Volume 21

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Author: Lloyd E. Joley, Karl W. Opitz

PP: 67


In 1960 the senior author presented a report (8) to the Plant Propagators' Society describing experiences in propagating trees of the genus Pistacia, especially the fall-coloring shade tree Pistacia chinensis Bunge. Since then, there has been an upsurge of interest in California in the propagation, planting and growing of the pistachio nut of commerce, Pistacia vera L. Because of its timeliness, this paper will bring the subject of Pistacia propagation up-to-date.


Author: Betty Ransom Atwater

PP: 104

Our knowledge concerning the nature of the germination process in seeds constantly progresses and we are gradually beginning to understand some of the complex physical and chemical mechanisms which control a seed and determine when germination will occur. The preservation of the species has been assured by the incorporation of various delays in the growth so that all of the seeds will not germinate at once. This unevenness of germination is especially noticeable in perennials and in native and ornamental plants. Most of our common vegetables and flower annuals have been selected over so many years that fast and complete seed germination is normally expected of them.

Before planting, or when a poor stand is realized from a lot of seed, it is possible, in the laboratory, to examine the seed and determine whether it is dead or dormant. Various standard techniques may be used: the excised embryo test; or the seed can be allowed to fully imbibe water, then it can be cut and put into a


Author: Otto Martens

PP: 110

When we think, read or dream of the tropics, nothing comes into mind faster than soft balmy air, blue lagoons with white beaches, palms swaying in the breeze, and glorious sunsets as inviting background for the silhouettes of majestic graceful Cocos nucifera.

The International Airport in Los Angeles has taken advantage of this "tropical" thought association for commercial reasons: The winter traveler from Canada, from the blizzardy plains of the middle west, or the snowbound eastern states, is made to believe that he landed right in the tropics on stepping out of the plane into all the palms that wise and skillful landscape architects placed in and around the air terminal in groups and in groves.

Limitation of palm habitats and uses makes familiarity with this plant group non-existent to some and restricted to those of you from winter-cold and desert-dry areas. So, to understand our topic easier a few remarks on physiology and ecology may be in order. Palms are the plants most valued


Author: Ralph Shugert

PP: 118

One day several weeks ago I had an opportunity to reread the Proceedings of the Seventh Annual Meeting of the National Association of Propagating Nurserymen which was held on June 23, 1926 in the Kentucky Hotel, Louisville, Kentucky. This was the Proceedings of the first meeting, printed and recorded for this astute organization, and showed the interest in plant propagation, as well as the camaraderie of propagators some 45 years ago. There were several items of fascinating interest from this meeting and one that immediately came to mind was the adjournment at 11:00 P.M.! Apparently even in the earlier days, plant propagators just did not give up but carried meetings until the last hour. There was also comment regarding planning being relative to practicability, and a direct quote from Professor A. C. Hottes points out this fact.
      "Asparagus sprengeri, a common florist plant, as all of you
      know, was grown in a few garden conservatories for years
      before anyone thought it might be of

Author: William J. Curtis

PP: 122

MODERATOR CURTIS: Who will be the first one to present an idea or an innovation? Who would like to come forward and present it to this group?

JOLLY BATCHELLER: Bill, I saw something just last week that I think is most interesting. At the California nursery convention in Palm Springs I saw a new type of pot which I think is excellent. I'm not boosting a product but it answers questions that some of us have. Many of us use a "spaghetti" system for watering and there are many different ways to attach the end of the tube to the container. They vary from a little lead weight you drop in—to a spike that you put the tubing over; and these cost money. The tubing itself isn't too expensive but the little plugs are. Someone has come up with a better idea. I think it's real good. They have taken a plastic pot and they have made a bulge on the side of it. My perspective in drawing these is a little bit difficult, but taking a view from the top, here is a normal pot and on the edge


Author: Robert M. Warner

PP: 125

This report will describe a technique which is widely used by nurserymen in flower crops but, as far as I know, is little used for woody plants such as citrus. I refer to the use of photoperiod control which could reduce the time required to bring young trees to marketable size.

Until very recently most citrus varieties in Hawaii were grafted on Rough lemon rootstocks or were "air layered." Only very recently the citranges, Cleopatra mandarin, and sweet oranges have come into use as rootstocks. Trifoliate orange has not been used by nurserymen; it was believed to be too slow in growing, taking 3 or 4 years to reach grafting size. When lined out in the field it made almost no growth from September until the following April or May. The common explanation was that it needed winter chilling. Temperatures near sea level in Hawaii are seldom lower than 65° F. and average in the high 70's which is considered unlikely to be a limiting growth factor for citrus.

We subjected rootstocks to three


Author: Charles E. Hess

PP: 130

Since man recognized the needs and benefits of reproducing plants asexually and, more specifically, propagating them by means of cuttings there have been many significant advances which have made the technique more efficient and have extended the range of plants which may be propagated by cuttings. I would like to review the techniques and advances, pointing out some of the major contributions, showing the blend between art and science, and finally demonstrating that there still remain areas in which answers are still wanting and opportunities for research abound.

Early propagators quickly realized that one of the major problems which must be solved when propagating plants by cuttings is to control water loss. The bell jar provided one solution. It provided a restricted volume of air which could become quickly saturated with moisture, either from evaporation from the media, or from water vapor transpired by the cuttings. When the water vapor in the air surrounding the cuttings


Author: Andrew T. Leiser, Richard W. Harris, P. Lanny Neel, Dwight Long,

PP: 135

Trunk development of young container-grown trees was strongly influenced by pruning and staking practices. Trees were produced which were able to stand without support when planted in the landscape. This was done by eliminating stakes, leaving lateral branches on the trunk and spacing plants so their tops were free to move Even though rigidly-staked trees with their lower limbs removed grew taller, they developed less caliper at the trunk base, much less taper to the trunk and smaller root system. Most of the trees staked during production were not able to stand upright when planted out.

Author: Richard W. Harris, Andrew T. Leiser, P. Lanny Neel, Dwight Long,

PP: 149

The spacing of container-grown Betula verrucosa Ehrh., Eucalyptus sideroxylon A. Cunn., Dodonaea viscosa "Purpurea" Jacq., and Liquidambar styraciflua L was studied at two California locations in 1967 and 1968 As area per plant increased from can-to-can spacing, the plants grew more in trunk caliper and taper, and in weight of roots and branches plus leaves, but less in height and weight of trunk. At the closest spacings, the lower foliage was sparse giving the trees a leggy appearance. Adequate spacing about twice the can-to-can area, the first season gave benefits of increased trunk caliper and fuller foliage with a minimum sacrifice in height growth.

