registrations and establish specific categories for them. A persistent problem in the early years was that irises of 1/8, 1/16, or even less aril ancestry were being given awards as arilbreds despite being indistinguishable from TBs. The society addressed this by requiring irises to be 1/4 aril or more to be considered as arilbreds. Subsequently, there were two separate award systems created: one for arilbreds of 1/4 to 1/2 aril content, and another for irises of 1/2 aril content or more.

'Loudmouth' (Rich, 1970) won the
C. G. White Award as an OB (1/2 aril)
but is now an OB- (less than 1/2) 
because of a change in definition.

The checklist was critical for establishing which irises met the various award criteria. The editor would take the registration data, do pedigree research, consider an iris's appearance, breeding behavior, and any chromosome counts that had been done, and then assign it to the appropriate category. In days before the internet, the ASI checklist was the only source of this classification information, because it was impractical to reprint the American Iris Society checklists to give updated classifications for arilbreds. The classifications and definitions used by the Aril Society have changed several times over the years, and the checklist is the only authoritative reference on how definition changes have affected the classification of each arilbred iris. Applying the current definitions, which involve estimating the chromosome makeup of each cultivar, is not a trivial matter in some cases.

Here are some of the things you will find in the ASI checklist that may not be presented accurately (or at all) in other sources:

Classification Information. Each iris listed, even historic irises registered long ago under other definitions, are assigned to the current ASI classification, to the extent possible given the existing information. This is of particular value to show classification committees in regions where arils and arilbreds are likely to be exhibited. It is especially important for irises that were once considered arilbreds, but no longer meet the definitions of that class.

Height Categories. In 2018, the ASI established definitions for two height categories for smaller arilbreds: arilbred dwarf (ABD) and arilbred median (ABM). These are included in the current edition of the AIS Judges' Handbook. The checklist gives the correct height category for each arilbred listed.

Chromosome Configuration. Aril and arilbred irises may include chromosome sets from oncocyclus, Regelia, tall bearded, and dwarf bearded species. Which chromosome sets are present in a given iris is of considerable interest to hybridizers, as it affects fertility and helps the hybridizer properly classify any resulting seedlings. The checklist provides the most likely chromosome configuration for most irises listed, along with an actual chromosome count where one has been reported.

Fertility Observations. When an iris is known to have produced offspring as a seed parent or pollen parent, this is noted in the checklist.

Is this 'Bronze Beauty',
'Hoogiana Bronze Beauty',
Iris hoogiana 'Bronze Beauty',
'Bronze Beauty Van Tubergen',
or 'Antiope'? Answer: yes.

Irises Not Eligible for Awards as Arilbreds. An appendix to the checklist provides a thorough listing
of irises that do not qualify as arilbreds for various reasons: never having been registered, having been registered in a non-arilbred class, or having been disqualified as definitions became more strict.

Nonregistered Aril Hybrids. A substantial number of aril hybrids have been introduced, particularly through the firm of Van Tubergen in the Netherlands, that were never registered with the American Iris Society. Some were registered with the Dutch registration authority for bulb irises, while others were simply not registered at all. The checklist includes these in an appendix, along with photographs and other information.

Even today, where so much information seems just clicks away on the internet, the ASI checklist fills an important role in providing authoritative information that is not reliably available elsewhere. It is an important resource for judges, show officials, and hybridizers. Anyone with an interest in aril and arilbred irises should become familiar with what the checklist has to offer.

Proportion, Proportion, Proportion

 by Tom Waters

There is no excellent beauty that hath not some strangeness in the proportion.

                —Francis Bacon

It seems like devotees of the dwarf and median irises, myself included, are always talking about proportion. All the parts of the stalk, we are told, must be in proportion: the height and width of the flowers, the height and thickness of the stalk, even the leaves. Indeed, the American Iris Society’s Handbook for Judges and Show Officials gives measurements and ratios to define proper proportion for each class.

I’d like to raise a philosophical issue about proportion, and how it relates to two iris classes in particular, the border bearded (BB) and miniature dwarf bearded (MDB). These two classes face a similar problem: most BBs are produced by crossing tall beardeds (TBs), and most MDBs are produced by crossing standard dwarf beardeds (SDBs). Since the genetic background of these classes comes mostly from a different, taller class, it is not unusual to find flowers that are large, even when the height of the stem is short. Purists are very bothered by this situation, but short irises with large flowers seem to be popular with iris lovers and even judges. Are the many people who enjoy large-flowered BBs and MDBs just wrong? Should they know better?

The philosophical issue is this: is “good proportion” objective? Is there some numerical ratio of stem, flower, and foliage that is aesthetically optimal? Or is it just in the eye of the beholder? If it is just a personal, subjective preference, then the admonitions in the Judges' Handbook start to seem a bit arrogant and elitist. The classic example of a subjective judgment becoming judging gospel is the case of haft marks. In the mid-20th century, haft markings were the “fault” that everyone seemed obsessed with in TB irises. Yet, what if I think haft marks are interesting or pretty? Is this any different than preferring yellow to blue, or preferring plicatas to selfs? The condemnation of haft marks reflects the struggles of hybridizers. In those early years, it was very difficult to breed a true, clean, self-colored iris. Haft marks seemed to always turn up and distract from the desired purity. So the frustration felt by hybridizers was transformed into an esthetic standard that was promoted as something objective and universal. Once clean selfs were achieved, then people could start to enjoy haft marks for being “something different”!

