Volume 20

Please click on an abstract of your choice to access the relevant downloadable papers. Please note, you will need to be logged in as member in order to access the proceeding abstracts.


Author: James Wells

PP: 94

On November 8, 1951, as a result of the initiative of Edward H. Scanlon, the first organizational meeting of our Society was convened.

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


Author: B.E. Humphrey

PP: 188


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


Author: Hugh Steavenson

PP: 192

Some of our Western Region friends may wonder about the purpose of field-grown seedlings. I have visited many west coast nurseries, particularly in California, where trees and shrubs grown from seed never hit the "ground" until finally installed in their ultimate landscape location There is obvious merit in container production and even some field production in starting seedlings in flats in the greenhouse, pricking off into pots and shifting to larger containers or field rows as growth advances; but there are also some limitations and some disadvantages to this procedure as against bare-root production of seedling liners in the field.

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


Author: Bruce Usrey

PP: 195

The seed propagator prior to 1945 believed that the only things that affected seed germination were viability, water, free oxygen, heat, age and maturity of seed, and it was with these things the seed propagator worked with to improve his stand. Once the seeds had been received, treated and sown, the propagator had only heat, and water to work with, as the free oxygen was determined by his media and watering practices.

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


Author: Joseph C. McDaniel

PP: 199

This paper concerns a magnolia species for which seedage methods are well established and in which the past American nursery production has been mostly by seedage or collected seedlings. Named clones now are becoming available, most of them adaptable to cutting propagation. Two of the new cultivars at least, and probably others still to be tested, offer seed sources with which seedling growers can upgrade their production in this species — for uniformity, for wide general adaptability, and for landscape quality — above the average obtainable from unselected seedlings. In this respect they parallel the superior seed sources which are being discovered in many other genera of ornamental trees and shrubs.

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,


Author: Kenneth V. Thimann

PP: 211

I think plant propagators are among the most fortunate of men. In the first place, the work that they do doesn't add to the world's burden of pollution and misery; it works in the opposite direction.

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


Author: Joerg Leiss

PP: 218

As nearly everyone is concerned with the pollution of our environment by humans, it should come as no surprise that, as plant propagators, we have been at work for a long time to control, to a limited degree, the environmental conditions required for rapid rooting of leafy cuttings. I will not try to go back in history to find out when and by whom such controls were first used. However, let us find out a little about the conditions most conducive to rapid rooting of leafy or any other cuttings, and how we control these conditions.

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


Author: Robert J. Garner

PP: 222

Vegetative progagation only. Fruit trees and rootstocks in England are propagated entirely vegetatively. Seedling rootstocks faded away with Hatton's (1) publication of his classical trials in the twenties. Today the fruit tree raisers and growers are eager to exploit the latest findings of rootstock research just as they did the scion variety, but with more certain assurance. Today our growers demand trees on dwarfing rootstocks and at this moment there is a lively interest in the most dwarfing, in our country where winter killing frosts are no hazard. For apples, East Malling is now releasing the very dwarfing ‘3431’, as ‘M.27’, which is considerably more dwarfing than ‘M.IX’, virus-free ‘Quince C’ for pears, selected St. Julien for plums and peaches, and growers are knocking on the door for our dwarfing rootstocks for sweet cherries.

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


Author: G.F. Ryan

PP: 225

The selection of stock and scion material varies with plant species or cultivar. For convenience in the discussion that follows, plants will be grouped under three headings: deciduous species, coniferous evergreens and broadleaf evergreens. There are some similarities in grafting procedures within these groups, but differences will also be noted. Plants of a wide climatic range, from temperate to tropical areas, will be considered under broadleaf evergreens.

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


Author: Lawrence L. Carville

PP: 232

Webster's dictionary defines environment as "that which environs; the surrounding conditions, influences or forces which influence or modify." The plant propagator defines environment as the conditions sustaining or contributing to the life or development of plant tissues. In our present age, it is fashionable to be concerned with our environment and much is being said pertinent to the national environment. As propagators, we are vitally concerned with this subject matter since proper management of the environment within our business establishment is a matter of necessity if we are to be successful in our profession.