Greenhouse trial with Liquidambar and Zea mays suggest that the greater growth of closely-space plants may largely be due to less movement. Height growth was reduced at least 50% by a daily, 30-econd period of trunk motion


Author: O. A. Matkin

PP: 162

In the last 10 years there really haven't been any new innovations. There has been a great deal of change from systems "by guess" to systems "by design." It was well over a decade ago that a "system" was proposed. The purpose at that time was to remove guesswork, chance, and frequent misfortune from the procedure of growing plants, particularly in containers. Since that time there has been a startling and worldwide change in philosophy and procedure in the preparation and handling of growing media. Although the approach has fostered the use of ingredients which contain no soil, its utilization has led to greater understanding and more intelligent use of "natural" soils.

Reference is made, of course, to the UC System of Producing Healthy Container Grown Plants. It is still available as Manual 23 from Agricultural Publications, University of California, Berkeley, California


The early development of suitable growing media for containers was greatly hampered by man's inability to recognize the


Author: Oliver A. Batcheller

PP: 171

As nearly 20% of the plants commonly used in southern California originated in the Australia-New Zealand area, I felt a study of (a) the nursery industry, (b) the plant materials they use, (c) the institutions training men for the horticultural fields and (d) arboreta, botanic gardens and municipal parks would be of particular interest and value to the Ornamental Horticulture Department and California State Polytechnic College, Pomona, California.

As I think back over the attitudes and philosophy of education as I perceived it in both Australia and in New Zealand, there is a great similarity to that found in Central Europe. It is quite distinct and different from that found in the United States, and one which I feel is better not only for the students but for the country as a whole. In both Australia and New Zealand it is recognized that all students are not college caliber and that all students do not learn either at the same rate or by the same means.

Our visit coincided with the


Author: Robert L. Gonderman

PP: 76

In attempts to root cuttings of difficult-to-root plants, a number of variations of lesser-known methods have been tried. I have had some moderate success in rooting cuttings of pines, oaks, and eucalyptus, and perhaps our methods may enable propagators to produce better landscape plants more easily and cheaply.

Vegetative propagation of desirable clones is becoming more and more practical as we apply our present knowledge to old rooting problems and learn to benefit from past experiences, such as we may learn at this meeting. Our mission-oriented research has permitted a few publications, so some of you already know of some of my work.

We may think of rooting as the result of expression of the interaction of root promoting and inhibiting factors metabolized within the plant itself. Production and concentration of such factors may be investigated by taking cuttings at various growth stages—before, during, or after a flush of growth. With the assistance of my class


Author: Clyde L. Elmore

PP: 184

Management of most undesirable plants in the nursery or landscape is possible with herbicides available today. New chemicals are on the horizon for use in ornamentals which will make this costly job easier and cheaper in the future. With the move toward "low maintenance" and "greenbelting" there will be a greater dependence upon chemicals to manage the environment. To get the most from these chemicals their effectiveness must be maximized, and they must be used safely. However, it should not be assumed that chemicals can solve all plant maintenance problems nor replace proper management.

The herbicides discussed here may not be currently labeled and recommended by the manufacturer, thus they should not be construed as recommendations by the University of California. Presently, there are few herbicides that are labeled for use in ornamental containers so I can only report research findings. In ground covers and plants in the landscape, several herbicides are available and have


Author: Kenneth F. Baker

PP: 191

It is a truism that there are two sources of plant disease organisms — the soil (including organic matter and water) and the host plant. Thus disease control in the nursery comes down to (a) the use of treated or pathogen-free soil, (b) use of pathogen-free propagules or planting stock, and (C) routine sanitation to keep them both clean.

Author: P.A. Thompson

PP: 211


Stocks of seed of horticultural and agricultural crop plants must possess germination characteristics which result in rapid germination of a high proportion of the seed to produce evenly distributed, evenly developed stands of plants. Amongst crop plants particular restrictions in the range of conditions which result in germination may limit the geographical range of the plant or determine particular procedures for its cultivation; for example, high temperature sensitivity of leek seed prevents germination in low latitudes or during the summer in higher ones, and the requirements of celery seed demand greenhouse conditions for successful germination in the spring.

Since it is possible to find dormancy mechanisms still restricting germination in seeds of a crop plant as ancient as the leek it is not surprising that such mechanisms should be present in the seeds of plants taken more recently into cultivation, such as hardy ornamental nursery stock, both shrubby and


Author: P. Dummer

PP: 228

There has over the last few years been a great demand for trees and shrubs in large quantities, and as a result a much larger and improved seed sowing programme has been built up.

Author: A. Turner

PP: 230


Nature has provided many ways by which we can increase stocks of lily bulbs but the rate of increase by bulb division, as in Lilium hansonii, by bulblets below ground, as produced by L. speciosum, by the rhizomatous bulbs of L. pardalinum, or the stoloniferous bulbs of L. superbum, is far too slow for most of us. A few species and hybrids form bulbils in the leaf-axils at flowering time and, while these can be collected in quantity and grown on, the two main methods adopted for the propagation of lilies involve the use of bulb scales or of seed


Scales. That universally useful item—the polythene bag—has made propagation by scales so simple an operation that I need spend very little time in describing our method. We take our scales in late summer or autumn when the lifting and transplanting of lilies is normally taking place. We drop the scales into a polythene bag, shake them up with enough PCNB dust (Quintozene) to give them all a protective coating then add a


Author: Peter A Hutchinson

PP: 233

The following notes have been made with reference to the species listed below:

Acer campestre, A. cappadocicum, A. circinatum, A. crataegifolium, A. davidii, A. forrestii, A. ginnala, A. griseum, A. grosseri, A. grosseri var hersii, A. palmatum, A. palmatum ‘Atropurpureum’ A. pennsylvanicum, A. platanoides, A. pseudoplatanus, A. rufinerve and A. trautvetterii.

Source of seed. Collection of seed from local sources is desirable generally; not only is it possible to collect at the optimum time but the seed can be selected from trees with desirable characteristics.

Seed of a limited range of Acer species can be purchased, usually from foreign sources, but results from these are often variable. This variability can be attributed to the drying out of the seed coat which, in turn, leads to the embryo becoming completely dormant. The drying of the seed does not necessarily mean it will not germinate, but germination tends to be erratic.

Seed collection. Due to variability in the time of


Author: Christoper C. Fairweather

PP: 235

Cuttings of Exbury and Knaphill azaleas are taken during late May and early June. The first cuttings are from container plants grown under glass, followed by soft cuttings from outside plants Cuttings generally are about 3 inches long and, from a long shoot, two cuttings can be made. The apex bud is removed from all cuttings and the leaves reduced to about five.

