Proceedings Library

I wonder how many of us who met 20 years ago in Cleveland had any idea that the Plant Propagators' Society would reach — in this short time — the stature and the size that it now has.

I know that I speak for all of us who were at that first meeting when I say that this is indeed a most splendid day — a day to remember — for we see here, in this assembled company, the living and working essence of the Society's philosophy. Twenty years ago it was but a dim outline of the clear and simple pattern by which we all now work together.

Certainly our Society is much larger than we then thought possible or even desirable, and I think it says a great deal for both the philosophy itself and the officers of the Society through these formative years, that the inevitable increase in size has in no way diminished or diluted the individual and collective will to maintain our

Apart from the nationally-owned Forestry Commission which operates several large nurseries mainly oriented toward seed production and the privately-owned forestry nurseries similarly organised, production by seed in most English nurseries has not reached an advanced stage of development or sophistication.

It is difficult to be certain of the reasons for this situation but some contributory factors can be isolated. In broad terms the monetary value of items raised from seed is not so high as clonal forms or rare species produced by vegetative propagation. This has an influence on the owner or management who perhaps erroneously imagines that the higher priced items are the most profitable. Most of the nurseries in England are small in physical size and turnover and also they are heavily biased towards the retail trade. This type of business has few resources for large scale seed production in terms of finance or land. The main requirements are for clonal forms to satisfy the

For some time — perhaps a few decades — arborists have projected that virtually all trees used in landscape plantings would be of selected clones. This, of course, would necessitate asexual propagation, usually by budding or grafting. Such propagation requires seedling understocks, except in those rare instances in which the clone is grown on its own

During this time the propagator used lath or brush structures to protect his seeds from the direct sun and rain. Later he used frames that he filled with manure for heat and covered with glass sash or boards for protection from the elements. Prior to World War II the glass house came into great use for seed propagation and is still used as the primary seed propagating structure. The seeding techniques used in benches or beds prior to World War II has been eliminated by the ease with which flats and pots can be sterilized and moved through the nursery.

Today the germinating

There is much botanical and horticultural diversity within Magnolia virginiana L., the sweetbay magnolia. First, botanically, there is the typical variety, M. v. var. virginiana, which is the one most frequently cultivated in America. Its natural range is along the Atlantic Coastal Plain,

More importantly, however, plant propagators work in the presence of the great mysteries of biology because certain aspects of plant propagation involve some of the most mysterious and remarkable phenomena in the whole world of biology. Of these we know very little. I am not referring to the processes of budding and grafting, because when you take a piece of a plant and apply it to another plant it is essentially tissue culture, except that instead of hiring a technician to make up the nutrient medium you hire a stock plant to do it for you. On the other hand, seed germination is an extraordinarily complex and beguiling phenomenon. Some seeds need only water and they germinate, but some seeds, as you know, go through a period of dormancy which is a term behind which we hide our almost

Prevention of wilting. This would be my choice as the most important factor. To prevent wilting of leafy cuttings, turgor within the cutting, once it has been taken, should be maintained. Suggestions have been made to take cuttings early in the morning when they are normally the most turgid and transpiration has had little effect. Collect cuttings in containers of moisture-preserving material, such as burlap-lined baskets or plastic sheets; moisten them as soon

Form of tree. Considerable attention is given to the form of tree grown. Low working, leading to scion rooting, has resulted in loss of rootstock control; now

Deciduous species. Grafting of deciduous species is most commonly done in late winter or spring using scion wood from shoots that grew the previous season. One-year wood is preferable in most cases, but two or three-year-old wood can be used. For example, two-year wood is acceptable or even preferred for figs (Ficus) and olives (Olea), and Leiss (18) reported that with Fagus sylvatica two and three-year-old wood gave best results.

The usual recommendation is to select wood from moderately vigorous shoots, and to use the lower

A review of the Proceedings of the Society supplies a wealth of material dealing with all aspects of graftage dating back to the first published papers in 1952. I read with much interest these papers by Hoogendoorn (2), McGill(16), Burton (1) and Mattoon (15) and was amazed to find that environmental control in grafting presented the same problems then as face us

It is now becoming known amongst nurserymen that 100% takes with hardwoods is a reasonable expectation with a much wider range of subjects than hitherto thought possible provided that material of high rooting capacity is used. Provided also that due consideration is given to season of taking, hormone treatment and to the

An organization known as the National Association of Propagating Nurserymen was formed in 1919 and survived until 1931, when, due to internal problems and the severe economic conditions of that period, it foundered. In 1926 the first of six annual reports was published. At the 1958 meeting of the Plant Propagators' Society, Roy M. Nordine made an appeal for a set

Nurserymen come in all shapes, sizes and kinds. In this complex industry there is the back-yard gardener turned nurseryman, the second or third generation nurseryman, the business entrepreneur engaged in the profession as he might be in any business, and all combinations of these. This industry has many trade organizations at national and state levels. At the national level there are the American Association of Nurserymen, the Mail Order Association, the Plant Patent Owners and perhaps others. At the state level are many state associations.