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


Author: R.F. Martyr

PP: 238

The term "hardwood cutting" in Britain is almost exclusively limited to denote the ripened wood of deciduous species and would not ordinarily include, for example, the autumn cuttings of narrow-leaved evergreen species — though technically this might be "ripened wood". Within this definition it is true to say that there is a much decreased (and probably still decreasing) use of hardwood propagation techniques in the production of ornamentals. In some nurseries it is a technique that has been dropped altogether and in most others it is restricted to the simplest and most straightforward subjects such as Salix, Populus, Ribes, Spiraea where 100% take can be reasonably achieved.

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


Author: William E. Snyder

PP: 98

At the invitation of Edward H. Scanlon, 68 persons interested in plant propagation met at the Statler Hotel, Cleveland, Ohio, on November 8–9, 1951. The purpose of this meeting was two-fold: first, to hear talks by six well-known plant propagators and second, to consider whether or not an organization of plant propagators should be formed. The result: 20 years later these six speakers at the First Annual Meeting have been followed by more than 450 persons who have presented talks on plant propagation and related subjects and the membership has increased from 68 to 886 persons affiliated with the three regional organizations.

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


Author: C.J. Alley

PP: 244

By grafting, for this report, I will refer to benchgrafting rather than field grafting Propagators that produce plants vegetatively by small cuttings are indeed fortunate. This is completely different from what the nurseryman who grows grapevines has to do. Many parts of California have no nematode or phylloxera problems so it is possible to grow grapevines on their own roots. However, the nurseryman must resort to rooting a cutting that is at least 16 to 18 inches long. In the Coachella Valley of California, where the early maturing table varieties are planted and where the soil is very sandy, growers are not satisfied with cuttings only 18 inches long. A few prefer to have them 3 feet long. This is because they dig a hole 2 feet deep and then bury the cutting so that only the top bud remains above the soil. The lower 1 foot of the cutting is bent over at a right angle at the bottom of the hole to provide a greater surface for root development. However, in many parts of California

Author: Andrew T. Leiser

PP: 249

As moderator, it is my job to set the stage for the speakers who will follow. Therefore, I will not be talking about plants for the future but will briefly review the sources of our present plant palette.

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


Author: David B. Paterson

PP: 251

If anyone had doubts as to the importance of the plant explorer to ornamental horticulture, a careful reading of the catalogs of nurseries, seed houses, and house plant growers would quickly dispel them. It is obvious that without their valuable work in introducing trees, shrubs, and flowering and foliage plants from all over the world, there would be no ornamental horticulture as we know it.

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


Author: Bruce A. Briggs

PP: 258

In man's continuing search for new plants, there is an increasing need for more selective evaluation. There is no special merit in "newness" alone. Sometimes, we rather need a "new" look and evaluation of an "old" plant Our greater mobility today now allows us to evaluate first hand the plant materials of other areas, to bring some back to adapt from other climates, and sometimes to discover improved variations within the species and new cultivars. Improved cultural practices and laboratory facilities give us greater controls over our immediate environment, so that new plant introductions can now take a course and a direction. We can work more directly toward selecting, shaping and breeding the plants required to fill the predicted needs.

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


Author: Kenneth C. Sink, Glen P. Lumis

PP: 264

The breeding of new ornamental plants is beginning to gain momentum in the United States and overseas. This includes efforts on annuals, perennials, woody shrubs and shade trees. A growing number of horticulturists and foresters at academic institutions, the U.S Department of Agriculture, and commercial companies have a primary concern in ornamental plant breeding. Recently, Egolf (1) and Goldsmith (2) reviewed the present status of breeding efforts on woody ornamentals and hybrid annual flowers, respectively. The former report relates the plant species, including Camellia, Chaenomeles, Hibiscus, Ilex, Lagerstroemia, Magnolia, Malus, Pyracantha, Rhododendron, Rosa, Syringa and Viburnum, being studied by some 41 researchers. The latter report presents the current picture in F1 hybrid annuals with special reference to petunia, snapdragon, marigold, zinnia, and geranium.