The cuttings are rooted in old span-frames running north to south. The frames have heating cables with individual thermostats for temperature control. Prior to putting in the cuttings, these frames have a layer of sand over the cable, followed by one foot of leaves for drainage and for preventing the mixture from becoming too compacted and, finally, 6 inches of rooting medium, consisting of 75 % sharp sand and grit and 25 % medium Irish moss peat. The rooting medium is allowed to settle, given a drench of 1 % IBA, diluted to 25 c c per pint of water. One gallon of this mix is watered over about three square yards.



Author: A.I. Campbell

PP: 236

Many nursery catalogues list between 10 and 20 ornamental Malus species, and with the introduction of new cultivars, usually from America or Holland, the popularity of this group of trees seems to be increasing

Few other ornamental shrubs or trees have such valuable attributes and, although ornamental Malus are primarily grown for their spring flowers, many are attractive at other times of the year. Some, for example Malus ×. purpurea ‘Lemoinei’ and M. tschonoskii, have interesting coloured foliage throughout the summer, while others have highly coloured fruit and foliage in the autumn.

The trees are usually sold after 3 or 4 years in the nursery as standards or half-standards. Seedling crab rootstocks are commonly used because propagation difficulties have increased when clonal rootstocks are used. The problems have taken the form of bud failures with some cultivars, while in others the growth rate has been unsatisfactory and dieback has been common.

One of the main factors causing


Author: Tom Allen

PP: 245

Grafting. The Clematis vitalba rootstocks are lifted and laid in thinly in the autumn. Stock plants of the scion varieties should be chosen carefully because only strong healthy plants are suitable. These are potted into 5 in. pots using John Innes 3 compost and set up in a house with temperature of 55° F. at the end of December. By the end of January they will have made about four feet of growth and grafting may commence. Rootstocks should be washed as clean as possible. A single side-graft is used; the length of the scion cut exceeds slightly that of the cut on the rootstocks, as the tongue of scion wood protruding below the tie of fine raffia assists scion rooting.

After grafting, the plants are potted as deeply as possible into 2½ in pots in John Innes seed compost, so that only the leaf and bud is left above the soil. The plants are set into a closed case with a bottom heat of 70–80° F. and watered well. After 2 or 3 weeks callus will form on the top of the stock and the bud


Author: A.R Flint

PP: 246

The main reason for choosing our particular site in the Midlands for growing soft and berried fruits was the soil. It is ideal, in our opinion, for producing a strong fibrous root system which, though important to all plants, is especially so with berried fruits. In texture it is a sandy loam overlying water-bearing gravel and is, therefore, well drained and low in mineral nutrients Regular fertilizer applications and FYM, when available, ensure that the plants remain healthy; a heavy rainstorm can wash a fertilizer application straight through but, on the other hand, during a dry period we find our irrigation system invaluable. The spring of each year seems to bring a regular dry period which can hinder the establishment and growth of plants considerably. Whereas a large number of various kinds of shrubs can be planted fairly late in the year and suffer no ill effects at all, berried fruits to be planted early to get good growth.



Author: Edward F. Frolich

PP: 79

Seedlings of many plants produce pronounced tap roots in their initial stage. This is especially characteristic of materials from arid and semi-arid areas such as the southwest of the United States and parts of Australia, South Africa, and the Mediterranean region. When transplanting from the seed flat to pots, it is necessary with these materials to drastically reduce the size of the root system in order to avoid bending of the roots. This very often results in loss of the seedling.

One way to overcome this problem is by root pruning the seedlings prior to the transplanting operation. In the past this was sometimes done by using a material toxic to roots in the bottom of the flat. Copper was most commonly used, either as a screen laid in the bottom of the flat, or by coating the flat heavily with copper naphthenate. This is effective in killing the growing point of the taproot, but there is a danger of getting an excess of copper into the seedlings, which could lead to various


Author: J.L.W. Deen

PP: 248

In this short review of the use of low polythene tunnels for rooting cuttings it will not be possible to consider all aspects of the technique. The system used at G.C.R.I. will be described and some observations will be made on its use.

The important advantages of low capital cost and labour saving come from the simplicity of the technique and I have tried, therefore, to maintain this simplicity wherever possible.

Tunnel construction. The Tunnel design is basically that widely used in Great Britain for protected strawberry cropping. The wire hoops which support the polythene are bent into the required shape (Fig. 1) on a former from lengths of galvanized wire (8 swg with a tensile strength of 50 ton/in ). The hoops are spaced 30 in. apart along the tunnel (Fig. 1). Polythene sheet 6 feet wide is tied to a stake at the end of the tunnel and stretched over the hoops. It is secured by lacing two lengths of polypropylene bailer twine under alternate loops on either side of the tunnel (Fig. 1


Author: D.M. Donovan

PP: 252

The method about to be described was developed where a few hundred plants could be produced from a few stock plants, and where facilities are limited to cold frame protection, with a slightly heated house to grow on the rooted cuttings. It was inspired by a few unsold and unpruned plants left to overwinter in a cold house. These developed dwarf shoots in March and April, which were removed, rooted and produced excellent plants by autumn.

Propagation and Production. Well grown stock plants are covered by a frame light in March to protect the breaking buds on last year's growth. When several little shoots have two fully expanded leaves, the upper portion of the stem carrying them is removed to force the lower buds to break and be given similar treatment subsequently.

The shoots are pulled off and the remnant of last year's wood trimmed away; then, having dipped them in rooting powder and boxed up for the mist unit, rooting occurs quickly and potting-on may begin in 17 days. Rooting medium may be


Author: J.S. Coles

PP: 254

For many years grape growers have bench grafted their cultivars on American rootstocks resistant to root aphis (Phylloxera). Since this technique is usually carried out indoors during early spring it has been relatively easy to construct machines which facilitate the operation. Simple matching "joints" are made in both rootstock and scion, and grape vines would seem to be easily propagated by using this technique.

Bench grafting of fruit trees has been practiced in this country only to a very limited extent but at Long Ashton interest in mechanizing this technique was aroused when considerable quantities were required for an experimental purpose.

Whilst grafting machines are available in Europe a certain amount of difficulty was encountered in the purchase of a suitable machine, therefore a purpose designed tool was constructed. Various types of "joint" could have been used but from carpentry experience a mortice and tenon is the easiest to manufacture yet probably the most efficient in


Author: Geoff J.E. Yates

PP: 257

While some nurserymen are practicing ways of rooting larger and still larger cuttings to shorten the time between rooting and sale, I have begun to look for ways of propagating ground-cover plants commercially using the least possible plant and container material and, in some cases, to remove the need to stick individual cuttings or to pot or lift from the field. These alternatives are not new, but their use to mass-propagate plant material economically can be pursued with advantage.