But there is one organization that is unique, our International Plant Propagators' Society. It is unique in that it is truly an international organization. But more importantly it is unique because the membership is composed almost entirely of

People have been bringing plants from one part of the world to another since the earliest days of civilization. The earliest recorded expedition specifically planned for plant hunting took place in 1495 BC before the establishment of Athens or Rome. Queen Hatshepsut of Egypt sent five ships to the Land of Punt (Somalia) to obtain living specimens of the tree which produces frankincense. Thirty-one living trees were brought back and established in the garden of the Temple of Amon at Thebes

Sailors, soldiers, traders, and later missionaries and government officials often brought or sent home

As plantsmen, propagators and nurserymen, I feel that we have a special obligation to evaluate the "growing" as well as the "aesthetic" aspects of these new plants. As a practicing nurseryman, I consider the basic concerns are: 1) that the plant is capable of

The purpose of this paper is to review three selected research areas of ornamental plant breeding which are

Variation in Japanese Dogwood (Cornus kousa) seedlings. Cornus kousa, the Japanese dogwood, provides a striking example of the variation that can arise when plants are raised from seeds. An amateur horticulturist in the Boston area started a number of C. kousa plants from seeds in 1957. About 80 of these were lined out in a field where they have grown to flowering size. This year one inflorescence was collected from each of 24 trees and these were assembled and photographed. No two were alike. Some had good ornamental characteristics while others were obviously inferior.

Both Cornus kousa and C. florida have small globose clusters of insignificant flowers which are

Each year in spring it produces a mass of small whitish blossoms which are followed in autumn by an exceptionally heavy crop of small bright red fruits which hold their color and remain on the tree into winter. While fruits of some crabapples become soft and ready to be eaten by birds by mid-September and on through autumn, others go into winter in a firm condition and are not suitable for birds until they have been modified by freezing. Malus ‘Donald Wyman’ is in the latter category and this trait is an outstanding feature.

During the cold winter months when snow covers the ground and there is a dearth of food for birds,

Temperature extremes        -41° F to +111° F
Frost-free period                125 days average
Precipitation                       21 inches average
                                                    (15 as rain and 55 as snow)
Soil                                    highly calcareous with a
                                                high salt content
pH                                     6.1 to 7.9 in the A horizon;
                                                higher in the lower soil levels

Research in ornamentals at this institution consists of breeding and evaluating hardy ornamentals, as well as propagational and taxonomic research. The Arboretum contains over 1800 species and cultivars of trees and shrubs representing 120 genera.

¹Rosa ‘Cuthbert Grant’ was introduced in 1967 by H. H. Marshall of the Brandon Research Station. It is a repeat bloomer with brilliant dark red, fully double flowers. The plant is a complex hybrid of the

This organization, first known as the National Association of Propagating Nurserymen, was formed in 1919 and survived until 1931, when, due to internal problems and the severe economic depression of that period, it foundered. The group met in conjunction with the annual convention of the American Association of Nurserymen and hence moved about the country to different major cities each year. Meetings consisted of one night sessions which were supposed to convene at 8 o'clock but rarely did.

One of the first requisites is that you must stay awake; that is you must be attentive and, of course, your physical presence is necessary. Not only is the presence of your body needed but also your mind in a clear, open manner. A wealth of information is given out but then what are we to do about it, how do we digest it, how do we take it home and put it to profitable use?

I think one of the most important things to be considered is how we identify ourselves. You may describe yourself as the manager of a nursery, a hard-driving Simon Legree with a good educational background in horticulture, with a complete staff, a fair amount of facilities, and a liberal boss who gives you some latitude in how you run the operation. What is the company philosophy? How does it fit with your identification of this company? You

What is the relationship of plant propagation and ecology? In a very limited sense this has already been considered in the session dealing with environmental factors. Yet, in the broad sense of the term, ecology goes much beyond this Every time a new plant is propagated from seed, cutting, or graft the propagator has participated in the modification of the environment, even though the effect of a single plant maybe small. If we consider man and his immediate landscaped environment it is interesting to note the many ways in which

Just one

A while ago I was listening to one of those morning talks, "Farming Today", and a large-scale rose grower was saying that today they try to eliminate every hand operation, and they are succeeding. Herbicides have replaced the hoe, machines plant, cut over and lift, and pallets convey the material into and through the sheds and storage. Wrapping, labeling and packing is done by machine and the final distribution is palletized in collaboration with forwarding agents. Orders are sorted, advices and invoices

