by Randy Clark

I was sitting here the other day wondering what I should write about for the next newsletter article with not much success. My brain was smoking like the wheels of a really fast race car when I just said to myself "ah, just do something fun". Well, fun is relative, but to me it's expanding my knowledge and the world of bonsai. I have always been interested in promoting the use of our native plant species which are rather under represented in American bonsai and decided to focus on Elms thinking it would be a finite thing that could be discussed rather quickly. However, as always, I end up making things complicated by asking myself too many questions. So, instead of just talking about using our native species, I thought I'd mix things up a little and talk about the world of Elms and how they infiltrated the American Bonsai hobby the way they did and why. As we will find out, this will encompass the subjects of the Distribution of Elms world wide, American horticulture, the effects of plant disease, its movement through the world and the business of Bonsai. To get this going, lets' first talk about the distribution of elms around the world.

Surprisingly to me because I never thought about it much, Elms are found world wide but are, by whatever reason of nature, limited to the Northern hemisphere of our planet. There are around 25 species of Elm limited to a narrow band around the earth bound to the north by Southern Russia and Mongolia and to the South in the higher elevations of Kashmir. Virtually no Elms are found naturally in the Southern hemisphere. Members of the Ulmaceae family, the Elms are related to Zelkova also a member of the same plant family. Elms in general are very tolerant of a variety of environmental conditions, from dry rocky locations to the wet almost swampy locations of alluvial bottom lands. Only the European Elm (Ulmus glabra) has exacting requirements in that it must be given good drainage for it to prosper.

The species range from large broad spreading trees like americana and parvifolia reaching 80 feet or more to smaller species such as thomasii and villosa only reaching 23-30 feet. All of the elm species have good branching structure and strong root systems, so desired for bonsai. They are all very tolerant of significant pruning of both branches and roots, making them one of the easier plants to collect from their native environment and survive. In common to most elms however, they are subject to a number of diseases and are a favorite of a plethora of insects as a food source. It was the advent of Dutch elm disease around the world that had such a significant impact on the horticultural world, the distribution of foreign species and, ultimately, an impact on the world bonsai community.

Prior to the industrial revolution of the 1830's, horticulture was pretty much a local industry throughout the world with the exception a group of European botanist who traveled the world collecting plant specimens for scientific reasons, but more importantly for purposes of commerce. American horticulture and landscape was in its early infancy and, for the most part, was accomplished through the use of native plant material. The exception to this are the large grand gardens of the wealthy who spent much time and money replicating the great gardens of Europe through the importation of foreign plants, but by and large was very limited in scope. One of the most frequently sited trees in early American art and literature was the American elm (Ulmus americana). We often find it in late 19th and early 20th century prints depicted as the grand street trees of the burgeoning cities throughout the Midwest and eastern United States. The Cedar or water elm was also frequently used as an Americana street tree in its native habitat of Texas, Arkansas, and northern Louisiana. As the American population began to migrate west, they took with them some of the plants with them, and as such the American elm was found from coast to coast. It's funny, people are like squirrels and, wherever they go, they plant what is familiar to them. As the industrial revolution got underway in earnest in the 1850's with the advent of greater transportation flexibility, horticulture in America became an industry. Plants moved from area to area, nurseries started to grow and sell a larger and larger variety of plant material, often imported from foreign sources, to the public. Along with that, however, came the movement of diseases and pests around the world. In 1910 in Holland, the first outbreak of Dutch elm disease was discovered and spread through much of Europe. The impact on the Elms was relatively minor because the potency of the disease was not as significant as what was to come. The disease (spread by the Elm beetle) was spread to the continental United States in a shipment of lumber from Holland to a furniture factory in Ohio in 1928. In the 1940's the disease mutated, but this generation of the disease was much more aggressive and spread though out the world like wild fire. The disease was devastating to the Elms of both Europe and the Americas from which they have fully not recovered to this day.

As a side note, the Dutch elm disease is initially spread by the Elm bark beetle. Once the microfungus is in the tree, it can be spread from tree to tree by contact of the root systems. Often an infected tree will die and new sprouts will come up, but they will usually die within 5 years or so.

The devastation caused by the Dutch Elm disease caused much to change in the US nursery industry. As a result, the industry looked for a replacement tree and through the efforts of the US Department of Agriculture. In 1914, USDA plant explorer Frank N. Meyer sent seeds back from China of Ulmus parviflora for study. Seedlings contributed to the prairie state forestry project in 1935-1942 made their way into the American nursery and landscape industry as a resistant Elm species to the disease. From that initial introduction, Ulmus parvifolia was widely planted in the 1950's and 60's in the United States as an elm replacement as well as tolerance of many climates. Even today one will usually only find Ulmus Parviflora in retail garden centers, in lieu of other American species. In Europe small communities of the native elm survived and have remain healthy even to this day. The European horticultural community began a hybridization program of native species with other species known to have some resistance to the disease and continues to this day.

Now you're asking yourself, what does this have to do with bonsai? Well, there is a relationship in the plant material used for bonsai. In Europe and Asia the native elms are used in bonsai quite often even to this day, even though the Asian U. parvifolia is used as well. In Europe, you see fine examples of U. Minor, U. laevis and U. procera. In Asia, U. parvifolia is the predominate tree used for bonsai in that it is native there and has been used for generations. In the United States, the vast majority of bonsai elm are U. parvifolia because of their introduction into the nursery and landscape industries in the 1950's as a replacement for the native trees. It makes sense that this would be the case in that American bonsai was pretty much started on the West coast by the Niessi Japanese (Second generation American born Japanese around the 1930's) who dominated the nursery and landscape maintenance business on the West coast at that time. The Bonsai art form was initially introduced into the United States by their parents or grand parents who immigrated to the US between1890 and 19ll ( Issei Japanese) who were familiar with U. parvifolia as a bonsai subject in their native Japan.

We've talked quite a bit about the history of elms in bonsai and why some are more prevalent in our hobby than others, but, in the end, one can count on one hand the number of elms that have broad usage. By far U. parvifolia and its cultivars account for 90 percent of the bonsai. As we discussed earlier, all of the elm species have the right characteristics for use in bonsai and should be used far more than they are. Of the American species, all of them, with the exception of U. crassifolia, are native to our area and our attention to them should be far greater then it is. U. alata (winged elm) is an excellent candidate, even though it is a little more difficult to wire because of the wings, but guy wiring is an acceptable method for the simpler wiring. One of the best candidates U. rubra (Slippery or Red elm) is one of the best elms of our area that has many outstanding features. For one, it is now understood to be the only American elm that is resistant to the Dutch elm disease, can be easily wired, significantly trimmed, and collected without difficulty in the early spring.

There is a whole world of Elms that can be used for bonsai, if only they were more readily available. I, for one, would love to try U. castaneifolia for its Chestnut like leaf pattern and U. villosa for its Cherry-like bark. As always, some of the best things are found in your own back yard, so get out there and check things out.