Why should it be necessary to consider any new techniques when the majority of ground-cover plants are very easy to propagate and usually make a profit, and when the small numbers now produced are sold at prices as high as those asked for the normal run of flowering shrubs or perennials? In answer, if ground-cover is to be mass-planted as it must be to be successful, the plants offered in Great Britain will have to come down in price to an equivalent level to that of bedding plants and they need to be


Author: Brian H. Howard

PP: 267

Nineteen similar experiments were carried out on 16 nurseries by members of the Society.

Treatments, comparing the effect upon a range of species of making a basal wound, either before or after auxin application, together with non-wounding, gave results of three main types which appeared to be in part related to the kind of auxin preparation used, rather than the species.

  1. Wounding before auxin treatment was beneficial, with the suggestion that this was through improved uptake of IBA applied as a powder formulation.
  2. Wounding before auxin treatment was also detrimental, usually when IBA was applied in a readily absorbed alcoholic solution, suggesting supra-optimal uptake through the wound.
  3. With some subjects wounding was beneficial irrespective of the time of auxin application

The value of a better understanding of these processes is discussed relative to the need for achieving optimal conditions for propagation.


Author: John B. Gaggini

PP: 275


This study was made during my employment in the Ministry of Agriculture, Fisheries and Food when I was employed as a Horticultural Advisor. All the time studies referred to here were made on the nursery of Messrs. John Waterer Sons and Crisp and I would like to thank the management and staff for allowing me to undertake this work and to submit this paper to the I.P.P.S.

The reasons I chose to study bench grafting were that, as an area of work, it seemed to be unduly complex and time consuming in terms of output.

My objectives were to: (1) Eliminate unnecessary work; (2) To simplify the process; (3) To make it a more pleasant job; (4) To speed up work throughout.

The first question to be asked is—what is the end product? In this case, a grafted plant in a closed frame is required and all work must therefore be directed towards reducing the time taken to achieve this end; in so doing, one must eliminate or simplify the job elements. Any alternatives should be judged on


Author: David Clark

PP: 293

DR. B. HOWARD: Has anyone any information—with references if possible—on whether the form the resultant plant is influenced by the position on the stock plant from which the cutting is taken?

J. WELLS: There are a number of simple illustrations of the effect of taking cuttings from different places on the parent plant. Taxus cuspidata comes to mind; if you take a cutting from the side of the plant you get a spreading type plant. If you want an upright form (i.e. to continue the natural habit which is produced from seed) then you must take a terminal cutting. The same thing is true of a number of Piceas, and Picea abies ‘Nidiformis’ is, I believe, produced in that way. This is true of Sequoias also.

D. HARRIS: What has been said of the Japanese yew (Taxus cuspidata) is equally true of the Irish yew (Taxus baccata ‘Fastigiata’).

P. THODAY: It is interesting that all these examples belong to the Coniferae. I think that the effects are rather more subtle in the Angiosperms compared with the


Author: D.A.J. Little

PP: 297

Stocking of the nurseries commenced in January, 1970, and it is hoped that the following notes on our experience to date may be of interest to others starting from scratch under tropical or sub-tropical conditions.

Climate. Lilongwe is situated 14° south of the equator, at an altitude of 3,500 ft. Annual rainfall is about 33 in., almost all of which falls between late November and early April. Mean relative humidity during January–February is approximately 85%, falling steadily during the dry season to 52% in October.

Mean temperature throughout the day rises to 74° F. in November and falls to 59° F. in July. Occasional frosts are experienced during June–August. Mean surface wind speed is approximately 4 mph in January and February, increasing steadily during the dry season to reach over 7 mph in October. Climatic data is shown in Table 1.

Leaf fall of most trees begins in June and much vegetation is defoliated by August. Many shade trees and shelter belts are, therefore, ineffective


Author: Joseph Dallon Jr, Dominic Durkin

PP: 324

Geraniums (Pelargonium hortorum Bailey cv Carefree Deep Salmon) were cultured from seed to maturity using growth retardants, and environmental conditions known to affect flowering in a number of plant species High intensity lights and growth retardant treatments were effective in reducing the time required to flower. Geraniums normally require an average of 100 – 115 days to flower, depending on the variety. A study of shoot tip morphogenesis revealed that flowers are initiated at the seventh week, indicating that the process of flower differentiation and development in geraniums is a relatively slow one.

Author: Rick Henny, Paul E. Read

PP: 331

Cuttings from selected clones of deciduous azaleas, specifically hybrids resulting from reciprocal crosses of Rhododendron × kosterianum2 × R. roseum, which are winter hardy in Minnesota, were successfully rooted with plastic-tent propagation. Rooting under mist was unsuccessful because of hard water and subsequent salt buildup on cuttings. Best rooting occurred in a 1:1 peat-vermiculite or a 1:1 peat-perlite medium, but no single rooting compound gave consistently superior results Succulent cuttings in the elongation stage of growth, having expanding leaves, and cuttings with fully expanded leaves but no terminal bud formation rooted well.

Author: Dieter W. Lodder

PP: 80

Syringa vulgaris ‘Lavender Lady’ is one of the few cultivars of this species which performs reasonably well under Southern California conditions and is, therefore, of economical importance to nurserymen in this area.

Unlike the French lilacs which are budded or grafted, S. vulgaris ‘Lavender Lady’ is normally propagated by softwood cuttings. This plant is not incompatible with the commonly used understocks such as Syringa vulgaris, Ligustrum, or Forsythia, but it is raised from cuttings because its growth is slower than that of these understocks and, if grafted, would result in extremely heavy suckering from the understock.

Success with the rooting of softwood cuttings of S. vulgaris ‘Lavender Lady’ at Armstrong Nurseries was unpredictable. Through experiments, a successful method was found which is described as follows:

Softwood cuttings are taken as soon as new spring growth was available which is in mid-March in Southern California. Nodal cuttings are taken and stuck into flats filled with a


Author: John B. Roller

PP: 340

We became interested in rooting softwood juniper cuttings under mist about two years ago. Our interest was brought about by a new customer wanting a very large quantity of rooted juniper cuttings to be delivered in November and December. We received the order about the middle of June. This presented quite a challenge to produce this large number of plants on such relatively short notice, out of our normal season and not on our production schedule.

We began taking the cuttings the first week in July and finished about the middle of August. We started taking the varieties that, in our experience, rooted more slowly first, and finished with the more easily rooted varieties.

The cuttings were in soft growth, but we cut them back far enough to get into the bark area that had begun to mature enough to change to their naturally brown color of firm wood. Then we made the basal cut and trimmed off the very tender tips, leaving about a 5 or 6 inch cutting. All cuttings were treated with Hormex


Author: Choong IL Lee, H. B. Tukey Jr.