Everyone who either grows plants or offers them for sale has to report to the Government Plant Protection Service for inspection; thus there are a great number of nurseries registered, though most of them are, more strictly, garden centres. This also includes some who just produce a few perennials, roses, evergreens, etc. in their garden as a part-time occupation I should say that 120 nurseries covers 95% of the total plant production. The plant inspectors are rather strict in their judgment of the general health condition of the plants and are especially checking for virus; thus "outsiders" who do not care about quality etc. soon learn

Preparing scion material. We first planted a stock plant on an east wall, with some protection from the north side. When this plant had established itself after the first year, we waited for young growth to commence, which normally is about late April or the beginning of May; when growth has reached about 18 — 30 inches (45 — 80 cm) and just before the main terminal bud ceases to grow, we cut back to about half its length. If this is not done, it will go on to produce excellent flowering wood for the next season; by cutting back we encourage more young growth to come from the remainder of the stem which will produce the right size and type of material for which we are looking, i e. about 5 — 8 mm in thickness and with no "flowering wood" which normally will not produce a plant after grafting.

Stocks. Stock required for clematis grafting is Clematis vitalba — commonly known as old man's beard or travellers' joy

Despite the difficulties involved, the root cutting method is by far the best way to increase certain plants which do not easily grow from stem cuttings. The Californian poppy, Romneya hybrida, is very readily increased by root cuttings. At Woodbridge, we find this operation is best done in late December or early January.

Stock plants are grown in large pots and planted in our display borders where the flowers are very useful during the summer

Effect of time of insertion on rooting and development. Twenty cuttings of each of 20 cultivars were inserted at fortnightly intervals from the beginning of February to the end of March, 1969. The percentage rooted was generally higher from the earlier

I have had experience in the propagation of this tree over a period of about

A most important discovery by research workers was the role played by hormones in controlling various responses in plants, including root initiation in cuttings, leading to the manufacture and use of synthetic auxins which have become an essential and singularly effective tool in the nursery

There is evidence, however, that auxins are not necessarily used in the most effective way by propagators, underlining the need for applied research of the type done at the East Malling Research Station by N. Nahlawi, whose paper entitled, "The effect of dipping depth and duration of auxin treatment on the rooting of cuttings", won the 1970 Graduate Student Award of the Society

All plantsmen know that plants need water for growth. Water is essential for plants as the major constituent of physiologically active tissues. It is a reagent in photosynthesis and in hydrolytic processes as well as a solvent in which salts, sugars, and other solutes move from cell to cell. Water is also essential for maintenance of plant turgidity.

If we ask what the plant does with all the water it extracts from the soil we can only conclude that it allows most of it to evaporate from the shoots and uses only very small amounts in growth. It has been estimated, for example, that plants may use from 250 to 1,000 pounds of water to produce one pound of dry matter in growth of roots, stems, leaves, and reproductive tissues. Yet we know that if a plant cannot get water from the soil its growth is adversely affected and it may be killed. It should be obvious, therefore, that plants are extremely inefficient in their use of water and this is a matter of concern to all of us.

The

Comparatively few forest trees are raised vegetatively but poplars and willows are grown in the open nursery from hardwood cuttings and several horticultural cultivars, including Leyland cypress and selected clones of elm, are produced under mist indoors. The methods of propagating these are discussed and brief reference is made to recent research on the subject.

Mr. Dufresne, who is a refrigeration expert from Denmark, will be giving a separate paper on technical questions on jacket cooled stores, and I am sure he will answer any questions that members put to him. The first question to which we wanted an answer was, "How long could stock be stored and still remain viable?" For our trial we used 2-year seedlings Picea abies (P. excelsa); these were tied in bundles, bare-root, and put horizontally in slotted crates. Seedlings were put in the store in

Before the jacket cooling system was developed, some very primitive experiments were made in storing plants in normal direct-cooled cold stores, but to avoid drying up the plants it was necessary to pack the plants into airtight bags or boxes because of the very low humidity and the air circulation in these stores. The demand today is storing lifted (and well-ripened) plants from autumn until the normal (or extended) time of next year's planting or lining out with complete preservation of growing abilities without the necessity of wrapping up the plants.