Many, many “rules” that are enshrined in the Judges' Handbook are relics of the personal goals and frustrations of earlier generations of hybridizers, even though they are presented as objective aesthetic truths. I think proportion is one of those things. I say this despite the fact that I, personally, dislike large-flowered BBs and MDBs. If a BB blooms in my garden with TB-sized blooms and thick, coarse stalks, it does not stay here another year, no matter how pretty the color or form. However, in all honesty, I have to describe this as a personal preference.

Allium karataviense

If there were some objective, universally valid, proportion of bloom to stalk that looks best to everyone, then we would expect it to apply to all kinds of plants. But in fact, we enjoy flowers with all different ratios of bloom size to stem height, without thinking twice about it. Consider two alliums I grow: A. karataviense produces enormous globular flower heads right at ground level. I enjoy it immensely. A. caeruleum produces small, airy blue flower heads on tall slender stalks. I enjoy it also. These two could not be more different. And neither has the proportion of a “good” bearded iris. In fact, I think an iris proportioned like either of the alliums would inspire revulsion in a typical iris judge.

Allium caeruleum

It may seem like I am now arguing for a free-for-all approach to proportion. If it is all subjective, why should we worry about a BB with TB-sized flowers or an MDB whose bloom is twice as wide as the height of the entire stem? Perhaps judges should focus on more objective things, like plant vigor and bud count, and let people enjoy different proportions, just as we enjoy different colors?

No, that is not the approach I favor, although I think the argument should be made from time to time to provoke thought and debate. I believe there is a good reason for harping on proportion in the dwarf and median irises, but I don’t think it has anything to do with some objective, universal standard of beauty.

'Solar Sunrise' (Black, 2019),
a BB whose proportion I like.

What then? If small-flowered BBs and MDBs are not objectively superior to large-flowered ones, why should we care at all? I think the answer lies in something else: class identity. Consider this: although they fall in the same height range, miniature tall bearded (MTBs) are “supposed” to have smaller flowers and more slender stems than BBs. If one proportion is more attractive, shouldn’t all classes aspire to that same proportion?

To most median aficionados, the answer is obvious: each class has its own aesthetic ideal. We like the fact that BBs look different from MTBs. They are like two different styles of music. In our minds, we may have a picture of the ideal, the prototype, as it were, for each class. It is these mental prototypes that give each class its identity, its center of gravity in the great sea of diversity that hybridizers have produced for us.

So I think what we are complaining about when we complain about out-of-proportion BBs or MDBs is the erosion of the identity of the class, the weakening of the mental prototype. The reason I have singled out BBs and MDBs is that the irises in these classes are mostly “spill-overs” from TBs and SDBs, respectively. There is a relentless pull on these classes to merge together with the larger classes that give rise to them. If a BB is just a TB that is short, why not call it a TB?

'Icon' (Keppel, 2008)
an MDB whose proportion I like.

Some have sought to strengthen the identity of these classes through breeding. Lynn Markham’s BBs
were produced intentionally to reinforce the distinct identity of the class. Ben Hager used a similar strategy to reinforce the identity of the MDB class. These were valiant efforts, but they were not sufficient to turn the tide. So many people are crossing TBs that the “accidental” BBs that emerge from TB crosses far outnumber the “intentional” BBs that are produced by the small number of breeders who are interested in the class as an end in itself. Exactly the same is true of the MDB class.

I wish I could end on some profound revelation or recipe for solving the conundrum of these classes, but I don’t think there is one. What it comes down to is simply this: do we (the entire iris-loving public, hybridizers, and judges) care enough about the identity of these classes to insist on maintaining their integrity? Perhaps we don’t. It’s not obvious that we “should”, after all. If we like the irises we’re growing, even when they depart from that mental prototype, maybe that is fine. Collective opinion is not something that can be easily predicted or controlled. It just is what it is.

But if nothing else, perhaps we can shift the language of the conversation a little. Instead of talking about “good” or “bad” proportion, perhaps we can talk instead of class identity. That seems more accurate and to the point.

 

Understanding the Historic Dwarf Bearded (DB) Class

By Tom Waters

Before 1958, the now familiar American Iris Society (AIS) horticultural classes for bearded irises did not exist. Certainly there were bearded irises of different sizes, but the precisely defined “dwarf,” “median,” and “tall” bearded classes were still gradually taking shape as a way to describing the diversity of the bearded irises in nature and in the garden. Today, we use “median” to refer to all the bearded irises except miniature dwarfs and tall bearded. 

Consequently, care must be taken in assessing how the earlier bearded irises were categorized. This post will look at just one such category, the dwarf bearded irises, abbreviated DB prior to 1958.