PP: 343

In Euonymus alatus ‘Compactus’ plants grown under intermittent water mist during September, leaf senescence and onset of dormancy were delayed and natural root-inducing substances accumulated in the leaves Consequently, stem cuttings from plants grown under intermittent water mist rooted easily, whereas cuttings from non-misted plants rooted with greater difficulty. When rutin, a substance similar to those which accumulated in misted leaves, was applied with IBA to stem cuttings from non-misted Euonymus, the cuttings rooted as well as cuttings from misted plants. These results provide an additional explanation for the great success of mist propagation techniques, emphasizing that many substances in addition to auxins and rooting cofactors may play a significant role in rooting.

Author: James S. Wells

PP: 351

Your Plant Evaluation Committee met four times and I am glad to say...[continue with rest of text]

Author: Harry W. Hopperton

PP: 360

Our first step in budding Quercus varieties is to line out our 2 year Quercus palustris seedlings in the early spring. This seedling is grown for one year.

Early in the spring of the following year, we go in and cut the seedlings back to ground level. After secondary shoots start to appear and have made a growth of 5 or 6 inches, we take off all shoots except one. In early July or August depending on growing conditions, while the shoots are vigorously growing, we start to bud. The following year when new growth appears, we cut back to the eye and the budded tree takes over. It is extremely important to have good budwood with big eyes. In the spring we severely trim our stock trees from which we cut our buds so that they produce lush, plump buds. I cannot overemphasize the importance of good plump budwood.

Another successful method we use for budding Quercus is to go into a block of young Quercus palustris with a caliper of from 1 to 1½ inches and insert a top bud about 5 to 6 feet


Author: David G. Leach

PP: 362

The breeding of rhododendrons is in many ways akin to H. L. Mencken's description of marriage; "it is", he said, "like reaching into a bag of snakes and hoping to come up with an eel". The breeding of rhododendrons for garden decoration began just 150 years ago when Michael Waterer at the famous Knap Hill Nursery in England crossed the N. C. Catawba Rhododendron with the Rosebay Rhododendron. Some years later there was introduced the scarlet flowered tree, R. arboreum which came from India. It created a sensation when it flowered in England for the first time and a hybridizing explosion began which has never ceased. Before long, the opulent R. griffithianum, another Asian species with 6 inch white flowers arrived on the scene; this too is a tree-like species and is very tender. To produce hybrids which were hardy enough for general cultivation in England the English breeders crossed the tender exotic rhododendrons with the American natives, with R. ponticum, a species from Asia Minor

Author: Richard A. Jaynes

PP: 366

Mountain laurel occurs in many forms and superior selections are available for propagation. Red-budded and white-flowered laurels come true from seed if both the seed and pollen parents are of similar kind. Seed sown in a greenhouse in November will produce plants of sufficient size by the following June to transplant into outdoor beds. Although of limited commercial value, grafting on forced stock in early spring or on unforced stock in June is successful. Clones vary in their ability to root from cuttings and display an increased reluctance to root as the stock becomes older. Cuttings from cuttings or young grafts root more readily than cuttings from the original stock plant. The more "juvenile" the tissue, the more readily it roots. White-flowered and red-budded laurels can be propagated from cuttings by using seedlings of known pedigree as stock plants.

Author: John J. McGuire, Vincent H. Vallone

PP: 374

Cuttings from twelve clones of Ilex, Rhododendron, Sciadopytis, Magnolia and Vitis (woody ornamental plants) were tested for rooting response to combined treatments of benomyl and indolebutyric acid. Response was variable Better rooting was obtained with combined treatments in clones that are normally difficult to root Clones that normally root easily did not show improvement in rooting when benomyl was used with IBA. It is suggested that benomyl may act as a mobilizer in stimulating rooting.

Author: Joe Cesarini

PP: 380

At Johnson Avenue Rare Plants Nursery, I used to propagate cultivars of Carpinus betulus by grafting them, during the winter months, on previous spring-potted understock of Carpinus betulus or Carpinus caroliniana. The grafting was done in the greenhouse at a temperature of 65° F, using the modified veneer system. I was somewhat annoyed by the unpredictable results so I explored a different way of propagation.

Author: E. Stroombeek

PP: 382

This "Propagating Experiences" panel we have embarked on now will likely turn out to be the surprise package of our annual meeting since it is open to so many interpretations.

It took our moderator, Zoph Warner, who was responsible for arranging this discussion, a great deal of persuasion to convince me that I ought to participate on this panel. Not only do I suffer from a liberal amount of stagefright when it comes to giving a talk, but I simply could not get excited about the subject: Propagating Experiences—Old and New.

I could not help but think that here we have a highly successful Plant Propagators' Society, which for the last 20 years has made great strides in promoting and discussing the newest techniques in the field of ornamental horticulture, and here am I trying my darndest just to keep up with them. How in the world can I tell you good people something that's really new in plant propagation?

And as far as old propagating experiences are concerned, here again it is all well


Author: Case Hoogendoorn

PP: 384

As we all know, everyone all these years has used Viburnum lantana as a viburnum understock, either for budding or grafting. However, over 30 years ago we stumbled into using Viburnum dentatum. The reason? We did not have any V. lantana that year, but did have V. dentatum—so we used it hoping for the best. We not only found it satisfactory, but far superior to V. lantana. When we used V. lantana, we were always bothered with black spot, which develops about .mid-August. Naturally, we had heavy leaf drop which weakened the plants. Ever since we have used V. dentatum we have not been bothered with black spot, consequently we have stronger plants and better growth.

Now a word about the V. dentatum seedlings that we use. We always try to get a strong 1-year seedling, grafting size. The reason is that a 1-year seedling does not have as many sucker buds as a 2-year seedling or transplant. Before we start potting these seedlings we trim them and start to eliminate the danger of suckers


Author: Ken Inose

PP: 82

The source from which we get our pumice is on the Eastern slopes of the High Sierras near Bishop, California. It is mined, screened and graded at the mine and delivered to our nursery in bulk. It is not heat treated and is chemically inert with a neutral reaction. The chemical composition of pumice is as follows:

Author: John Ravestein

PP: 386

I was told not to talk too much about the old plant propagating ways. I don't agree with that view; we are all becoming part of history. So why don't we talk about it. I admire the old plantsmen who took the time to teach us the basics of this trade, and what a wonderful trade this is. If I compare the facilities and conditions they had to work with and under, then a salute is in order for them.

There is a great difference in the way they used to produce and the present methods. They were also more secretive about their work and the only exchange of information took place on Sunday morning either inside or outside the church. Location depended a lot on the type of sermon for that day.

Let's take the item — rhododendrons; making cuttings was unheard of, you had to graft them. That was done in the spring in cold frames under double glass. Sometimes with disastrous results, but there was no research or any other information available, and still they produced good saleable plants. A lot of


Author: Joerg Leiss

PP: 387

We have handled tree peonies for a long time, buying from Europe, then from Japan when our European sources dried up. Japanese suppliers we found to be not too reliable in supply—and naming especially—so we decided to propagate them ourselves.