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


Author: Alfred J. Fordham

PP: 270

When raised from seeds, plants sometimes exhibit characteristics which differ greatly from those of other members of the same seedling lot These variations create many new varieties which a more knowledgeable horticultural public has found increasingly interesting in recent years. Some examples of this are given below.1

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


Author: Alfred J. Fordham

PP: 271

Malus ‘Donald Wyman’ came into being as a volunteer seedling in the crabapple collection of the Arnold Arboretum. It was first noticed in the late 1940s. Observational notes on the flowering and fruiting characteristics of M. ‘Donald Wyman’, kept since 1955, indicated that the seedling had attributes — particularly its fruit — which made it worthy of a cultivar name.

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,


Author: William A. Cumming

PP: 272

The Research Station of the Canada Department of Agriculture at Morden, Manitoba, is located 75 miles southwest of Winnipeg and 13 miles north of the 49th parallel. The following chart lists a few statistics on growing conditions:

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


Author: Bruce Briggs, Robert Garner, Charles Hess

PP: 278

CHARLES HESS: Bob Garner, do you want to start the Question Box tonight, handling the question related to grafting?

Author: Nazir Nahlawi

PP: 292

Factors hitherto not taken into account were shown to influence the rooting response of hardwood plum cuttings to treatment with IBA in 50% alcohol. The depth to which cuttings were dipped in the auxin solution and the duration of the dipping treatment were important, while rooting in cuttings dipped to 1 inch was improved by wounding.

Author: Alfred J. Fordham

PP: 116

Much of the great technological advance made in plant propagation during recent years can be credited directly to the organization known as The International Plant Propagators' Society This unique body has successfully brought together those concerned with the scientific investigation of propagation and those involved in the more practical aspects of commercial plant production. Most people, however, are unaware that its origin is traceable to the existence of a previous and somewhat similar group.

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.


Author: George Oki

PP: 301

I would like to take a little different approach to this problem in order to get down to the "brass tacks" of how to get the most out of these Plant Propagators' Society meetings.

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


Author: F.O. Lanphear

PP: 309

The term "ecology" has become a household word with many connotations Ecology in the strict sense is the science that deals with the interrelationships of living organisms and their environment Frequently this is construed to mean how the environment, particularly the polluted environment, affects plants and animals. However, if one considers the strict definition, the effect of the plant and animal on the environment should also be considered.

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


Author: Ralph Shugert

PP: 314

Ladies and Gentlemen and Guests: For the past several days we have been exposed to a multitude of words of wisdom, have enjoyed a delightful tour of the St. Paul area and, in addition, have enjoyed the camaraderie of fellow propagators and dear friends. In 1953 I had the pleasure of attending my first meeting as a guest of Hugh Steavenson. I recall Hugh's explanation of the International Plant Propagators' Society as being an extremely unique organization, wherein exchange of ideas were freely expressed. This general theme and philosophy is still with us today. We heard on the first day of the meeting the expression of the International Plant Propagators' philosophy as expressed by Jim Wells, and I think it goes without saying that all of us in this room have a bit of this inner feeling, if you will, to plant propagation and its role in the nursery community. Without a doubt, the plant propagator today is a man respected and certainly appreciated by his fellow nurserymen.

Just one


Author: Robert J. Garner

PP: 325

It is old-fashioned to speak about knifemanship today because the whole trend is to do away with it, to make it obsolete. And another thing, it is a bold man who will stand up among his fellow propagators and talk about it. So I want to make a few friends, to take you into my confidence and to discuss our problems together. In that way we may each learn something or at least catch a bit of stimulation to encourage some down-to-earth enquiries and vital reassessment of our practices.