DB 'Artoviolacea' (Todaro, 1856)
probably a natural hybrid
of I. lutescens and I. pumila
Photo: El Hutchison

In the early 1900s, botanists were aware of a number of dwarf bearded species, notably Iris pumila, I. lutescens (then mostly known by the name I. chamaeiris), I. aphylla, I. reichenbachii, and others. Gardeners in western Europe and the United States were also familiar with garden cultivars of dwarf bearded irises. These were almost exclusively forms of I. lutescens or hybrids between I. lutescens and other dwarf species. I. lutescens is native to the Mediterranean regions of France, Italy, and Spain. Other dwarf Iris species are native to Eastern Europe, and thus I. lutescens was more accessible to early commercial nurseries in France, England, Germany, and the Netherlands.

There was little concern about establishing a precise definition for the DB category. Dwarf cultivars being grown were easy to distinguish from tall beardeds (TBs), and that was really all that mattered. Crossing dwarfs with talls produced intermediates,  another widely used term. The intermediate beardeds (IBs) were a pretty obvious group of hybrids and easily distinguished from both dwarfs and talls. Keep in mind that this was long before separate awards were established for different irises. Terms like dwarf, intermediate, and tall were helpful descriptions for irises rather than a specific horticultural class that needed to be assigned unambiguously.

DB 'Bride' (Caparne, 1901)
probably pure I. lutescens,
6 to 8 inches in the author's garden
photo: Tom Waters

The AIS checklists of the 1920s defined dwarf bearded irises by listing some familiar dwarf species, and noting that the term included hybrids between these species. The 1939 checklist added some precision by stating that dwarf irises were up to 17 inches in height. It was not clear whether ancestry from dwarf species or height was to be decisive; it was just taken for granted that hybrids among the dwarf species and cultivars would fall into the expected height range.

What were these early dwarfs like? Like the species I. lutescens that dominated their ancestry, the early dwarfs were mostly between 6 and 12 inches in height, almost never branched, bearing one or two terminal buds. Colors ranged from yellow, cream, and white, to blue, violet, and purple. Most had self or bitone color patterns. The spot pattern from I. pumila, so familiar to us in modern dwarfs, was seen only occasionally. All blooms were tailored, and the plants bloomed before the intermediates and talls. Although I. lutescens in the wild often shows interesting markings, patterns, and blended colors, these were not common among garden varieties. Perhaps this reflects the preference for clear, smooth colors that persisted among iris fanciers until the later decades of the 20th century.

DB 'Path of Gold' (Hodson, 1941),
a child of 'Bride' and
probably pure I. lutescens, is
10-12 inches in the author's garden.
Photo: TomWaters

Hybridizing with dwarf irises took a back seat to TB hybridizing until the 1940s and 1950s. William J. Caparne of England produced many dwarfs around 1900, as did the German firm of Goos and Koenemann. A number of American hybridizers subsequently worked with dwarfs, most notably Hans and Jacob Sass of Nebraska.

As hybridizing progressed, it became clear that complicated hybrids might not always fall into one of the intuitive categories being employed. In 1948, the AIS adopted a new set of classes defined by L. F. Randolph. Randolph rejected height as a decisive factor, and offered instead a rather vague notion that advanced generation hybrids that had "most of the characteristics of typical dwarf bearded irises" (he had in mind things like season of bloom, short foliage and stalk, lack of branching, etc.) would be considered DBs.

This way of thinking about the class was soon pushed to the breaking point. Hybridizers had begun importing and working with different species, outside the familiar I. lutescens and its hybrids. Robert Schreiner had imported seeds of the tiny cold-hardy species I. pumila from eastern Europe, and this exciting new species gradually spread among dwarf hybridizers. Paul Cook introduced the first hybrids between I. pumila and TBs in 1951: 'Baria', 'Fairy Flax', and 'Green Spot'. Although the term had not yet been invented, these were the prototype of what would become the modern classification of standard dwarfs. Did these new irises have "most of the characteristics" of dwarfs? At a mere 10 inches, they were less than 18 inches tall, to be sure, but did having a TB parent make them intermediates? They were sometimes branched, not a characteristic of "typical" DBs of the time.

DB 'Sapphire Night' (Nicholls, 1935),
perhaps a hybrid involving
 I. lutescens and I. aphylla,
12-14 inches in the author's garden.
Photo: Tom Waters

Cook registered his new hybrids as IBs, but to many iris fanciers that just seemed wrong. In 1954, AIS introduced a new height-based classification, where any bearded iris 15 inches tall or less was a DB, regardless of ancestry or other characteristics. This caused a schism with many dwarf enthusiasts.

Eventually the matter was settled by splitting the DB class in two: a miniature dwarf bearded (MDB) class with an upper height limit of 10 inches (reduced to 8 inches in 1976), and a standard dwarf bearded (SDB) class from 10 to 15 inches. The MDBs were the province of the Dwarf Iris Society, whereas the SDBs were regarded as medians and promoted by the Median Iris Society.