Surveying the stock available to us, we felt that only the best would do. Up to this time we bought what the supplier offered, often inferior varieties. European varieties, while being developed from the same source, are quite distinct from Asiatic varieties in that they are usually fully-double, large-flowered, often so heavy that the stems cannot carry the bloom which then is hidden by foliage.

Asiatic varieties, in contrast, are of semidouble to double types with stiffer stems which carry the flowers well above the foliage. There are exceptions to both rules of course.

Tree peonies (Paeonia suffruticosa) are usually propagated by grafting on well-branched roots of P. lactiflora, the herbaceous peony. Grafting commences toward the end of August.


Author: Martin Van Hof

PP: 389

Some of us can remember back quite a few years—let us say 70–75 years. This, of course, cannot be called ancient but neither is it new, so let us call it old. I want to dwell a couple of minutes on propagation in Boskoop, Holland. I recall propagation by hardwood cuttings where wounding was used with a double long cut which gave a larger surface for callus which meant also a better chance for rooting. Wounding was and still is practiced in propagation by layering. Even evergreens, such as junipers, in a somewhat crude way were propagated by cuttings on the north side of a windbreak. The medium, generally dredged out of a canal, was mud; later it was mixed with peat moss. The cuttings were inserted by pushing them into that mixture with the finger so that below the soil the cutting was "V" shaped with the base of the cutting heading up. Softwoods were grown too but this required either frames with double sash or a greenhouse. At the age of 24 I came to these United States and worked

Author: Hans Hess

PP: 392

This is a very long title relating to what do you do with those grafts after you receive them in the hectic spring season. You have already said four or five times that you should never have ordered them after the poor experience of past years. Next year you will not take that extra drink or two and this won't happen, but the fact remains that here are these 500 or 1000 plants just delivered by United Parcel Service or Air Freight, and what are you going to do to improve last year's results.

Well, after a long trip you are usually tired and thirsty, so it is logical to feel that these plants are also tired and thirsty. Let's unpack them and see what they look like, and give them a drink of water; your preference of beverage might not give the results hoped for. Now that their thirst has been met let's put them in a shaded area protected from the wind for a day or two, so that they can become accustomed to normal light after having spent several days in nearly complete darkness. When you


Author: Leonard Savella

PP: 395

My talk today will be on top grafting Acer palmatum var. dissectum and Cornus florida ‘Welchiil’, although any of the Japanese maples or the tree form dogwoods can be grafted in the same manner if you so desire.

Top grafting of Acer palmatum var. dissectum and Cornus florida ‘Welchii’ to many propagators may not be something new; however, the methods we use to propagate these two particular plants may be an improvement over the old methods.

The preparation of understocks are the same for both maples and dogwoods. We start by selecting our understocks in the spring. This is not always an easy task because the supply of straight, strong stems may be short. The propagator then has to select the best he can from what is available.

For maples the understocks should be tall enough so that when they are decapitated and ready to graft, the stem will be at least 18" tall and have a caliper of 3/16 inches or more. In my experiences stems grafted at 18 inches and up to 3 feet have made the best


Author: Hoy C. Grigsby

PP: 398

Cuttings taken in December from 6-year-old Pinus taeda L. trees rooted 110 percent better when they were stored upright for 48 hours at 35° to 38° F, left intact, and treated with indolebutyric acid (IBA) than when they were oriented horizontally, reclipped at their bases, and treated with IBA without storage or chilling Mixed with Captan in talc, a 0.6 percent concentration of IBA produced more rooting than concentrations of 0.8 and 10 percent. N-dimethylaminosuccinamic acid (B-Nine) at 1,500 and 3,000 ppm in combination with IBA and Captan was detrimental to rooting.

Author: M. Leslie Hancock

PP: 403

My talk today concerns the addition of soil heating to the previously described Burlap Cloud method of summer cutting propagation. This method is not new, and has been presented twice at previous annual meetings of our Society. It has also been described in the book, Plant Propagation, by Mahlstede and Haber.

Briefly, it is an economical method of taking advantage of all natural agencies that promote plant growth and rooting, namely high humidity, filtered sunlight and abundant soil moisture. The chamber is a lightly constructed frame of 1-inch cedar boards, 3'9" × 12", to which is fastened along one side a length of 40 inch width of jute burlap, 10 oz. grade. During the hot part of the day, this burlap cover is stretched over finishing nails along the opposite side of the wooden frame or chamber. When in this position no dry outside air or direct sunlight can enter the chamber except through the moist burlap.

Preparation of soil. Soil for the cutting beds is rubbed through a ¾ or 1


Author: Thomas A. Fretz

PP: 405

A series of experiments on weed problems associated with container plant production are discussed. In weed competition studies both Amaranthus retroflexus L (pigweed) and Digitaria sanguinalis (L ) Scop. (crabgrass) at densities of 1, 2, 4, 8, 16 and 32 plants per 1 gallon nursery container significantly reduced the size of Ilex crenata Thunb ‘Convexa’ (Japanese holly) over the hand-weeded controls. Japanese holly plants were 30–75% reduced in size from the controls due to weed competition effects.

After 2 years of study the following herbicides, CIPC + PPG -124 at 8 lb ai / A, EPTC at 5 and 20 lb ai / A, CIPC at 8 lb ai / A, dichlobeml at 4 and 12 lb lb a i/A, and diphenamid at 20 lb ai / A when impregnated on milled pine bark mulch calculated to deliver the expressed rate when applied at a depth of ½ inch provided adequate control of both broadleaf and grass weed species for 150 days in container grown Rhododendron obtusum Planch var. amoenum Rehd ‘Hino Crimson’ (Hino Crimson azalea) and Japanese holly. Severe injury was observed on both container grown species from the use of dichlobenil at the 12 lb ai / A rate. EPTC at the 20 lb ai / A rate caused excessive injury to only the Hino Crimson azalea.

Studies conducted for 2 growing seasons showed that preemergent herbicide applications of the following materials, dichlobenil at 12 lb ai / A, trifluralin at 8 lb ai / A, EPTC at 5 and 20 lb ai / A, CIPC + PPG - 124 at 8 lb ai / A and diphenamid at 20 lb ai / A provided adequate broadleaf and grass weed control 163 days after application when employed on container-grown Rhododendron obtusum Planch var. amoenum Rehd. ‘Coral Bells’ (Coral Bells azalea) and Japanese holly EPTC at 20 lb ai / A caused excessive injury to the Coral Bells azalea, while dichlobenil at 12 lb ai / A severely injured both species.


Author: Harvey Gray

PP: 416

The production of containerized woody plants with the desired soil mixes is a major operation. If the plants to be marketed in containers could be grown in a medium in beds, properly spaced, much of the labor might be reduced. Plants grown in beds are easier to care for, particularly in regard to watering and fertilizing. The following remarks are made with these points in mind.