A suitable low temperature (0° C or 32° F) is required to keep the plants dormant

Camellia sinensis × assamica vars. differ in all tea producing countries of the world, each of which has developed techniques which are influenced by local conditions which may not occur elsewhere. Individual concerns within these countries have further developed their nursery techniques to suit their particular requirements. The following is a brief outline of one such method which was developed from the general recommendations of the Tea Research Institute of East Africa

Nursery beds. These consist of 150 gauge polythene sleeves, stapled or spot sealed at the base and perforated in the lower half to assist drainage, stacked upright in beds of 2 to 4000, 10 cm lay-flat tubing being used for plants required for new extensions and 15 cm lay-flat tubing for the larger plants needed for infilling vacancies in mature fields. Sleeve length is 25 cm in the former case and 30 cm in the latter. Over each bed a tent or hoop shaped framework is

Layering This system of propagation is a particularly useful method of propagating small numbers of plants but it is extensive in its use of land and stock material. The parent plants should be planted in well-prepared land at a spacing of at least 2 m square, and allowed one year to establish. The stock is then cut down to a low crown or stool so that in the following year vigorous, strong growing shoots are produced; these will, depending on the species in question, be about 1 m in length. This sort of material has a number of advantages in that the crown of the plant is low, the shoots are flexible and the shoots have a high capacity to root. Simple layering is carried out in spring just prior to bud break; the only important

The emphasis of this paper is on the production of plants under aseptic conditions. As the principles of in vitro culture have been revieved by Murashige (7) in an earlier volume of the IPPS Proceedings and as technological aspects have recently been discussed by Marston (4, 5), this introduction merely serves as a reminder of some of the more important points.

Propagation in flasks or test-tubes entails the growing of a small portion of a plant, the explant, on or in an artificial nutrient medium, generally composed of mineral salts, vitamins, growth substances and sugars which have been dissolved in distilled water. Unless, however, precautions are taken to ensure that everything is sterilised, bacteria and fungi flourish and multiply so fast under these conditions that they swamp and kill the explants. To avoid this, glass containers, with the appropriate volume of medium measured into them, are sterilized in an autoclave or, on a small scale, in a pressure cooker and

It is worth noting at this stage the reasons for erecting this type of house in the nursery. We were faced with a shortage of covered space for growing nursery stock. To this end a cheap form of cover was needed that could be constructed with nursery labour. It had also to be of a semi-permanent nature so that if plans changed it could be moved to another site. Bearing these items in mind it was decided to try the type of house already mentioned.

At the time of erection of the houses, little work had been done with nursery stock grown in this type of house. The basic cultural techniques had to be

The first time I encountered the "overwintering problem" was in 1962, and we hoped to overcome it by avoiding any unnecessary root disturbance. This method entailed taking cuttings in July, using fairly firm material and inserting them in a rooting medium in a deep wooden tray. The trays of cuttings were then placed on the mist bench. Rooting took place slowly by present day standards and eventually the trays were transferred from the mist bench to a cold frame for the winter. A few survived to grow the following spring but by no means enough to make it a worthwhile proposition.

The next attempt took place in 1966

1. Control of Red Bud Borer
                (Thomasiniana oculiperda, Rubs.)
2. Propagation of Leyland cypress
                (×Cupressocyparis leylandii)
3. Excessive callus formation in Leyland cypress
4. Hormone application to cuttings
5. Effect of loss of light in cold storage of conifers
6. Possibility of rooting rhododendrons by in vitro culture
7. Timing of soft wood lilac cuttings.

Ornamental trees are an important crop within the nursery industry and budded trees of the more popular and valued cultivars are recognized as a speciality of the Coles nursery. Nursery Manager, Steve Haines, explained that the budding season for trees normally extends from late May until mid-August. Acer platanoides

Temperature control is achieved by propagators in many ways, utilizing either the natural environment, artificial environments, or both. We can achieve control by locating our operations where the natural temperature regime is favorable and grow plants adapted to that location. We time our operations during the year when proper temperatures are available. We use many artificial methods to control temperature for both heating and cooling: greenhouses,

The nutrition of the stock plant prior to taking the cuttings is obviously a factor, but not much conclusive evidence is in the literature — granted that I may have missed some research reports. It appears that nutrient levels which produce reasonably vigorous growth of the stock plants, without signs of nutrient excesses or deficiencies, result in cuttings giving the best rooting responses. Either excesses or deficiencies of any element are apt to reduce rooting of the cuttings taken from stock plants grown under these conditions. O. A Matkin of the Soil and Plant Laboratory, Orange, California, told me recently that in respect to feeding stock plants, cuttings taken from

The related problem of deciding which of alternative seed sources to use is more complicated and less fully understood. It is sometimes thought that any plant or seed is equivalent to any other of the same name. Experienced plantsmen know that this is seldom true — in fact, have known for many years that selection of proper genetic material can be essential to success in plant cultivation.

What is a plant species? A plant species usually is a collection of individuals grouped together for purposes of classification because they have certain morphological features in common. This in no way implies that they are identical

Therefore, instead of repeating old ideas which we all know are useful, I would like to speculate on newer ideas which I think might be important. Perhaps, at the close of the talk, some of you, from your intimate practical knowledge of seed germination, may be able to prove or disprove my