The effects of Cook's new hybrids were not limited to the classification system. Excited by the developments, dwarf hybridizers scrambled to use I. pumila and the new SDBs in their breeding. The 1950s was a transition decade: it began with nearly all DBs being cultivars or hybrids of I. lutescens, and ended with nearly all MDBs and SDBs being hybrids of I. pumila and TBs in varied proportions. The influx of TB genes brought plicatas, pinks, and ruffled blooms into the dwarf iris world; I. pumila brought dramatic and varied spot patterns.

What does this all mean for the collector of historic dwarf bearded irises? First, it is essential to understand that the DB class does not correspond to any single modern class. It spans the height range of both MDB and SDB classes, even extending into the IB class in some instances. In principle, every historic DB could be assigned to a modern class on the basis of height. However, height was not recorded in early registration data; so such determinations would require catalog descriptions or garden observations. The Median Iris Society attempted to make such reassignments for the IB, MTB, and BB classes, although I do not know of any similar undertaking having been made for the MDBs and SDBs.

Even if we were able to sort historic DBs into modern classes based on height, that would not capture the essential nature of the old category. It represents irises of different ancestry and genetic characteristics than the modern classes. The 8-inch height boundary is even less meaningful for the old DBs than it is for their modern successors. I. lutescens and its hybrids span this boundary, and there is seldom any meaningful difference between a 7-inch and a 10-inch DB.

I think the best advice for modern growers interested in collecting historic dwarfs is to approach them on their own terms: viewing the DB category in its own right with context that differs from modern hybrids. Starting from that perspective, one can then notice some similarities and comparisons that might be made: A DB that is a I. lutescens/pumila hybrid, for example, might resemble an MDB that is an SDB/I. pumila hybrid.

The historic DBs are harder to come by than modern cuiltivars, but it is worthwhile to acquire and grow a few. Not only will you be helping to preserve a window into iris history, you will also get to enjoy a type of iris that really has no modern counterpart.

What is a Dwarf Bearded Iris?

…and why are dwarf lovers so persistent?

 Tom Waters

'Icon' (Keppel, 2008)

In the beginning, there were no class definitions. The meaning of the term “dwarf bearded iris” was taken for granted, as all the ones being grown in gardens were similar in appearance and distinct from their taller relatives.  If you were botanically inclined, you could turn to a reference like W. R. Dykes’s The Genus Iris to get a list of dwarf bearded species, and safely assume that your garden dwarfs were hybrids or forms of those species.

The 1939 AIS Checklist attempted to be somewhat more helpful by giving a height range in addition to the list of species, setting the boundary between dwarfs and intermediates (which were stated to be hybrids between dwarf and tall bearded irises) at 17 inches. This doesn’t make sense, though, if it is taken as a definition, rather than just helpful descriptive information. What if two of those dwarfs species were crossed and produced a hybrid over the limit? Or what if a dwarf and tall were crossed and produced a hybrid under the limit? Giving both a definition in terms of ancestral species and a definition in terms of height is inviting contradiction unless it is clear whether ancestry trumps height or vice versa.

Perhaps in recognition of this, the AIS adopted a new classification in 1947, based decisively on ancestry. A hybrid involving only dwarf species would always be a dwarf; a hybrid involving only tall species would always be a tall. A hybrid involving both dwarfs and talls would usually be intermediate, but might be deemed either dwarf or tall if that was the group it most resembled. Although this last provision was strangely vague, the definition at least allowed hybridizers to cross dwarfs amongst themselves and register the progeny as dwarfs, without worry about a height limit or other factors.

This classification system was introduced at the same time as Walter Welch was organizing the Dwarf Iris Society (then called the Dwarf Iris Club) and stirring up interest in dwarf hybridizing, so there may have been some impetus to clarify definitions for this reason. Although dwarfs had been widely grown in both Europe and North America for as long as tall beardeds, they had not historically received a great deal of attention. Gardeners took them for granted, and although new hybrids were introduced from time to time, there were no hybridizers who focused on them exclusively or had planned breeding programs solely to produce new dwarfs. Welch turned that around, first by organizing a program of round robins, whereby enthusiasts (many of them recruited from gardening clubs and publications, not just iris societies) could discuss dwarf irises by mail, and then by creating the Dwarf Iris Club in 1950. I believe this was the first specialist iris society devoted to a particular type of iris. With the blessing of the AIS, the Dwarf Iris Club even trained and appointed its own judges, just for judging dwarfs!

In 1951, something happened that put the class definition under unprecedented strain. Paul Cook (a friend and correspondent of Walter Welch) introduced the first three irises of the type we now know as standard dwarf bearded (SDBs), from crossing the tiny dwarf species Iris pumila with tall beardeds. As a dwarf x tall cross, a strong case could be made that these new irises were intermediates, and indeed that is how they were registered at the time. But they were no taller than many of the dwarfs being grown at the time, so this might seem a little inconsistent. Welch and the DIS focused attention on the presence of a small branch in most SDBs, asserting that a branch was disqualifying for being considered a dwarf. Oddly, the list of dwarf species that AIS had been printing and reprinting for many years included amongst the dwarfs Iris aphylla, which is copiously branched.