Experience and observation have proven that a soil mix high in organic matter and with a fair amount of clay has several points in its favor. Increased water holding capacity reduces the frequency of irrigation and a reduction of fertilizer loss. This is most important when containerized plants are on display for sale. A growing medium containing some soil classified as loam, possessing 20 to 25% clay, permits the roots of certain container-grown plants to make ready entry into the surrounding soil when planted in the landscape. Also the clay fraction of the loam soil serves in holding exchangeable ions


Author: W.A.G. Morsink

PP: 420

Trials on mist propagation of sugar maple have been in progress since 1968 in Toronto, Ontario, as part of the "Superior Shade Tree Programme for Ontario" (6). Procedures on vegetative propagation have recently been reviewed (1). Softwood cuttings (15 cm) of sugar maple collected in June have been rooted with varying success, using IBA and mist (2, 3, 4, 5, 8). Little information was available on the precise effect of auxins, length of cuttings, base diameter and a number of other questions. A number of small exploratory tests were carried out over the last 4 years to gain information on mist propagation of this species.

The rooting medium was a 2:1:1 (v / v / v) mixture of sandy loam top soil, vermiculite, and peatmoss, sterilized at 82° C.

Collection of cuttings. Juvenile softwood cuttings taken in the middle of June in Dorset, Ontario, rooted between 65% and 89%. At this time cuttings had fully elongated bottom leaves while the apical meristem was in full growth. Cuttings taken in


Author: Robert W. King

PP: 83

The very complex chemical mechanisms involved in plant development and growth can be summed up simply as follows:

Author: Richard W. Bosley

PP: 424

In the 25 years that I have been in the business of growing hybrid rhododendrons I have been exposed to many expert opinions both in person and through programs and publications—such as those of the Plant Propagators' Society. I have appreciated these ideas as they have been useful in expanding my knowledge and often enabling me to produce a better product. Two years ago I left the nursery I had been associated with for most of my life to start my own nursery which is called "Plant Systems". I would like to share some revelations I have had, regarding one hybrid rhododendron, ‘Nova Zembla’, during these 2 years and how these experiences compare with the myths to which I have been exposed.

I do not wish to imply in any way that the experiences that others have had were not valid because I am sure they were. I would also like to suggest that what worked for me may not work for another person or for another plant.

To give a little background regarding the crop environment, the plants were


Author: R.A. Fleming

PP: 428

Baycovin, more properly known in research as DEPC, or the diethyl ester of pyrocarbonic acid, has been used as a sterilizing agent for the preservation of fruit juices both fermented and nonfermented. It has shown anti-fungal properties when used as a post-harvest dip on strawberries (3), and is also toxic to a wide spectrum of microorganisms, including mycelial fungi which affect greenhouse crops.

A characteristic of the chemical is that it hydrolyzes readily to carbon dioxide and alcohol. The possibility of using the material as a sterilizing agent for greenhouse soils or plant propagation media seemed of interest and utility in view of its toxicity to fungi and the fact that its use would not give rise to residue problems as do other biocidal materials.

Baycovin or DEPC was first manufactured by Farbenfabriken Bayer A.G., Leverkusen, Germany. Its solubility in water is 0.6%, and in 96% ethyl alcohol 50% with hydrolysis. Baycovin is harmless to humans under most conditions of use


Author: Richard E. Cross

PP: 431

In the area where we have our nursery in Minnesota most conifer propagation is done during the winter months. If it were possible I would start in November and December, but because of pressures from tree and shrub digging and from Christmas business, it is usually about the first of the year before we get into greenhouse propagation.

Quite a few years ago, when I was new at making cuttings and grafts I read all the material I could find on the subject of propagation. I was under the impression I should take cuttings and scions and use them in a very short time, certainly within several days. This would be fine if we were in a mild climate where we would be able to go to the field and take fresh propagation materials daily.

About 6 years ago I began to wonder about the difficulty we were encountering in gathering cuttings and scions in January, February and March to get fresh material for our use. Also some winters there was winter damage to the cuttings, showing up after these later


Author: Richard H. Zimmerman

PP: 434

Seedlings of pears and apples, in common with those of many other tree species, have a juvenile phase lasting 4–5 years or more. This long period before the seedlings flower is a major hindrance to rapid progress in tree breeding programs, which require several seedling generations for success. This is especially true for the U.S. Department of Agriculture program to develop high quality pears resistant to fire blight. In order to develop methods for shortening the juvenile phase in pears, it became clear that we needed to understand better the nature of juvenility and its relationship to flower initiation. From a review of the literature, it also seemed clear that such research must be done with seedling trees since vegetatively propagated trees do not always respond to treatments in the same way as seedlings.

Pear seedlings are difficult to use in juvenility studies because of their genetic variability and because they are rather difficult to keep in active growth in the greenhouse


Author: W.G. Ronald, W.A. Cumming

PP: 437

Hardwood or softwood cuttings of most poplars root easily with the exception of white poplars and aspens which belong to one section of the genus Populus. White poplars generally propagate easily by softwood cuttings and with more difficulty by hardwood cuttings; both softwood and hardwood aspen cuttings generally root poorly. Under natural conditions the aspens regenerate quickly from root suckers and seed.

Columnar European aspen (Populus tremula L. ‘Erecta’) is a valuable columnar clone that has proven difficult to propagate. Many attempts, by the authors, to root softwood cuttings have resulted in less than 10% success. Despite its value as a hardy upright poplar for northern areas, propagation failures have prevented wide commercial acceptance of this clone.

Propagation failures have stimulated research into aspen clonal propagation by greenwood cuttings (1), adventitious etiolated cuttings from root cuttings (1, 3) and tissue culture (5, 6). While these techniques have been


Author: Chiko Haramaki

PP: 442

Gloxinia, Sinningia speciosa, does not come true when propagated by seed and new plants of a given cultivar are primarily obtained by leaf cuttings and occasionally by stem cuttings. This research was undertaken to see if gloxinia could be propagated by tissue culture and if so, would it be possible to rapidly multiply it under controlled conditions. During the last few years a number of herbaceous plants have been propagated by tissue culture, such as asparagus (13), carnation (1, 4), cattleya (11), chrysanthemum (5, 6), cymbidium (7, 12), dahlia (8), iris (2), potato (9), rhubarb (14), and strawberry (3).

This study was done in cooperation with Dr. Toshio Murashige who graciously invited me to work in his well-equipped, tissue-culture laboratories at the University of California, Riverside.