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


Author: Anton B. Thomsen

PP: 328

Nursery stock production in Denmark covers a large field which I cannot cover completely in 15 minutes, but I shall try to give a general picture of the Danish nursery industry today. There are 932 nurseries in Denmark, from quite small nurseries covering less than ½ ha, to the largest one which covers approximately 120 ha.

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


Author: Charles E. Salter

PP: 330

We find that the most economical way of propagating this plant is by grafting.

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


Author: F.H. Eley

PP: 332

The root cutting method of propagation is one of the least used methods of vegetative propagation. It is certainly one we hear little about. The primary reason for this may be the inconvenience in obtaining the propagating material. In most cases the stock plants have to be dug up or else the soil round the roots of the plants must be excavated to expose the roots prior to their removal; at best a rather tedious procedure As this has to be done in mid-winter, it is not surprising that propagators find other ways of increasing their stock.

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


Author: J.G.D. Lamb

PP: 334

In recent years the demand in Ireland for trees and shrubs for amenity planting has increased more rapidly than home production, resulting in a sharp rise in imports. With the increasing interest by nurserymen in modern techniques of production we have initiated at Kinsealy a programme of research into plant propagation to encourage our nurserymen to expand their production of subjects well suited to propagation at home. The trials on the vegetative propagation of Chamaecyparis cultivars summarized in this paper are part of this programme of trials and demonstrations. All cuttings were treated with 0.4% proprietary IBA powder after immersion in a solution of Captan before insertion in a mist bench with bottom heat at 21° to 24° C.

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


Author: Brian Halliwell

PP: 338

× Cupressocyparis leylandii, the "Leyland Cypress", is a bigeneric hybrid having as its parents, Chamaecyparis nootkatensis and Cupressus macrocarpa. It was first noticed as seedlings amongst a batch raised from seed taken from C. nootkatensis in 1888 but since that time it has arisen on a number of occasions, sometimes with Cupressus macrocarpa as seed parent. Stock has been maintained by vegetative propagation and today a number of clones exist to which names or numbers have been given. For a long time this tree was considered as little more than a botanical curiosity. Its true worth came to be realized when its fast growth, hardiness and ability to Withstand exposure to wind made it a desirable tree for planting as shelter belts or in windbreaks. This resulted in extensive propagation but in recent years doubt has been thrown on the value of some clones because it is claimed that they are difficult to propagate.

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


Author: B.H. Howard

PP: 340

Experience and skill are prerequisites for successful propagation, but nurserymen are becoming more aware of the opportunity offered by research for improving existing techniques and developing new propagation methods against a background of decreasing availability of skilled labor and increasing production costs.

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


Author: T T Kozlowski

PP: 123


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.



Author: John Jobling

PP: 342


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.


Author: Henry Jackson

PP: 351

The cold stores at Tilhill are of Danish design, that is an indirect cooled house, or jacket cooled. The stores, one of 10,000 cubic feet capacity and one of 22,000 cubic feet, were both constructed by our own labor working to plans sent from Denmark. The advantage in having such facilities, as many members know, is that nursery stock can be stored bare-root for many months, which means that a greater bulk of stock can be stored; also it is much easier to control humidity than in a direct-cooled house.

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


Author: P. Dufresne

PP: 352

In 1956 the first jacket-cooled store room for nursery plants was erected for the nursery exporting company, Danplanex, of Rødekro, Denmark, and today cold storage of nursery plants has become indispensable for the modern European nurseries. During the past years valuable individual experiences have been achieved in cold storage of all nursery plants.

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


Author: L. Bates

PP: 355

Methods of vegetatively propagating tea

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


Author: P.D.A. McMillan Browse

PP: 356

This subject was chosen for a short talk to this meeting because it is an extremely good example of a group of plants which, although fairly easily propagated by traditional means, can nowadays be produced more intensively by sophisticated, modern techniques.