The 1954 classification made
the dwarf people grumpy

Recognizing that the future might hold even more examples of such “problem children” from newfangled hybridizing experiments, the AIS suddenly reversed itself in 1954, offering a classification based entirely on height, with ancestry deemed irrelevant. This makes sense in a world where parentages have become complex or uncertain. Height is something that can be established with a ruler. Now the boundary between dwarfs and intermediates was set at a rigid 15 inches, regardless of what species the plants had come from or what characteristics they had. Welch and the DIS refused to accept this definition, appalled at the thought of 15-inch branched “intermediates” masquerading as dwarfs! Welch could be an opinionated and difficult person under the best of circumstances, and now he and his supporters had a righteous cause for contention. This caused a rift between the AIS and the DIS whose repercussions are still playing out today. From 1955 until 1973, the DIS had its own awards system, issuing the Welch Award in competition with AIS’s Caparne Award, despite the fact that it tended to be the same irises winning both awards.

Other classification issues were percolating at this time as well. There were movements afoot to recognize the so-called “table irises” and “border irises” as separate from both TBs and IBs. A committee was put together to study all these issues and propose a solution. In 1958, the AIS adopted a classification that has remained in place (with minor modifications) to this day. The dwarfs were separated by height into miniature dwarfs and standard dwarfs, with the dividing line being 10 inches. The border bearded class was created for short TBs, and the miniature tall bearded class was created for the table irises. The DIS had no interest in any of these new classes, not even the SDBs, and so the Median Iris Society was formed with the mission of promoting the five new classes between MDB and TB. A peculiar quirk of this development is that standard dwarfs are considered medians, not dwarfs, in apparent contradiction with their name.

'Alpine Lake' (Willott, 1980)
a classic MDB from SDB x pumila breeding

The 1960s and 1970s were perhaps the most exciting time in the history of dwarf iris development. Although the SDBs themselves were deemed too large to be considered true dwarfs, they had an enormous impact on breeding. Dwarf enthusiasts crossed the SDBs back to I. pumila, producing many charming hybrids, earlier blooming than the SDBs and quite distinctive in appearance, with ¾ of their genes coming from the dainty I. pumila. This became the standard cross to produce MDBs. The class was rounded out by selections of pure pumila ancestry, as well as hybrids from pure SDB breeding that happened to be small enough to fit the definition of the MDB class. These “runt SDBs” did not always meet with the approval of the dwarf purists, although there are a number of fine irises in this category. Indeed, in recent decades these MDBs from pure SDB breeding have come to quite dominate the class, in terms of sheer numbers as well as awards.

'Little Drummer Boy' (Willott, 1997),
an MDB from pure pumila breeding

In light of this history, one can understand why the DIS has remained rather protective of the little irises under its charge, and reluctant to muddle the boundary between the dwarf MDBs and the median SDBs; the dividing line between the classes was reduced to 8 inches in 1976, in part to protect the MDB class from SDB interlopers. It also explains the misgivings of many DIS members about merging with MIS, which has been suggested on a number of occasions. Any of the median classes might seem to have more cause to have its own society, given that they all have more new irises introduced each year than does the MDB class. Yet our history has set us apart, and perhaps it is the very fragility of the class in the face of the much larger (in numbers as well as stature!) median classes that inspires a certain connoisseur’s devotion amongst us.

'Pearly Whites' (Black, 2014),
an MDB from pure SDB breeding

In 2018, the DIS seemed on the brink of demise, with the president and vice president resigning, and the officers voting to merge with MIS. Rather miraculously, this was reversed in 2019, with a grass-roots rallying of the troops under the enthusiastic leadership of Charlie Carver, historic iris conservation advocate and devotee of MDBs. We now once again have a functioning society with a full slate of officers and a content-rich newsletter in final preparation for publication early this year. If you love dwarf irises and would like to be part of this renaissance, the DIS would love to hear from you!

Dwarfs for Every Garden

by Tom Waters

The dwarf bearded irises (those classified as miniature dwarf bearded, or MDB) are a charming addition to any garden. With blooms held eight inches (20 cm) or less from the ground, they are the daintiest of all the bearded irises. They are also the earliest to bloom. In my garden, the first ones open a full two months before tall bearded season.

Almost all MDBs grown today fall into one of three categories. All three groups owe their existence to the eastern European species Iris pumila, which came to be used by American hybridizers in the 1940s.

'Liitle Drummer Boy'

The first category is Iris pumila itself. This tiny species is seldom more than 4 or 5 inches (10-12 cm) in height, with just one bloom per stem. (Actually, the stem is often almost nonexistent, most of the height being in the perianth tube formed by the flower parts themselves.) It comes in a range of colors from white and yellow to blue, violet, and purple, usually with a darker colored spot on the falls. There are a number of cultivars produced by hybridizers or selected from wild forms for their garden value. Some of my favorites are 'Little Drummer Boy' (Willott, 1997), 'Hobbit' (Miller, 2004), and 'Royal Wonder' (Coleman, 2013).