In the preparation of the plant the shoots were cut back to the tuber when it was found that all of these shoots were reproductive. The ideal stage for taking vegetative shoots was when the new


Author: Ralph Shugert

PP: 450

When I first started thinking about this very important topic, I was almost certain that there would be very, very few references in past volumes of our Proceedings. My, how mistaken I was! At the Eighth Meeting of our beloved Society, Henry Weller (5) told us that being aware of the cost of production, and doing something about it, is just as important to the nurseryman as the "know-how" of propagation. Then in 1962 in Cincinnati, Ohio, George Oki (1) traveled from Sacramento, California to share with us the importance of daily, weekly, monthly and annual records. When you review this outstanding paper, you can see appended to the paper the various forms that George uses at his outstanding nursery. Apparently there were some members stimulated by this report because the following year, in my hometown of St. Louis, Missouri, there was a round table discussion entitled "Cost Control in Propagation" (3). The recorder of this discussion, Wayne Lovelace (a former co-worker of mine), tells of

Author: Donald R. Egolf

PP: 456

The U. S. National Arboretum, Washington, D.C., has become a major center for the development, evaluation, and distribution of woody ornamental cultivars. A new cultivar may arise as a selection from a seedling population derived from introduced seed, a naturally occurring or induced mutant, or a hybrid resultant from controlled pollination. The early hybridization work of B. Y. Morrison, who produced the vast array of Glenn Dale azaleas (18); and of 0. M. Freeman, who produced Magnolia × ‘Freeman’ and lsquo;Maryland’ (11, 17), has been expanded in the last 15 years to encompass a major shrub breeding project and more recently a tree breeding project. From these research programs some 40 cultivars; have been introduced and numerous seedling selections made which will yield superior shrub and tree cultivars in the future.

The development of a new cultivar by hybridization requires not only a minimum of 8–10 years for a shrub and many more years for a tree, but also a great expenditure of funds.


Author: Alfred J. Fordham

PP: 470

When reproduced from seeds, both in nature and in cultivation, some conifers give rise to many seedlings which are quite unlike the parent plants. These variants, which originate as mutations, generally retain their characteristics when propagated vegetatively. Canadian hemlock (Tsuga canadensis) is an excellent example of a conifer which produces seedlings that vary widely in genetic make-up.

Some idea of the extent of variation in Canadian hemlock is brought out by the fact that through the years the Arnold Arboretum has received plants or propagating material of 280 clones. They were discovered in the woods or in nursery rows by contributors who considered them worthy of perpetuation at a botanical institution. A search of the Arboretum's records reveals that hemlock variants were being received in the infancy of this century-old organization. Some were named and others, as is the case with many received more recently, simply bore descriptive notations such as, "dense form","dense


Author: J.C. McDaniel

PP: 477

Celtis laevigata. When I lived at Nashville, Tennessee I decided that the commonest deciduous tree there, at least in the older parts of town, was probably the Sugarberry or Mississippi Hackberry, Celtis laevigata. Though the common eastern hackberry, C. occidentalis, also occurred there, the southern species probably outnumbered it 100 to 1. It is also common, I see, on streets and woods borders here in eastern Virginia and many other parts of the South, as far as southern Florida and southwestward at least to Monterrey, Mexico. In the Mississippi and Missouri Valleys, it grows wild as far north as Hannibal, Missouri and Quincy, Illinois. Botanical manuals, such as Rydberg's "Flora of the Prairies and Plains of Central North America" list it for southeast Kansas.

C. laevigata is prevalent in the southern third of Illinois, though not native around Urbana. There at the upper edge of Zone 6a, C. laevigata trees from at least two sources have proved hardy over a period of 15 years, and


Author: Richard E. Puffer

PP: 87

Monterey pine (Pinus radiata) is used to a considerable extent in landscaping and for Christmas tree farms in Southern California.

One of the biggest problems has been the effect of air pollution on the trees. Monterey pine trees vary considerably in their susceptibility to air pollution, ranging all the way from no damage to, in a few cases, death of the tree. Most of the susceptible trees show a yellow mottling of the needles and, occasionally, will turn brown immediately after a heavy attack. This problem led to the study of the rooting of cuttings from resistant trees to see if clones could be developed that would be resistant to air pollution. As we studied the variability among Monterey pine seedlings, we discovered that an occasional tree would grow into an almost perfect Christmas tree shape with very little pruning. Some of these trees also had desirable color and needle characteristics that made them very desirable for Christmas trees. We visited farms that had planted


Author: William Snyder

PP: 479

The question box session convened at 8:00 p.m. in the West Ballroom. Dr. Bill Snyder served as moderator.

MODERATOR SNYDER: We have several questions here, and though we seem to be few in number this evening what we lack in quantity we will make up for in quality. Many of these questions are directed to specific individuals and if they are not present, we will set them aside in the event that they may come in later in the meeting. The first question is for Bill Morsink. Did you sterilize the cuttings of Acersaccharum?

BILL MORSINK: We sterilized the soil in which they are stuck at 180° F and this is very important. If we do not sterilize the soil we get only about 20% rooting, whereas with sterilized soils using the right size cuttings we can get up to 90% rooting.

MODERATOR SNYDER: Do you treat the cuttings in any way with a fungicide?

BILL MORSINK: I tried a few of these materials, but I found that the sugar maple is extremely sensitive to many of these


Author: Tokuji Furuta

PP: 94

The room was gleaming white and seemingly sterile. Occasionally a door opened and music from a transistor radio entered from somewhere outside. Otherwise, there was an air of hushed expectation.

The only sound was a gentle hiss as air passed through the adjustable louvers into the room, combined with a faint hum from the lights. This was all the sound that could be heard as women robed in white moved about silently inspecting the rows and rows of white plastic trays. From time to time they would stop to more closely inspect and manipulate one of the living creatures on the white trays.

The room was divided into two parts by a lightproof curtain. Half of the room was brilliantly lit from overhead lights. On the basis of the glow from each lamp one determines that at least two types were used. The other half of the room was dimly lit for part of the time, in darkness the remainder. Every 12 hours, the curtains automatically parted and the lights moved to the dark side.


Author: Eugene Baciu

PP: 103

Seeds of short life have presented problems for the nurseryman for centuries. In the days of the sailing ships, expeditions were made to gather plants from all over the world. Many of these plants had to be grown in containers on the ships and, in most instances, it took years to transport these plants to Europe and other countries. The steamship helped tremendously in transporting the plants that bear short-lived seeds. Then came the airplane and now we have jets that can transport the seeds from any place in the world to the grower in a few hours. Of course, at times it has taken up to six weeks to get them out of Customs. I have had seed received from Thailand by Customs on August 2 which were not released until September 16, resulting in very poor germination. I was unable to get a reason from Customs for their refusal to release my shipment. Perhaps some work could be done with Customs to shorten this period of time.

Resulting from our changing habits of living, we have developed