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


Author: Margaret E. Marston

PP: 359


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


Author: Martin J. Hall

PP: 364

The type of house I intend to relate my address to is based on the prototype Film Plastic Tunnel designed by the Lee Valley Experimental Horticultural Station, Hoddesdon, Hertfordshire. The practical aspects are based on my own experiences with five such houses, each measuring 60 feet long by 14 feet wide erected in September, 1969, and used for the production of ericaceous nursery stock.

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


Author: Peter Wells

PP: 366

The advent of the modern aids to propagation, i.e. mist units, bottom heat and rooting hormones made the task of rooting azalea cuttings fairly straightforward, but this was only half the story; the stumbling block to 100 % success was getting the rooted cutting through the winter and into growth the following spring. So often one ended up with a depressing batch of dead twigs.

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


Author: Brian Humphrey

PP: 368

The subjects discussed include, in order, the following:
  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.

Author: D.C. Harris

PP: 373

On both sides of the A47 road, 3 miles west of Leicester, the urban landscape suddenly relaxes into 65 acres of well-cultivated trees, shrubs and roses. This is the nursery of James Coles and Sons, renowned growers of top quality nursery stock and, on this particular afternoon, host to members of the I.P P.S. A smiling William R. Coles with his son Geoffrey invited the visiting party to see as much as possible of the nursery and to ask questions freely during the brief 2-hour tour. With this hospitable welcome in mind, the visitors divided into small groups and, ably guided by members of the nursery staff, embarked on a detailed and rewarding study of the production areas.

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


Author: Sidney Waxman

PP: 139

Before discussing any of the various aspects of light or its influences on plant growth, it must first be understood that there are three basic factors: light intensity, light quality and light duration which all interact with each other. The overall influence on vegetative growth, flowering or some other response is the product of these three factors operating simultaneously There are many other factors that may alter a plant's response to light; the most important one is temperature.

Author: PD.A. McMillan Browse

PP: 378

(Ed note: The ensuing report is the result of a request from the Executive Committee of the G B and I Region, IPPS, to their members for information, particularly from personal experiences, in the technique of propagating viburnums. Ten persons contributed — R D Anderson, G P Chandler, D M Donovan, R J Hares, S J Haines, B R Halliwell, P A Hutchinson, J G D Lamb, P D A McMillan Browse and K Mickelburgh Mr P D A McMillan Browse collated the information into a report, which was circulated to G B and I meetings in September, 1970. The exercise is a continuative one and we should like to have additional relevant information).

Author: Dale E. Kester

PP: 153

The pattern of temperature exposure resulting from radiation from the sun to the earth is perhaps the most significant environmental factor that controls plant growth and development and thereby determines what kinds of plants grow and where they grow (26). Likewise, control of temperature is one of the most important tools of the plant propagator. Or perhaps, we could better say that lack of temperature control can be the major limiting factor for plant propagation and subsequent growth of the plant for whatever use we make of it.

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,


Author: Richard G. Maire

PP: 164

Numerous researchers have been investigating the factors pertaining to nutrition in various aspects of propagation and some specific findings have been reported. However, it appears to me after reviewing the literature that this is a field that still offers considerable challenge to the plant propagator.

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


Author: Harrison L. Flint

PP: 171

The problem of locating sources of seed for propagation of woody plants has not changed basically for many years. Solutions to the problem are gradually becoming easier, however, because of a better-organized commerce in seeds and better communications among plantsmen, largely through the efforts of organizations such as the International Plant Propagators' Society.

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


Author: Bruce M. Pollock

PP: 179

This afternoon, in treating my assigned topic, "Dormancy and pretreatment," I face a difficult task. I am told that I must provide a "take-home" lesson. Unfortunately, most of you know far more about dealing with dormant seeds in practical propagation than I. Even more unfortunately, I have just completed two chapter-writing assignments on seed germination At the conclusion of these assignments, I found myself depressed by the relative lack of scientific progress in the field during the last 30 years. If you review the scientific literature of the 1930's, you will find almost all the ideas we use today. Under these circumstances, I face the problem of providing a "take-home" lesson with some trepidation.

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