'Hobbit'

'Royal Wonder'

The next two categories came about as a consequence of the creation of the first standard dwarf bearded (SDB) irises in the 1950s. As I discussed in an earlier blog post, the SDBs were the result of crossing Iris pumila with tall bearded irises (TBs). The SDBs averaged about 12 inches (30 cm) in height and would typically have 2 or 3 buds. They are regarded as medians, not as true dwarfs, because of their larger size and occasional branch, something not seen in traditional dwarf irises.

'Alpine Lake'

Shortly after the SDBs appeared, hybridizers crossed them back to Iris pumila to produce irises of truly dwarf stature, but with a little something extra from their TB ancestry: plicata pattern, for example, or wider petals and more flaring form. These were the most common type of MDB in the 1960s, '70s, and '80s. 'Knick-Knack' (Greenlee, 1961), 'Zipper' (Sindt, 1979), and 'Alpine Lake' (Willott, 1981) are good examples of this type.

The third category came about from SDB breeding in an even more direct way. Sometimes crossing two SDBs produces an iris smaller than average. These small ones, if they are 8 inches or less in height, belong in the MDB class, since the definition for that class is based on height, not ancestry. Because so much work has been done to improve the SDB class over many decades, these are often the most "developed" dwarfs in terms of form and variety of color and pattern. Popular examples of this type are 'Dollop of Cream' (Black, 2006), 'Icon' (Keppel, 2008), and 'Beetlejuice' (Black, 2013).

'Dollop of Cream'

'Icon'

Generally speaking, the greater the amount of Iris pumila in a dwarf's makeup, the smaller, earlier, and more adapted to cold winters it will be. Those with less Iris pumila will have larger flowers with greater width and ruffling, a greater range of color patterns, and perform better in warm-winter areas.

There are no official designations for these categories, although hybridizers sometimes identify them by the number of chromosomes: Iris pumila has 32, the SDBs and their small MDB progeny have 40, and the SDB x pumila hybrids have 36.

How can you tell which of these categories and MDB belongs to? Alas, the only way to be sure is to look at the parentage on the Iris Encyclopedia or other resource. In most cases, this will lead you back either to SDBs or to Iris pumila, or else the parentage will be an SDB x pumila cross. If this sort of research interests you, my list of pure Iris pumila cultivars may help make sense of things.

I love dwarfs in all their variety, and happily live in a locale where all kinds grow well. Do you grow dwarfs in your own garden? Which kinds are your favorite?

Classifying Aril and Arilbred Irises

by Tom Waters

If you're even a little interested in arils and arilbreds, you will have noticed that there is a rather bewildering array of terms used to describe them in catalogs, in iris society publications, and in general use among iris growers. In today's post, I hope to help make sense of it all.

The Big Distinction

The most important distinction of all is that between arils and arilbreds. By today's definition, an aril is a species from the oncocyclus or Regelia sections, or a hybrid derived only from these two groups of species. In contrast, an arilbred is a hybrid derived from both arils and ordinary bearded irises (whether tall bearded, median, or dwarf).

Although this seems pretty easy, and these definitions have been official for more than half a century, one still often hears people casually refer to both arils and arilbreds as "arils". This creates a truly unfortunate confusion, especially since arilbreds differ from arils in both appearance and cultural requirements. To emphasize the distinction, you will sometimes hear people speak of "pure arils" to clarify that they are not talking about arilbreds.

A Closer Look at Arils

Aril hybrids are hybrids whose ancestry is only oncocyclus, Regelia, or both. A hybrid with only oncocyclus ancestry is an oncocyclus hybrid (OH), one with only Regelia ancestry is a Regelia hybrid (RH). Simple enough. But there are two terms in use for hybrids that are a mixture of oncocyclus and Regelia: regeliocyclus (RC) and oncogelia (OG). Originally, these terms indicated whether the cross used to produce the hybrids was Regelia x oncocylcus or oncocyclus x Regelia, but that turned out to be an unhelpful distinction. The appearance of the flowers doesn't depend on which direction the cross is made, and once you have advance-generation hybrids, the distinction is impossible to maintain. Today, we use RC to refer to aril hybrids where the Regelia influence is predominant (these are typically 1/2 Regelia or more by ancestry, but it really depends on the appearance of the flower, not the details of the pedigree). OG, naturally, refers to a hybrid where the oncocyclus influence is predominant.

Iris acutiloba lineolata, an oncocyclus

Iris stolonifera, a Regelia

A Closer Look at Arilbreds

Long ago, people used the word "arilbred" to refer to any iris with both aril and bearded ancestry, regardless of how little aril ancestry or aril flower characteristics it had. Today we know that inheritance is through chromosome sets, and a set of chromosomes is usually either passed on to a hybrid as a complete set or not at all. So many older "arilbreds" that were 1/8 or 1/16 aril by ancestry really had no aril content at all!

One of the first initiatives of the Aril Society International after it was formed in the late 1950s was to restrict the definition of arilbreds to irises with significant aril ancestry and significant aril appearance. Today, to be classified as an arilbred, an iris must be at least 1/4 aril by chromosome complement and the flower must show at least two aril characteristics, such as signal or veining. This definition helps protect the distinctiveness of arilbreds as a class.

Another initiative of the Aril Society was to encourage hybridizers to work with arilbreds that had more aril content and appearance. A separate category was created for arilbreds that are at least 1/2 aril, and these are eligible for a special award, the Clarence G. White Medal. Those less than 1/2 aril are eligible for the William Mohr Medal instead. Unfortunately, there is no simple terminology to distinguish these two categories; you just have to say "less than 1/2 aril" and "1/2 aril or more".

One peculiarity of this division is that aril hybrids (pure arils) are also eligible for the C. G. White Medal, because not enough of these are produced or widely grown to merit their own system of awards. I think this has contributed in a small way to the confusion between arils and arilbreds - for a number of years, the American Iris Society used the abbreviation "AR" for both arils and arilbreds eligible for the C. G. White Medal, and "AB" for arilbreds eligible for the William Mohr Medal.

Nine Types of Arilbreds? Yes, Really

Although for awards purposes, the American Iris Society sorts all arilbreds into only two classes (less than 1/2 aril and 1/2 or more aril), the Aril Society uses a more detailed system of categories that tracks not only the amount of aril content, but also the type of aril content (oncocyclus, Regelia, or both).

An arilbred with only oncocyclus and bearded ancestry is an oncobred (OB). One with only Regelia and bearded ancestry is a regeliabred (RB). If both oncocyclus and Regelia ancestry are present, it is an oncogeliabred (OGB). This is by far the largest category.

If the arilbred has less than 1/2 aril content, it is marked with a "-" sign. If more than 1/2, with a "+" sign. If it has 1/2 aril content exactly, neither a "-" or "+" is used.

So all together that makes nine types of arilbred: OB-, OB, OB+, OGB-, OGB, OGB+, RB-, RB, and RB+.

'Bhutan' (Tasco, 2010), an OGB

'Jeweled Veil' (Rich, 1978), an OGB+

A point to note is that since 1990, the amount of aril content is based on chromosome sets, not parentage (which is why the word "content" is used rather than "ancestry"). Although the distinction between chromosome content and ancestry often makes no difference, there are times when it does. 'Loudmouth' (Rich, 1970), for example, came from a cross of an oncocyclus with an SDB. Thus it is 1/2 aril by parentage. However, the oncocyclus parent was a diploid, providing only one set of aril chromosomes, whereas the tetraploid SDB parent provided two sets of bearded chromosomes, making 'Loudmouth' only 1/3 aril by chromosome content. It won the C. G. White award under the old parentage system, but today it is classified as OB-, and would not be eligible for that award.

'Loudmouth', an OB-

Despite all this attention to detail regarding the aril ancestry of arilbreds, no distinctions at all are made regarding the type of bearded ancestry, whether TB, dwarf, or median. Sometimes smaller arilbreds with dwarf or median ancestry are called "arilbred medians", "aril medians", or other similar terms, but these are not official categories.

Finally, here is a chart that tries to make sense of this all:

I hope this post has shed some light on a rather complicated subject. Do you find these categories helpful when choosing and growing arils and arilbreds?

Standard Dwarf Bearded Irises: A Success Story

by Tom Waters

'Abuzz With Charm' (Coleman, 2013)

Standard dwarf bearded irises (SDBs) are defined as bearded irises between 20 cm (8 inches) and 41 cm (16 inches) in height. But behind that simple definition is an exciting story of the creation and development of a family of wonderful garden plants unknown in nature, beginning with two curious hybridizers collaborating on an experiment and culminating in what would become an enormously successful class of irises, second in popularity only to the tall beardeds.

The story begins in the 1930s with Robert Schreiner seeking out seeds of the dwarf bearded species Iris pumila, native to eastern Europe. There were already dwarf irises grown in gardens at that time, nearly all of them derived from Iris lutescens, a species native to the western Mediterranean: Italy and southern France. There was not much potential in breeding these dwarfs, however. The color range was limited (yellow, violet, and occasionally off-white), and attempts to add more variety by crossing them with tall bearded irises produced only sterile intermediates, a dead end as far as improving the dwarfs was concerned.

Iris pumila

Iris pumila offered the prospect of something new for dwarf breeding. Although not grown in western Europe or North America, it was known to iris specialists. It was one of the iris species originally listed by Linnaeus, and was described in W. R. Dykes's The Genus Iris and other sources. It is a truly diminutive iris, virtually stemless, with the tip of the blooms often only 10 or 15 cm above the ground. Its range of colors is delightful: yellow, cream, pure white, violet, purple, and blue, almost always with a darker spot on the falls. Instead of just lamenting its unavailability from commercial sources, Schreiner initiated communication with plant enthusiasts in eastern Europe, and was eventually able to import some seeds of this promising species.

By the 1940s, Iris pumila was being grown by a small handful of iris hybridizers in the USA. Two of them, Paul Cook in Indiana and Geddes Douglas in Tennessee, decided to exchange pollen. Iris pumila was blooming in Indiana around the same time as the tall beardeds were blooming in Tennessee. The results of these crosses delighted them both. The stems grew about 30 cm in height, only slightly larger than the garden dwarfs of the time. There were two buds at the top of the stem, and often a third on a short branch. The flower form was perky and modern by the standards of the time, and the colors were bright and varied wonderfully. And, most extraordinarily, these new hybrids were fully fertile and could be bred with one another for as many generations as the hybridizer desired. These were the first of a new type of iris, now called SDBs. Paul Cook introduced the first three to the world in 1951: the clear yellow 'Baria', blue 'Fairy Flax', and white and green 'Green Spot', which achieved an enduring popularity among iris enthusiasts.

'Green Spot' (Cook, 1951)
photo: Barbara-Jean Jackson

The creation of these new hybrids soon caused controversy. Were they dwarfs or were they intermediates? Many dwarf enthusiasts insisted on the latter view. Iris pumila was a dwarf, after all, and crossing dwarfs with TBs was the classic recipe for intermediates. Furthermore, they argued, no true dwarf iris could have a branched stalk, which SDBs often did. Others, however, noticed that these new irises were much closer in size and general appearance to the dwarfs than to the intermediates, and preferred to just stretch the definition of "dwarf" a little bit to accommodate the new hybrids. Geddes Douglas thought they should be in a class by themselves, neither dwarf nor intermediate, and proposed calling them "lilliputs".

By the mid-1950s, those who preferred grouping the new irises with the dwarfs had prevailed. The AIS adopted a classification where any bearded iris up to 16 inches in height was considered a dwarf. The Dwarf Iris Society refused to accept this however, and the result was a schism between the two groups, with the DIS having its own judging standards and its own system of awards. This state of affairs was untenable, and by 1958, it was clear that the classification problem needed serious rethinking.

'Rain Dance' (B. Jones, 1979)

The final outcome was abandoning the simple division of dwarf, intermediate, and tall, and replacing it with four "median" classes in between the dwarfs and the talls. The intermediate class remained, but now there would also be a new class for "lilliputs" and two more classes in the intermediate height range, one for small TBs (border bearded) and one for the dainty diploid "table irises" (miniature tall bearded).

So the new pumila/TB hybrids now had their own class, but what should they be called? Douglas's name "lilliput" was deemed a bit too fanciful. The final decision was to call them "standard dwarf bearded" and refer to the smaller true dwarfs as "miniature dwarf bearded". The Dwarf Iris Society would continue to promote only the MDBs, while a new organization, the Median Iris Society, was created to promote the four median classes: SDB, IB, MTB, and BB. The result is a slightly perplexing situation where the SDBs, although having the word "dwarf" as part of their name, are technically medians, not dwarfs.

This brand new type of iris shook up the conventional thinking of the time, but the result was much better than if they had been forced into either the dwarf or intermediate categories. Having their own class and their own awards gave great encouragement to breeders striving to improve them. And the improvements came rapidly. Breeders like Bee Warburton and Bennett Jones were at work from the beginning, scarcely behind Cook and Douglas in producing new SDBs. Before long, most hybridizers were no longer crossing Iris pumila with TBs to produce new SDBs. It was easier to simply cross the existing SDBs with each other, and the results were usually better too.

The influence of the SDBs extended beyond their own class. Today, most IBs come from crossing SDBs with TBs, and most MDBs derive from SDBs as well.

SDB breeding produced some extraordinary surprises. It was originally thought that some of the recessive colors and patterns, such as pink and plicata, could only appear in TBs. But it did not take long before they began showing up in SDBs as well. Today's SDBs have virtually all the colors and patterns seen in TBs, as well as the "spot pattern" inherited from Iris pumila. I think it is fair to say they are the most varied class of irises in existence.

'Chubby Cheeks' (Black, 1985)
photo: Mid-America Garden

In the nearly 65 years since the first SDBs were introduced, there has been a steady improvement in form and substance. Bennett Jones's creamy white 'Cotton Blossom' was hailed as an early improvement in form, with wide round petals and light ruffling. But the greatest breakthrough was Paul Black's 'Chubby Cheeks' in 1985. A prodigious parent for decades, this iris and its descendants set a new standard of form for the entire class.

SDBs are deservedly popular, and not only for their varied colors and appealing flower form. They bloom about a month earlier than TBs in most climates, greatly extending the iris season. Furthermore, their size makes them more versatile in garden design than their larger cousins. They can be tucked in next to a doorway, along a path, or even used in small "postage stamp" backyards where TBs would be out of scale. It's hard to imagine the iris world without them.

And we owe their very existence too a few creative souls whose curiosity prompted them to step outside the status quo and try something different. Who can say where the next great iris success story will come from?